WSL2-Linux-Kernel/kernel/trace/trace_kprobe.c

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// SPDX-License-Identifier: GPL-2.0
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/*
* Kprobes-based tracing events
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
*
* Created by Masami Hiramatsu <mhiramat@redhat.com>
*
*/
#define pr_fmt(fmt) "trace_kprobe: " fmt
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
#include <linux/security.h>
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/rculist.h>
#include <linux/error-injection.h>
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
#include "trace_dynevent.h"
#include "trace_kprobe_selftest.h"
#include "trace_probe.h"
#include "trace_probe_tmpl.h"
#define KPROBE_EVENT_SYSTEM "kprobes"
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
#define KRETPROBE_MAXACTIVE_MAX 4096
/* Kprobe early definition from command line */
static char kprobe_boot_events_buf[COMMAND_LINE_SIZE] __initdata;
tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline When having kprobe trace event start up tests enabled and adding a kprobe_event on the kernel command line, it produced the following: trace_kprobe: Testing kprobe tracing: WARNING: CPU: 5 PID: 1 at kernel/trace/trace_kprobe.c:1724 kprobe_trace_self_tests_init+0x32d/0x36b Modules linked in: CPU: 5 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc1-test+ #249 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:kprobe_trace_self_tests_init+0x32d/0x36b Code: b7 e8 4f 8d a2 fe 85 c0 74 10 0f 0b 48 c7 c7 c8 1b 0d b7 ff c3 e8 19 af 99 fe 48 c7 c7 40 93 27 b7 e8 7f 1a a5 fe 85 c0 74 10 <0f> 0b 48 c7 c7 f8 1b 0d b7 ff c3 e8 f9 ae 9 a0 fe 85 RSP: 0018:ffffb36e40653e08 EFLAGS: 00010286 RAX: 00000000fffffff0 RBX: 0000000000000000 RCX: ffffb36e40653d5c RDX: 0000000000000000 RSI: ffffffffb72776e0 RDI: 0000000000000246 RBP: ffff98414fe58ff8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff98415d8aa940 R12: 0000000000000000 R13: ffffffffb737c1b0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff98415ea80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f959ce741b8 CR3: 000000011a210002 CR4: 00000000001606e0 Call Trace: ? init_kprobe_trace+0x19e/0x19e ? do_early_param+0x8e/0x8e do_one_initcall+0x6f/0x2b4 ? do_early_param+0x8e/0x8e kernel_init_freeable+0x21d/0x2c6 ? rest_init+0x146/0x146 kernel_init+0xa/0x10a ret_from_fork+0x3a/0x50 ---[ end trace 488430c083a4c956 ]--- As with the trace events, if a trace event is set on the kernel command line, the trace events start up tests are suspended. The kprobe start up tests should do the same when a kprobe is enabled on the kernel command line. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-24 02:50:34 +03:00
static bool kprobe_boot_events_enabled __initdata;
static int __init set_kprobe_boot_events(char *str)
{
strlcpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE);
return 0;
}
__setup("kprobe_event=", set_kprobe_boot_events);
static int trace_kprobe_create(int argc, const char **argv);
static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev);
static int trace_kprobe_release(struct dyn_event *ev);
static bool trace_kprobe_is_busy(struct dyn_event *ev);
static bool trace_kprobe_match(const char *system, const char *event,
int argc, const char **argv, struct dyn_event *ev);
static struct dyn_event_operations trace_kprobe_ops = {
.create = trace_kprobe_create,
.show = trace_kprobe_show,
.is_busy = trace_kprobe_is_busy,
.free = trace_kprobe_release,
.match = trace_kprobe_match,
};
/*
* Kprobe event core functions
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
*/
struct trace_kprobe {
struct dyn_event devent;
struct kretprobe rp; /* Use rp.kp for kprobe use */
kprobes: Optimize hot path by using percpu counter to collect 'nhit' statistics When doing ebpf+kprobe on some hot TCP functions (e.g. tcp_rcv_established), the kprobe_dispatcher() function shows up in 'perf report'. In kprobe_dispatcher(), there is a lot of cache bouncing on 'tk->nhit++'. 'tk->nhit' and 'tk->tp.flags' also share the same cacheline. perf report (cycles:pp): 8.30% ipv4_dst_check 4.74% copy_user_enhanced_fast_string 3.93% dst_release 2.80% tcp_v4_rcv 2.31% queued_spin_lock_slowpath 2.30% _raw_spin_lock 1.88% mlx4_en_process_rx_cq 1.84% eth_get_headlen 1.81% ip_rcv_finish ~~~~ 1.71% kprobe_dispatcher ~~~~ 1.55% mlx4_en_xmit 1.09% __probe_kernel_read perf report after patch: 9.15% ipv4_dst_check 5.00% copy_user_enhanced_fast_string 4.12% dst_release 2.96% tcp_v4_rcv 2.50% _raw_spin_lock 2.39% queued_spin_lock_slowpath 2.11% eth_get_headlen 2.03% mlx4_en_process_rx_cq 1.69% mlx4_en_xmit 1.19% ip_rcv_finish 1.12% __probe_kernel_read 1.02% ehci_hcd_cleanup Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Kernel Team <kernel-team@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1454531308-2441898-1-git-send-email-kafai@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 23:28:28 +03:00
unsigned long __percpu *nhit;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
const char *symbol; /* symbol name */
struct trace_probe tp;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
};
static bool is_trace_kprobe(struct dyn_event *ev)
{
return ev->ops == &trace_kprobe_ops;
}
static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev)
{
return container_of(ev, struct trace_kprobe, devent);
}
/**
* for_each_trace_kprobe - iterate over the trace_kprobe list
* @pos: the struct trace_kprobe * for each entry
* @dpos: the struct dyn_event * to use as a loop cursor
*/
#define for_each_trace_kprobe(pos, dpos) \
for_each_dyn_event(dpos) \
if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos)))
#define SIZEOF_TRACE_KPROBE(n) \
(offsetof(struct trace_kprobe, tp.args) + \
(sizeof(struct probe_arg) * (n)))
static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
return tk->rp.handler != NULL;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static nokprobe_inline const char *trace_kprobe_symbol(struct trace_kprobe *tk)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
return tk->symbol ? tk->symbol : "unknown";
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static nokprobe_inline unsigned long trace_kprobe_offset(struct trace_kprobe *tk)
{
return tk->rp.kp.offset;
}
static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk)
{
return !!(kprobe_gone(&tk->rp.kp));
}
static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk,
struct module *mod)
{
int len = strlen(module_name(mod));
const char *name = trace_kprobe_symbol(tk);
return strncmp(module_name(mod), name, len) == 0 && name[len] == ':';
}
static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk)
{
char *p;
bool ret;
if (!tk->symbol)
return false;
p = strchr(tk->symbol, ':');
if (!p)
return true;
*p = '\0';
mutex_lock(&module_mutex);
ret = !!find_module(tk->symbol);
mutex_unlock(&module_mutex);
*p = ':';
return ret;
}
static bool trace_kprobe_is_busy(struct dyn_event *ev)
{
struct trace_kprobe *tk = to_trace_kprobe(ev);
return trace_probe_is_enabled(&tk->tp);
}
static bool trace_kprobe_match_command_head(struct trace_kprobe *tk,
int argc, const char **argv)
{
char buf[MAX_ARGSTR_LEN + 1];
if (!argc)
return true;
if (!tk->symbol)
snprintf(buf, sizeof(buf), "0x%p", tk->rp.kp.addr);
else if (tk->rp.kp.offset)
snprintf(buf, sizeof(buf), "%s+%u",
trace_kprobe_symbol(tk), tk->rp.kp.offset);
else
snprintf(buf, sizeof(buf), "%s", trace_kprobe_symbol(tk));
if (strcmp(buf, argv[0]))
return false;
argc--; argv++;
return trace_probe_match_command_args(&tk->tp, argc, argv);
}
static bool trace_kprobe_match(const char *system, const char *event,
int argc, const char **argv, struct dyn_event *ev)
{
struct trace_kprobe *tk = to_trace_kprobe(ev);
return strcmp(trace_probe_name(&tk->tp), event) == 0 &&
(!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) &&
trace_kprobe_match_command_head(tk, argc, argv);
}
static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
{
unsigned long nhit = 0;
int cpu;
for_each_possible_cpu(cpu)
nhit += *per_cpu_ptr(tk->nhit, cpu);
return nhit;
}
static nokprobe_inline bool trace_kprobe_is_registered(struct trace_kprobe *tk)
{
return !(list_empty(&tk->rp.kp.list) &&
hlist_unhashed(&tk->rp.kp.hlist));
}
/* Return 0 if it fails to find the symbol address */
static nokprobe_inline
unsigned long trace_kprobe_address(struct trace_kprobe *tk)
{
unsigned long addr;
if (tk->symbol) {
addr = (unsigned long)
kallsyms_lookup_name(trace_kprobe_symbol(tk));
if (addr)
addr += tk->rp.kp.offset;
} else {
addr = (unsigned long)tk->rp.kp.addr;
}
return addr;
}
static nokprobe_inline struct trace_kprobe *
trace_kprobe_primary_from_call(struct trace_event_call *call)
{
struct trace_probe *tp;
tp = trace_probe_primary_from_call(call);
if (WARN_ON_ONCE(!tp))
return NULL;
return container_of(tp, struct trace_kprobe, tp);
}
bool trace_kprobe_on_func_entry(struct trace_event_call *call)
{
struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
return tk ? kprobe_on_func_entry(tk->rp.kp.addr,
tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name,
tk->rp.kp.addr ? 0 : tk->rp.kp.offset) : false;
}
bool trace_kprobe_error_injectable(struct trace_event_call *call)
{
struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
return tk ? within_error_injection_list(trace_kprobe_address(tk)) :
false;
}
static int register_kprobe_event(struct trace_kprobe *tk);
static int unregister_kprobe_event(struct trace_kprobe *tk);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
static int kretprobe_dispatcher(struct kretprobe_instance *ri,
struct pt_regs *regs);
static void free_trace_kprobe(struct trace_kprobe *tk)
{
if (tk) {
trace_probe_cleanup(&tk->tp);
kfree(tk->symbol);
free_percpu(tk->nhit);
kfree(tk);
}
}
/*
* Allocate new trace_probe and initialize it (including kprobes).
*/
static struct trace_kprobe *alloc_trace_kprobe(const char *group,
const char *event,
void *addr,
const char *symbol,
unsigned long offs,
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
int maxactive,
int nargs, bool is_return)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct trace_kprobe *tk;
int ret = -ENOMEM;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL);
if (!tk)
return ERR_PTR(ret);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
kprobes: Optimize hot path by using percpu counter to collect 'nhit' statistics When doing ebpf+kprobe on some hot TCP functions (e.g. tcp_rcv_established), the kprobe_dispatcher() function shows up in 'perf report'. In kprobe_dispatcher(), there is a lot of cache bouncing on 'tk->nhit++'. 'tk->nhit' and 'tk->tp.flags' also share the same cacheline. perf report (cycles:pp): 8.30% ipv4_dst_check 4.74% copy_user_enhanced_fast_string 3.93% dst_release 2.80% tcp_v4_rcv 2.31% queued_spin_lock_slowpath 2.30% _raw_spin_lock 1.88% mlx4_en_process_rx_cq 1.84% eth_get_headlen 1.81% ip_rcv_finish ~~~~ 1.71% kprobe_dispatcher ~~~~ 1.55% mlx4_en_xmit 1.09% __probe_kernel_read perf report after patch: 9.15% ipv4_dst_check 5.00% copy_user_enhanced_fast_string 4.12% dst_release 2.96% tcp_v4_rcv 2.50% _raw_spin_lock 2.39% queued_spin_lock_slowpath 2.11% eth_get_headlen 2.03% mlx4_en_process_rx_cq 1.69% mlx4_en_xmit 1.19% ip_rcv_finish 1.12% __probe_kernel_read 1.02% ehci_hcd_cleanup Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Kernel Team <kernel-team@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1454531308-2441898-1-git-send-email-kafai@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 23:28:28 +03:00
tk->nhit = alloc_percpu(unsigned long);
if (!tk->nhit)
goto error;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (symbol) {
tk->symbol = kstrdup(symbol, GFP_KERNEL);
if (!tk->symbol)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
goto error;
tk->rp.kp.symbol_name = tk->symbol;
tk->rp.kp.offset = offs;
} else
tk->rp.kp.addr = addr;
if (is_return)
tk->rp.handler = kretprobe_dispatcher;
else
tk->rp.kp.pre_handler = kprobe_dispatcher;
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
tk->rp.maxactive = maxactive;
INIT_HLIST_NODE(&tk->rp.kp.hlist);
INIT_LIST_HEAD(&tk->rp.kp.list);
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
ret = trace_probe_init(&tk->tp, event, group, false);
if (ret < 0)
goto error;
dyn_event_init(&tk->devent, &trace_kprobe_ops);
return tk;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
error:
free_trace_kprobe(tk);
return ERR_PTR(ret);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static struct trace_kprobe *find_trace_kprobe(const char *event,
const char *group)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct dyn_event *pos;
struct trace_kprobe *tk;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
for_each_trace_kprobe(tk, pos)
if (strcmp(trace_probe_name(&tk->tp), event) == 0 &&
strcmp(trace_probe_group_name(&tk->tp), group) == 0)
return tk;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
return NULL;
}
static inline int __enable_trace_kprobe(struct trace_kprobe *tk)
{
int ret = 0;
if (trace_kprobe_is_registered(tk) && !trace_kprobe_has_gone(tk)) {
if (trace_kprobe_is_return(tk))
ret = enable_kretprobe(&tk->rp);
else
ret = enable_kprobe(&tk->rp.kp);
}
return ret;
}
static void __disable_trace_kprobe(struct trace_probe *tp)
{
struct trace_probe *pos;
struct trace_kprobe *tk;
list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
tk = container_of(pos, struct trace_kprobe, tp);
if (!trace_kprobe_is_registered(tk))
continue;
if (trace_kprobe_is_return(tk))
disable_kretprobe(&tk->rp);
else
disable_kprobe(&tk->rp.kp);
}
}
/*
* Enable trace_probe
* if the file is NULL, enable "perf" handler, or enable "trace" handler.
*/
static int enable_trace_kprobe(struct trace_event_call *call,
struct trace_event_file *file)
{
struct trace_probe *pos, *tp;
struct trace_kprobe *tk;
bool enabled;
int ret = 0;
tp = trace_probe_primary_from_call(call);
if (WARN_ON_ONCE(!tp))
return -ENODEV;
enabled = trace_probe_is_enabled(tp);
/* This also changes "enabled" state */
if (file) {
ret = trace_probe_add_file(tp, file);
if (ret)
return ret;
} else
trace_probe_set_flag(tp, TP_FLAG_PROFILE);
if (enabled)
return 0;
list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
tk = container_of(pos, struct trace_kprobe, tp);
if (trace_kprobe_has_gone(tk))
continue;
ret = __enable_trace_kprobe(tk);
if (ret)
break;
enabled = true;
}
if (ret) {
/* Failed to enable one of them. Roll back all */
if (enabled)
__disable_trace_kprobe(tp);
if (file)
trace_probe_remove_file(tp, file);
else
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
}
return ret;
}
/*
* Disable trace_probe
* if the file is NULL, disable "perf" handler, or disable "trace" handler.
*/
static int disable_trace_kprobe(struct trace_event_call *call,
struct trace_event_file *file)
{
struct trace_probe *tp;
tp = trace_probe_primary_from_call(call);
if (WARN_ON_ONCE(!tp))
return -ENODEV;
if (file) {
if (!trace_probe_get_file_link(tp, file))
return -ENOENT;
if (!trace_probe_has_single_file(tp))
goto out;
trace_probe_clear_flag(tp, TP_FLAG_TRACE);
} else
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
if (!trace_probe_is_enabled(tp))
__disable_trace_kprobe(tp);
out:
if (file)
/*
* Synchronization is done in below function. For perf event,
* file == NULL and perf_trace_event_unreg() calls
* tracepoint_synchronize_unregister() to ensure synchronize
* event. We don't need to care about it.
*/
trace_probe_remove_file(tp, file);
return 0;
}
#if defined(CONFIG_KPROBES_ON_FTRACE) && \
!defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE)
static bool __within_notrace_func(unsigned long addr)
{
unsigned long offset, size;
if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset))
return false;
/* Get the entry address of the target function */
addr -= offset;
/*
* Since ftrace_location_range() does inclusive range check, we need
* to subtract 1 byte from the end address.
*/
return !ftrace_location_range(addr, addr + size - 1);
}
static bool within_notrace_func(struct trace_kprobe *tk)
{
unsigned long addr = trace_kprobe_address(tk);
char symname[KSYM_NAME_LEN], *p;
if (!__within_notrace_func(addr))
return false;
/* Check if the address is on a suffixed-symbol */
if (!lookup_symbol_name(addr, symname)) {
p = strchr(symname, '.');
if (!p)
return true;
*p = '\0';
addr = (unsigned long)kprobe_lookup_name(symname, 0);
if (addr)
return __within_notrace_func(addr);
}
return true;
}
#else
#define within_notrace_func(tk) (false)
#endif
/* Internal register function - just handle k*probes and flags */
static int __register_trace_kprobe(struct trace_kprobe *tk)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
int i, ret;
ret = security_locked_down(LOCKDOWN_KPROBES);
if (ret)
return ret;
if (trace_kprobe_is_registered(tk))
return -EINVAL;
if (within_notrace_func(tk)) {
pr_warn("Could not probe notrace function %s\n",
trace_kprobe_symbol(tk));
return -EINVAL;
}
for (i = 0; i < tk->tp.nr_args; i++) {
ret = traceprobe_update_arg(&tk->tp.args[i]);
if (ret)
return ret;
}
/* Set/clear disabled flag according to tp->flag */
if (trace_probe_is_enabled(&tk->tp))
tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED;
else
tk->rp.kp.flags |= KPROBE_FLAG_DISABLED;
if (trace_kprobe_is_return(tk))
ret = register_kretprobe(&tk->rp);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
else
ret = register_kprobe(&tk->rp.kp);
return ret;
}
/* Internal unregister function - just handle k*probes and flags */
static void __unregister_trace_kprobe(struct trace_kprobe *tk)
{
if (trace_kprobe_is_registered(tk)) {
if (trace_kprobe_is_return(tk))
unregister_kretprobe(&tk->rp);
else
unregister_kprobe(&tk->rp.kp);
/* Cleanup kprobe for reuse and mark it unregistered */
INIT_HLIST_NODE(&tk->rp.kp.hlist);
INIT_LIST_HEAD(&tk->rp.kp.list);
if (tk->rp.kp.symbol_name)
tk->rp.kp.addr = NULL;
}
}
/* Unregister a trace_probe and probe_event */
static int unregister_trace_kprobe(struct trace_kprobe *tk)
{
/* If other probes are on the event, just unregister kprobe */
if (trace_probe_has_sibling(&tk->tp))
goto unreg;
/* Enabled event can not be unregistered */
if (trace_probe_is_enabled(&tk->tp))
return -EBUSY;
tracing/kprobes: Fail to unregister if probe event files are in use When a probe is being removed, it cleans up the event files that correspond to the probe. But there is a race between writing to one of these files and deleting the probe. This is especially true for the "enable" file. CPU 0 CPU 1 ----- ----- fd = open("enable",O_WRONLY); probes_open() release_all_trace_probes() unregister_trace_probe() if (trace_probe_is_enabled(tp)) return -EBUSY write(fd, "1", 1) __ftrace_set_clr_event() call->class->reg() (kprobe_register) enable_trace_probe(tp) __unregister_trace_probe(tp); list_del(&tp->list) unregister_probe_event(tp) <-- fails! free_trace_probe(tp) write(fd, "0", 1) __ftrace_set_clr_event() call->class->unreg (kprobe_register) disable_trace_probe(tp) <-- BOOM! A test program was written that used two threads to simulate the above scenario adding a nanosleep() interval to change the timings and after several thousand runs, it was able to trigger this bug and crash: BUG: unable to handle kernel paging request at 00000005000000f9 IP: [<ffffffff810dee70>] probes_open+0x3b/0xa7 PGD 7808a067 PUD 0 Oops: 0000 [#1] PREEMPT SMP Dumping ftrace buffer: --------------------------------- Modules linked in: ipt_MASQUERADE sunrpc ip6t_REJECT nf_conntrack_ipv6 CPU: 1 PID: 2070 Comm: test-kprobe-rem Not tainted 3.11.0-rc3-test+ #47 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007 task: ffff880077756440 ti: ffff880076e52000 task.ti: ffff880076e52000 RIP: 0010:[<ffffffff810dee70>] [<ffffffff810dee70>] probes_open+0x3b/0xa7 RSP: 0018:ffff880076e53c38 EFLAGS: 00010203 RAX: 0000000500000001 RBX: ffff88007844f440 RCX: 0000000000000003 RDX: 0000000000000003 RSI: 0000000000000003 RDI: ffff880076e52000 RBP: ffff880076e53c58 R08: ffff880076e53bd8 R09: 0000000000000000 R10: ffff880077756440 R11: 0000000000000006 R12: ffffffff810dee35 R13: ffff880079250418 R14: 0000000000000000 R15: ffff88007844f450 FS: 00007f87a276f700(0000) GS:ffff88007d480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00000005000000f9 CR3: 0000000077262000 CR4: 00000000000007e0 Stack: ffff880076e53c58 ffffffff81219ea0 ffff88007844f440 ffffffff810dee35 ffff880076e53ca8 ffffffff81130f78 ffff8800772986c0 ffff8800796f93a0 ffffffff81d1b5d8 ffff880076e53e04 0000000000000000 ffff88007844f440 Call Trace: [<ffffffff81219ea0>] ? security_file_open+0x2c/0x30 [<ffffffff810dee35>] ? unregister_trace_probe+0x4b/0x4b [<ffffffff81130f78>] do_dentry_open+0x162/0x226 [<ffffffff81131186>] finish_open+0x46/0x54 [<ffffffff8113f30b>] do_last+0x7f6/0x996 [<ffffffff8113cc6f>] ? inode_permission+0x42/0x44 [<ffffffff8113f6dd>] path_openat+0x232/0x496 [<ffffffff8113fc30>] do_filp_open+0x3a/0x8a [<ffffffff8114ab32>] ? __alloc_fd+0x168/0x17a [<ffffffff81131f4e>] do_sys_open+0x70/0x102 [<ffffffff8108f06e>] ? trace_hardirqs_on_caller+0x160/0x197 [<ffffffff81131ffe>] SyS_open+0x1e/0x20 [<ffffffff81522742>] system_call_fastpath+0x16/0x1b Code: e5 41 54 53 48 89 f3 48 83 ec 10 48 23 56 78 48 39 c2 75 6c 31 f6 48 c7 RIP [<ffffffff810dee70>] probes_open+0x3b/0xa7 RSP <ffff880076e53c38> CR2: 00000005000000f9 ---[ end trace 35f17d68fc569897 ]--- The unregister_trace_probe() must be done first, and if it fails it must fail the removal of the kprobe. Several changes have already been made by Oleg Nesterov and Masami Hiramatsu to allow moving the unregister_probe_event() before the removal of the probe and exit the function if it fails. This prevents the tp structure from being used after it is freed. Link: http://lkml.kernel.org/r/20130704034038.819592356@goodmis.org Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-07-04 07:33:50 +04:00
/* Will fail if probe is being used by ftrace or perf */
if (unregister_kprobe_event(tk))
tracing/kprobes: Fail to unregister if probe event files are in use When a probe is being removed, it cleans up the event files that correspond to the probe. But there is a race between writing to one of these files and deleting the probe. This is especially true for the "enable" file. CPU 0 CPU 1 ----- ----- fd = open("enable",O_WRONLY); probes_open() release_all_trace_probes() unregister_trace_probe() if (trace_probe_is_enabled(tp)) return -EBUSY write(fd, "1", 1) __ftrace_set_clr_event() call->class->reg() (kprobe_register) enable_trace_probe(tp) __unregister_trace_probe(tp); list_del(&tp->list) unregister_probe_event(tp) <-- fails! free_trace_probe(tp) write(fd, "0", 1) __ftrace_set_clr_event() call->class->unreg (kprobe_register) disable_trace_probe(tp) <-- BOOM! A test program was written that used two threads to simulate the above scenario adding a nanosleep() interval to change the timings and after several thousand runs, it was able to trigger this bug and crash: BUG: unable to handle kernel paging request at 00000005000000f9 IP: [<ffffffff810dee70>] probes_open+0x3b/0xa7 PGD 7808a067 PUD 0 Oops: 0000 [#1] PREEMPT SMP Dumping ftrace buffer: --------------------------------- Modules linked in: ipt_MASQUERADE sunrpc ip6t_REJECT nf_conntrack_ipv6 CPU: 1 PID: 2070 Comm: test-kprobe-rem Not tainted 3.11.0-rc3-test+ #47 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007 task: ffff880077756440 ti: ffff880076e52000 task.ti: ffff880076e52000 RIP: 0010:[<ffffffff810dee70>] [<ffffffff810dee70>] probes_open+0x3b/0xa7 RSP: 0018:ffff880076e53c38 EFLAGS: 00010203 RAX: 0000000500000001 RBX: ffff88007844f440 RCX: 0000000000000003 RDX: 0000000000000003 RSI: 0000000000000003 RDI: ffff880076e52000 RBP: ffff880076e53c58 R08: ffff880076e53bd8 R09: 0000000000000000 R10: ffff880077756440 R11: 0000000000000006 R12: ffffffff810dee35 R13: ffff880079250418 R14: 0000000000000000 R15: ffff88007844f450 FS: 00007f87a276f700(0000) GS:ffff88007d480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00000005000000f9 CR3: 0000000077262000 CR4: 00000000000007e0 Stack: ffff880076e53c58 ffffffff81219ea0 ffff88007844f440 ffffffff810dee35 ffff880076e53ca8 ffffffff81130f78 ffff8800772986c0 ffff8800796f93a0 ffffffff81d1b5d8 ffff880076e53e04 0000000000000000 ffff88007844f440 Call Trace: [<ffffffff81219ea0>] ? security_file_open+0x2c/0x30 [<ffffffff810dee35>] ? unregister_trace_probe+0x4b/0x4b [<ffffffff81130f78>] do_dentry_open+0x162/0x226 [<ffffffff81131186>] finish_open+0x46/0x54 [<ffffffff8113f30b>] do_last+0x7f6/0x996 [<ffffffff8113cc6f>] ? inode_permission+0x42/0x44 [<ffffffff8113f6dd>] path_openat+0x232/0x496 [<ffffffff8113fc30>] do_filp_open+0x3a/0x8a [<ffffffff8114ab32>] ? __alloc_fd+0x168/0x17a [<ffffffff81131f4e>] do_sys_open+0x70/0x102 [<ffffffff8108f06e>] ? trace_hardirqs_on_caller+0x160/0x197 [<ffffffff81131ffe>] SyS_open+0x1e/0x20 [<ffffffff81522742>] system_call_fastpath+0x16/0x1b Code: e5 41 54 53 48 89 f3 48 83 ec 10 48 23 56 78 48 39 c2 75 6c 31 f6 48 c7 RIP [<ffffffff810dee70>] probes_open+0x3b/0xa7 RSP <ffff880076e53c38> CR2: 00000005000000f9 ---[ end trace 35f17d68fc569897 ]--- The unregister_trace_probe() must be done first, and if it fails it must fail the removal of the kprobe. Several changes have already been made by Oleg Nesterov and Masami Hiramatsu to allow moving the unregister_probe_event() before the removal of the probe and exit the function if it fails. This prevents the tp structure from being used after it is freed. Link: http://lkml.kernel.org/r/20130704034038.819592356@goodmis.org Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-07-04 07:33:50 +04:00
return -EBUSY;
unreg:
__unregister_trace_kprobe(tk);
dyn_event_remove(&tk->devent);
trace_probe_unlink(&tk->tp);
return 0;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
struct trace_kprobe *comp)
{
struct trace_probe_event *tpe = orig->tp.event;
struct trace_probe *pos;
int i;
list_for_each_entry(pos, &tpe->probes, list) {
orig = container_of(pos, struct trace_kprobe, tp);
if (strcmp(trace_kprobe_symbol(orig),
trace_kprobe_symbol(comp)) ||
trace_kprobe_offset(orig) != trace_kprobe_offset(comp))
continue;
/*
* trace_probe_compare_arg_type() ensured that nr_args and
* each argument name and type are same. Let's compare comm.
*/
for (i = 0; i < orig->tp.nr_args; i++) {
if (strcmp(orig->tp.args[i].comm,
comp->tp.args[i].comm))
break;
}
if (i == orig->tp.nr_args)
return true;
}
return false;
}
static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to)
{
int ret;
ret = trace_probe_compare_arg_type(&tk->tp, &to->tp);
if (ret) {
/* Note that argument starts index = 2 */
trace_probe_log_set_index(ret + 1);
trace_probe_log_err(0, DIFF_ARG_TYPE);
return -EEXIST;
}
if (trace_kprobe_has_same_kprobe(to, tk)) {
trace_probe_log_set_index(0);
trace_probe_log_err(0, SAME_PROBE);
return -EEXIST;
}
/* Append to existing event */
ret = trace_probe_append(&tk->tp, &to->tp);
if (ret)
return ret;
/* Register k*probe */
ret = __register_trace_kprobe(tk);
if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
ret = 0;
}
if (ret)
trace_probe_unlink(&tk->tp);
else
dyn_event_add(&tk->devent);
return ret;
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/* Register a trace_probe and probe_event */
static int register_trace_kprobe(struct trace_kprobe *tk)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct trace_kprobe *old_tk;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
int ret;
mutex_lock(&event_mutex);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
old_tk = find_trace_kprobe(trace_probe_name(&tk->tp),
trace_probe_group_name(&tk->tp));
if (old_tk) {
if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) {
trace_probe_log_set_index(0);
trace_probe_log_err(0, DIFF_PROBE_TYPE);
ret = -EEXIST;
} else {
ret = append_trace_kprobe(tk, old_tk);
}
goto end;
}
/* Register new event */
ret = register_kprobe_event(tk);
if (ret) {
pr_warn("Failed to register probe event(%d)\n", ret);
goto end;
}
/* Register k*probe */
ret = __register_trace_kprobe(tk);
if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
ret = 0;
}
if (ret < 0)
unregister_kprobe_event(tk);
else
dyn_event_add(&tk->devent);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
end:
mutex_unlock(&event_mutex);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
return ret;
}
/* Module notifier call back, checking event on the module */
static int trace_kprobe_module_callback(struct notifier_block *nb,
unsigned long val, void *data)
{
struct module *mod = data;
struct dyn_event *pos;
struct trace_kprobe *tk;
int ret;
if (val != MODULE_STATE_COMING)
return NOTIFY_DONE;
/* Update probes on coming module */
mutex_lock(&event_mutex);
for_each_trace_kprobe(tk, pos) {
if (trace_kprobe_within_module(tk, mod)) {
/* Don't need to check busy - this should have gone. */
__unregister_trace_kprobe(tk);
ret = __register_trace_kprobe(tk);
if (ret)
pr_warn("Failed to re-register probe %s on %s: %d\n",
trace_probe_name(&tk->tp),
module_name(mod), ret);
}
}
mutex_unlock(&event_mutex);
return NOTIFY_DONE;
}
static struct notifier_block trace_kprobe_module_nb = {
.notifier_call = trace_kprobe_module_callback,
.priority = 1 /* Invoked after kprobe module callback */
};
/* Convert certain expected symbols into '_' when generating event names */
static inline void sanitize_event_name(char *name)
{
while (*name++ != '\0')
if (*name == ':' || *name == '.')
*name = '_';
}
static int trace_kprobe_create(int argc, const char *argv[])
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
/*
* Argument syntax:
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
* - Add kprobe:
* p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
* - Add kretprobe:
* r[MAXACTIVE][:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS]
* Or
* p:[GRP/]EVENT] [MOD:]KSYM[+0]%return [FETCHARGS]
*
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
* Fetch args:
* $retval : fetch return value
* $stack : fetch stack address
* $stackN : fetch Nth of stack (N:0-)
* $comm : fetch current task comm
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
* @ADDR : fetch memory at ADDR (ADDR should be in kernel)
* @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
* %REG : fetch register REG
* Dereferencing memory fetch:
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
* +|-offs(ARG) : fetch memory at ARG +|- offs address.
* Alias name of args:
* NAME=FETCHARG : set NAME as alias of FETCHARG.
* Type of args:
* FETCHARG:TYPE : use TYPE instead of unsigned long.
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
*/
struct trace_kprobe *tk = NULL;
int i, len, ret = 0;
bool is_return = false;
char *symbol = NULL, *tmp = NULL;
const char *event = NULL, *group = KPROBE_EVENT_SYSTEM;
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
int maxactive = 0;
long offset = 0;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
void *addr = NULL;
char buf[MAX_EVENT_NAME_LEN];
unsigned int flags = TPARG_FL_KERNEL;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create() It is possible to trigger a NULL pointer dereference by writing an incorrectly formatted string to krpobe_events (trying to create a kretprobe omitting the symbol). Example: echo "r:event_1 " >> /sys/kernel/debug/tracing/kprobe_events That triggers this: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 #PF error: [normal kernel read fault] PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 6 PID: 1757 Comm: bash Not tainted 5.0.0-rc1+ #125 Hardware name: Dell Inc. XPS 13 9370/0F6P3V, BIOS 1.5.1 08/09/2018 RIP: 0010:kstrtoull+0x2/0x20 Code: 28 00 00 00 75 17 48 83 c4 18 5b 41 5c 5d c3 b8 ea ff ff ff eb e1 b8 de ff ff ff eb da e8 d6 36 bb ff 66 0f 1f 44 00 00 31 c0 <80> 3f 2b 55 48 89 e5 0f 94 c0 48 01 c7 e8 5c ff ff ff 5d c3 66 2e RSP: 0018:ffffb5d482e57cb8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff82b12720 RDX: ffffb5d482e57cf8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffb5d482e57d70 R08: ffffa0c05e5a7080 R09: ffffa0c05e003980 R10: 0000000000000000 R11: 0000000040000000 R12: ffffa0c04fe87b08 R13: 0000000000000001 R14: 000000000000000b R15: ffffa0c058d749e1 FS: 00007f137c7f7740(0000) GS:ffffa0c05e580000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000497d46004 CR4: 00000000003606e0 Call Trace: ? trace_kprobe_create+0xb6/0x840 ? _cond_resched+0x19/0x40 ? _cond_resched+0x19/0x40 ? __kmalloc+0x62/0x210 ? argv_split+0x8f/0x140 ? trace_kprobe_create+0x840/0x840 ? trace_kprobe_create+0x840/0x840 create_or_delete_trace_kprobe+0x11/0x30 trace_run_command+0x50/0x90 trace_parse_run_command+0xc1/0x160 probes_write+0x10/0x20 __vfs_write+0x3a/0x1b0 ? apparmor_file_permission+0x1a/0x20 ? security_file_permission+0x31/0xf0 ? _cond_resched+0x19/0x40 vfs_write+0xb1/0x1a0 ksys_write+0x55/0xc0 __x64_sys_write+0x1a/0x20 do_syscall_64+0x5a/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fix by doing the proper argument checks in trace_kprobe_create(). Cc: Ingo Molnar <mingo@redhat.com> Link: https://lore.kernel.org/lkml/20190111095108.b79a2ee026185cbd62365977@kernel.org Link: http://lkml.kernel.org/r/20190111060113.GA22841@xps-13 Fixes: 6212dd29683e ("tracing/kprobes: Use dyn_event framework for kprobe events") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-11 09:01:13 +03:00
switch (argv[0][0]) {
case 'r':
is_return = true;
tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create() It is possible to trigger a NULL pointer dereference by writing an incorrectly formatted string to krpobe_events (trying to create a kretprobe omitting the symbol). Example: echo "r:event_1 " >> /sys/kernel/debug/tracing/kprobe_events That triggers this: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 #PF error: [normal kernel read fault] PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 6 PID: 1757 Comm: bash Not tainted 5.0.0-rc1+ #125 Hardware name: Dell Inc. XPS 13 9370/0F6P3V, BIOS 1.5.1 08/09/2018 RIP: 0010:kstrtoull+0x2/0x20 Code: 28 00 00 00 75 17 48 83 c4 18 5b 41 5c 5d c3 b8 ea ff ff ff eb e1 b8 de ff ff ff eb da e8 d6 36 bb ff 66 0f 1f 44 00 00 31 c0 <80> 3f 2b 55 48 89 e5 0f 94 c0 48 01 c7 e8 5c ff ff ff 5d c3 66 2e RSP: 0018:ffffb5d482e57cb8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff82b12720 RDX: ffffb5d482e57cf8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffb5d482e57d70 R08: ffffa0c05e5a7080 R09: ffffa0c05e003980 R10: 0000000000000000 R11: 0000000040000000 R12: ffffa0c04fe87b08 R13: 0000000000000001 R14: 000000000000000b R15: ffffa0c058d749e1 FS: 00007f137c7f7740(0000) GS:ffffa0c05e580000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000497d46004 CR4: 00000000003606e0 Call Trace: ? trace_kprobe_create+0xb6/0x840 ? _cond_resched+0x19/0x40 ? _cond_resched+0x19/0x40 ? __kmalloc+0x62/0x210 ? argv_split+0x8f/0x140 ? trace_kprobe_create+0x840/0x840 ? trace_kprobe_create+0x840/0x840 create_or_delete_trace_kprobe+0x11/0x30 trace_run_command+0x50/0x90 trace_parse_run_command+0xc1/0x160 probes_write+0x10/0x20 __vfs_write+0x3a/0x1b0 ? apparmor_file_permission+0x1a/0x20 ? security_file_permission+0x31/0xf0 ? _cond_resched+0x19/0x40 vfs_write+0xb1/0x1a0 ksys_write+0x55/0xc0 __x64_sys_write+0x1a/0x20 do_syscall_64+0x5a/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fix by doing the proper argument checks in trace_kprobe_create(). Cc: Ingo Molnar <mingo@redhat.com> Link: https://lore.kernel.org/lkml/20190111095108.b79a2ee026185cbd62365977@kernel.org Link: http://lkml.kernel.org/r/20190111060113.GA22841@xps-13 Fixes: 6212dd29683e ("tracing/kprobes: Use dyn_event framework for kprobe events") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-11 09:01:13 +03:00
break;
case 'p':
break;
default:
return -ECANCELED;
}
if (argc < 2)
return -ECANCELED;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_probe_log_init("trace_kprobe", argc, argv);
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
event = strchr(&argv[0][1], ':');
if (event)
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
event++;
if (isdigit(argv[0][1])) {
if (!is_return) {
trace_probe_log_err(1, MAXACT_NO_KPROBE);
goto parse_error;
}
if (event)
len = event - &argv[0][1] - 1;
else
len = strlen(&argv[0][1]);
if (len > MAX_EVENT_NAME_LEN - 1) {
trace_probe_log_err(1, BAD_MAXACT);
goto parse_error;
}
memcpy(buf, &argv[0][1], len);
buf[len] = '\0';
ret = kstrtouint(buf, 0, &maxactive);
if (ret || !maxactive) {
trace_probe_log_err(1, BAD_MAXACT);
goto parse_error;
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
}
/* kretprobes instances are iterated over via a list. The
* maximum should stay reasonable.
*/
if (maxactive > KRETPROBE_MAXACTIVE_MAX) {
trace_probe_log_err(1, MAXACT_TOO_BIG);
goto parse_error;
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
}
}
/* try to parse an address. if that fails, try to read the
* input as a symbol. */
if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) {
trace_probe_log_set_index(1);
/* Check whether uprobe event specified */
if (strchr(argv[1], '/') && strchr(argv[1], ':')) {
ret = -ECANCELED;
goto error;
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/* a symbol specified */
symbol = kstrdup(argv[1], GFP_KERNEL);
if (!symbol)
return -ENOMEM;
tmp = strchr(symbol, '%');
if (tmp) {
if (!strcmp(tmp, "%return")) {
*tmp = '\0';
is_return = true;
} else {
trace_probe_log_err(tmp - symbol, BAD_ADDR_SUFFIX);
goto parse_error;
}
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/* TODO: support .init module functions */
ret = traceprobe_split_symbol_offset(symbol, &offset);
if (ret || offset < 0 || offset > UINT_MAX) {
trace_probe_log_err(0, BAD_PROBE_ADDR);
goto parse_error;
}
if (is_return)
flags |= TPARG_FL_RETURN;
if (kprobe_on_func_entry(NULL, symbol, offset))
flags |= TPARG_FL_FENTRY;
if (offset && is_return && !(flags & TPARG_FL_FENTRY)) {
trace_probe_log_err(0, BAD_RETPROBE);
goto parse_error;
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
trace_probe_log_set_index(0);
if (event) {
ret = traceprobe_parse_event_name(&event, &group, buf,
event - argv[0]);
if (ret)
goto parse_error;
} else {
/* Make a new event name */
if (symbol)
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
is_return ? 'r' : 'p', symbol, offset);
else
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
is_return ? 'r' : 'p', addr);
sanitize_event_name(buf);
event = buf;
}
/* setup a probe */
tracing/kprobes: expose maxactive for kretprobe in kprobe_events When a kretprobe is installed on a kernel function, there is a maximum limit of how many calls in parallel it can catch (aka "maxactive"). A kernel module could call register_kretprobe() and initialize maxactive (see example in samples/kprobes/kretprobe_example.c). But that is not exposed to userspace and it is currently not possible to choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events The default maxactive can be as low as 1 on single-core with a non-preemptive kernel. This is too low and we need to increase it not only for recursive functions, but for functions that sleep or resched. This patch updates the format of the command that can be written to kprobe_events so that maxactive can be optionally specified. I need this for a bpf program attached to the kretprobe of inet_csk_accept, which can sleep for a long time. This patch includes a basic selftest: > # ./ftracetest -v test.d/kprobe/ > === Ftrace unit tests === > [1] Kprobe dynamic event - adding and removing [PASS] > [2] Kprobe dynamic event - busy event check [PASS] > [3] Kprobe dynamic event with arguments [PASS] > [4] Kprobes event arguments with types [PASS] > [5] Kprobe dynamic event with function tracer [PASS] > [6] Kretprobe dynamic event with arguments [PASS] > [7] Kretprobe dynamic event with maxactive [PASS] > > # of passed: 7 > # of failed: 0 > # of unresolved: 0 > # of untested: 0 > # of unsupported: 0 > # of xfailed: 0 > # of undefined(test bug): 0 BugLink: https://github.com/iovisor/bcc/issues/1072 Link: http://lkml.kernel.org/r/1491215782-15490-1-git-send-email-alban@kinvolk.io Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Alban Crequy <alban@kinvolk.io> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 13:36:22 +03:00
tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive,
argc - 2, is_return);
if (IS_ERR(tk)) {
ret = PTR_ERR(tk);
/* This must return -ENOMEM, else there is a bug */
WARN_ON_ONCE(ret != -ENOMEM);
goto out; /* We know tk is not allocated */
}
argc -= 2; argv += 2;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/* parse arguments */
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
tmp = kstrdup(argv[i], GFP_KERNEL);
if (!tmp) {
ret = -ENOMEM;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
goto error;
}
trace_probe_log_set_index(i + 2);
ret = traceprobe_parse_probe_arg(&tk->tp, i, tmp, flags);
kfree(tmp);
if (ret)
goto error; /* This can be -ENOMEM */
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
ret = traceprobe_set_print_fmt(&tk->tp, is_return);
if (ret < 0)
goto error;
ret = register_trace_kprobe(tk);
if (ret) {
trace_probe_log_set_index(1);
if (ret == -EILSEQ)
trace_probe_log_err(0, BAD_INSN_BNDRY);
else if (ret == -ENOENT)
trace_probe_log_err(0, BAD_PROBE_ADDR);
else if (ret != -ENOMEM && ret != -EEXIST)
trace_probe_log_err(0, FAIL_REG_PROBE);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
goto error;
}
out:
trace_probe_log_clear();
kfree(symbol);
return ret;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
parse_error:
ret = -EINVAL;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
error:
free_trace_kprobe(tk);
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static int create_or_delete_trace_kprobe(int argc, char **argv)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
int ret;
if (argv[0][0] == '-')
return dyn_event_release(argc, argv, &trace_kprobe_ops);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
ret = trace_kprobe_create(argc, (const char **)argv);
return ret == -ECANCELED ? -EINVAL : ret;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static int trace_kprobe_run_command(struct dynevent_cmd *cmd)
{
return trace_run_command(cmd->seq.buffer, create_or_delete_trace_kprobe);
}
/**
* kprobe_event_cmd_init - Initialize a kprobe event command object
* @cmd: A pointer to the dynevent_cmd struct representing the new event
* @buf: A pointer to the buffer used to build the command
* @maxlen: The length of the buffer passed in @buf
*
* Initialize a synthetic event command object. Use this before
* calling any of the other kprobe_event functions.
*/
void kprobe_event_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen)
{
dynevent_cmd_init(cmd, buf, maxlen, DYNEVENT_TYPE_KPROBE,
trace_kprobe_run_command);
}
EXPORT_SYMBOL_GPL(kprobe_event_cmd_init);
/**
* __kprobe_event_gen_cmd_start - Generate a kprobe event command from arg list
* @cmd: A pointer to the dynevent_cmd struct representing the new event
* @name: The name of the kprobe event
* @loc: The location of the kprobe event
* @kretprobe: Is this a return probe?
* @args: Variable number of arg (pairs), one pair for each field
*
* NOTE: Users normally won't want to call this function directly, but
* rather use the kprobe_event_gen_cmd_start() wrapper, which automatically
* adds a NULL to the end of the arg list. If this function is used
* directly, make sure the last arg in the variable arg list is NULL.
*
* Generate a kprobe event command to be executed by
* kprobe_event_gen_cmd_end(). This function can be used to generate the
* complete command or only the first part of it; in the latter case,
* kprobe_event_add_fields() can be used to add more fields following this.
*
* Unlikely the synth_event_gen_cmd_start(), @loc must be specified. This
* returns -EINVAL if @loc == NULL.
*
* Return: 0 if successful, error otherwise.
*/
int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd, bool kretprobe,
const char *name, const char *loc, ...)
{
char buf[MAX_EVENT_NAME_LEN];
struct dynevent_arg arg;
va_list args;
int ret;
if (cmd->type != DYNEVENT_TYPE_KPROBE)
return -EINVAL;
if (!loc)
return -EINVAL;
if (kretprobe)
snprintf(buf, MAX_EVENT_NAME_LEN, "r:kprobes/%s", name);
else
snprintf(buf, MAX_EVENT_NAME_LEN, "p:kprobes/%s", name);
ret = dynevent_str_add(cmd, buf);
if (ret)
return ret;
dynevent_arg_init(&arg, 0);
arg.str = loc;
ret = dynevent_arg_add(cmd, &arg, NULL);
if (ret)
return ret;
va_start(args, loc);
for (;;) {
const char *field;
field = va_arg(args, const char *);
if (!field)
break;
if (++cmd->n_fields > MAX_TRACE_ARGS) {
ret = -EINVAL;
break;
}
arg.str = field;
ret = dynevent_arg_add(cmd, &arg, NULL);
if (ret)
break;
}
va_end(args);
return ret;
}
EXPORT_SYMBOL_GPL(__kprobe_event_gen_cmd_start);
/**
* __kprobe_event_add_fields - Add probe fields to a kprobe command from arg list
* @cmd: A pointer to the dynevent_cmd struct representing the new event
* @args: Variable number of arg (pairs), one pair for each field
*
* NOTE: Users normally won't want to call this function directly, but
* rather use the kprobe_event_add_fields() wrapper, which
* automatically adds a NULL to the end of the arg list. If this
* function is used directly, make sure the last arg in the variable
* arg list is NULL.
*
* Add probe fields to an existing kprobe command using a variable
* list of args. Fields are added in the same order they're listed.
*
* Return: 0 if successful, error otherwise.
*/
int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...)
{
struct dynevent_arg arg;
va_list args;
int ret = 0;
if (cmd->type != DYNEVENT_TYPE_KPROBE)
return -EINVAL;
dynevent_arg_init(&arg, 0);
va_start(args, cmd);
for (;;) {
const char *field;
field = va_arg(args, const char *);
if (!field)
break;
if (++cmd->n_fields > MAX_TRACE_ARGS) {
ret = -EINVAL;
break;
}
arg.str = field;
ret = dynevent_arg_add(cmd, &arg, NULL);
if (ret)
break;
}
va_end(args);
return ret;
}
EXPORT_SYMBOL_GPL(__kprobe_event_add_fields);
/**
* kprobe_event_delete - Delete a kprobe event
* @name: The name of the kprobe event to delete
*
* Delete a kprobe event with the give @name from kernel code rather
* than directly from the command line.
*
* Return: 0 if successful, error otherwise.
*/
int kprobe_event_delete(const char *name)
{
char buf[MAX_EVENT_NAME_LEN];
snprintf(buf, MAX_EVENT_NAME_LEN, "-:%s", name);
return trace_run_command(buf, create_or_delete_trace_kprobe);
}
EXPORT_SYMBOL_GPL(kprobe_event_delete);
static int trace_kprobe_release(struct dyn_event *ev)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct trace_kprobe *tk = to_trace_kprobe(ev);
int ret = unregister_trace_kprobe(tk);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (!ret)
free_trace_kprobe(tk);
return ret;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct trace_kprobe *tk = to_trace_kprobe(ev);
int i;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p');
if (trace_kprobe_is_return(tk) && tk->rp.maxactive)
seq_printf(m, "%d", tk->rp.maxactive);
seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp),
trace_probe_name(&tk->tp));
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (!tk->symbol)
seq_printf(m, " 0x%p", tk->rp.kp.addr);
else if (tk->rp.kp.offset)
seq_printf(m, " %s+%u", trace_kprobe_symbol(tk),
tk->rp.kp.offset);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
else
seq_printf(m, " %s", trace_kprobe_symbol(tk));
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
for (i = 0; i < tk->tp.nr_args; i++)
seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm);
seq_putc(m, '\n');
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
return 0;
}
static int probes_seq_show(struct seq_file *m, void *v)
{
struct dyn_event *ev = v;
if (!is_trace_kprobe(ev))
return 0;
return trace_kprobe_show(m, ev);
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
static const struct seq_operations probes_seq_op = {
.start = dyn_event_seq_start,
.next = dyn_event_seq_next,
.stop = dyn_event_seq_stop,
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
.show = probes_seq_show
};
static int probes_open(struct inode *inode, struct file *file)
{
int ret;
ret = security_locked_down(LOCKDOWN_TRACEFS);
if (ret)
return ret;
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
ret = dyn_events_release_all(&trace_kprobe_ops);
if (ret < 0)
return ret;
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
return seq_open(file, &probes_seq_op);
}
static ssize_t probes_write(struct file *file, const char __user *buffer,
size_t count, loff_t *ppos)
{
return trace_parse_run_command(file, buffer, count, ppos,
create_or_delete_trace_kprobe);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static const struct file_operations kprobe_events_ops = {
.owner = THIS_MODULE,
.open = probes_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
.write = probes_write,
};
/* Probes profiling interfaces */
static int probes_profile_seq_show(struct seq_file *m, void *v)
{
struct dyn_event *ev = v;
struct trace_kprobe *tk;
if (!is_trace_kprobe(ev))
return 0;
tk = to_trace_kprobe(ev);
seq_printf(m, " %-44s %15lu %15lu\n",
trace_probe_name(&tk->tp),
trace_kprobe_nhit(tk),
tk->rp.kp.nmissed);
return 0;
}
static const struct seq_operations profile_seq_op = {
.start = dyn_event_seq_start,
.next = dyn_event_seq_next,
.stop = dyn_event_seq_stop,
.show = probes_profile_seq_show
};
static int profile_open(struct inode *inode, struct file *file)
{
int ret;
ret = security_locked_down(LOCKDOWN_TRACEFS);
if (ret)
return ret;
return seq_open(file, &profile_seq_op);
}
static const struct file_operations kprobe_profile_ops = {
.owner = THIS_MODULE,
.open = profile_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
/* Kprobe specific fetch functions */
/* Return the length of string -- including null terminal byte */
static nokprobe_inline int
fetch_store_strlen_user(unsigned long addr)
{
const void __user *uaddr = (__force const void __user *)addr;
return strnlen_user_nofault(uaddr, MAX_STRING_SIZE);
}
/* Return the length of string -- including null terminal byte */
static nokprobe_inline int
fetch_store_strlen(unsigned long addr)
{
int ret, len = 0;
u8 c;
#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
if (addr < TASK_SIZE)
return fetch_store_strlen_user(addr);
#endif
do {
ret = copy_from_kernel_nofault(&c, (u8 *)addr + len, 1);
len++;
} while (c && ret == 0 && len < MAX_STRING_SIZE);
return (ret < 0) ? ret : len;
}
/*
* Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
* with max length and relative data location.
*/
static nokprobe_inline int
fetch_store_string_user(unsigned long addr, void *dest, void *base)
{
const void __user *uaddr = (__force const void __user *)addr;
int maxlen = get_loc_len(*(u32 *)dest);
void *__dest;
long ret;
if (unlikely(!maxlen))
return -ENOMEM;
__dest = get_loc_data(dest, base);
ret = strncpy_from_user_nofault(__dest, uaddr, maxlen);
if (ret >= 0)
*(u32 *)dest = make_data_loc(ret, __dest - base);
return ret;
}
/*
* Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
* length and relative data location.
*/
static nokprobe_inline int
fetch_store_string(unsigned long addr, void *dest, void *base)
{
int maxlen = get_loc_len(*(u32 *)dest);
void *__dest;
long ret;
#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
if ((unsigned long)addr < TASK_SIZE)
return fetch_store_string_user(addr, dest, base);
#endif
if (unlikely(!maxlen))
return -ENOMEM;
__dest = get_loc_data(dest, base);
/*
* Try to get string again, since the string can be changed while
* probing.
*/
ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen);
if (ret >= 0)
*(u32 *)dest = make_data_loc(ret, __dest - base);
return ret;
}
static nokprobe_inline int
probe_mem_read_user(void *dest, void *src, size_t size)
{
const void __user *uaddr = (__force const void __user *)src;
return copy_from_user_nofault(dest, uaddr, size);
}
static nokprobe_inline int
probe_mem_read(void *dest, void *src, size_t size)
{
#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
if ((unsigned long)src < TASK_SIZE)
return probe_mem_read_user(dest, src, size);
#endif
return copy_from_kernel_nofault(dest, src, size);
}
/* Note that we don't verify it, since the code does not come from user space */
static int
process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
void *base)
{
unsigned long val;
retry:
/* 1st stage: get value from context */
switch (code->op) {
case FETCH_OP_REG:
val = regs_get_register(regs, code->param);
break;
case FETCH_OP_STACK:
val = regs_get_kernel_stack_nth(regs, code->param);
break;
case FETCH_OP_STACKP:
val = kernel_stack_pointer(regs);
break;
case FETCH_OP_RETVAL:
val = regs_return_value(regs);
break;
case FETCH_OP_IMM:
val = code->immediate;
break;
case FETCH_OP_COMM:
val = (unsigned long)current->comm;
break;
case FETCH_OP_DATA:
val = (unsigned long)code->data;
break;
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
case FETCH_OP_ARG:
val = regs_get_kernel_argument(regs, code->param);
break;
#endif
case FETCH_NOP_SYMBOL: /* Ignore a place holder */
code++;
goto retry;
default:
return -EILSEQ;
}
code++;
return process_fetch_insn_bottom(code, val, dest, base);
}
NOKPROBE_SYMBOL(process_fetch_insn)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/* Kprobe handler */
static nokprobe_inline void
__kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
struct trace_event_file *trace_file)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct kprobe_trace_entry_head *entry;
struct trace_event_call *call = trace_probe_event_call(&tk->tp);
struct trace_event_buffer fbuffer;
int dsize;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
WARN_ON(call != trace_file->event_call);
if (trace_trigger_soft_disabled(trace_file))
return;
local_save_flags(fbuffer.flags);
fbuffer.pc = preempt_count();
fbuffer.trace_file = trace_file;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
dsize = __get_data_size(&tk->tp, regs);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
fbuffer.event =
trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file,
call->event.type,
sizeof(*entry) + tk->tp.size + dsize,
fbuffer.flags, fbuffer.pc);
if (!fbuffer.event)
return;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
fbuffer.regs = regs;
entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
entry->ip = (unsigned long)tk->rp.kp.addr;
store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_event_buffer_commit(&fbuffer);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static void
kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs)
{
struct event_file_link *link;
trace_probe_for_each_link_rcu(link, &tk->tp)
__kprobe_trace_func(tk, regs, link->file);
}
NOKPROBE_SYMBOL(kprobe_trace_func);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/* Kretprobe handler */
static nokprobe_inline void
__kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
struct pt_regs *regs,
struct trace_event_file *trace_file)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct kretprobe_trace_entry_head *entry;
struct trace_event_buffer fbuffer;
struct trace_event_call *call = trace_probe_event_call(&tk->tp);
int dsize;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
WARN_ON(call != trace_file->event_call);
if (trace_trigger_soft_disabled(trace_file))
return;
local_save_flags(fbuffer.flags);
fbuffer.pc = preempt_count();
fbuffer.trace_file = trace_file;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
dsize = __get_data_size(&tk->tp, regs);
fbuffer.event =
trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file,
call->event.type,
sizeof(*entry) + tk->tp.size + dsize,
fbuffer.flags, fbuffer.pc);
if (!fbuffer.event)
return;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
fbuffer.regs = regs;
entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
entry->func = (unsigned long)tk->rp.kp.addr;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
entry->ret_ip = (unsigned long)ri->ret_addr;
store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_event_buffer_commit(&fbuffer);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static void
kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
struct pt_regs *regs)
{
struct event_file_link *link;
trace_probe_for_each_link_rcu(link, &tk->tp)
__kretprobe_trace_func(tk, ri, regs, link->file);
}
NOKPROBE_SYMBOL(kretprobe_trace_func);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
/* Event entry printers */
static enum print_line_t
print_kprobe_event(struct trace_iterator *iter, int flags,
struct trace_event *event)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct kprobe_trace_entry_head *field;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
struct trace_seq *s = &iter->seq;
struct trace_probe *tp;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
field = (struct kprobe_trace_entry_head *)iter->ent;
tp = trace_probe_primary_from_call(
container_of(event, struct trace_event_call, event));
if (WARN_ON_ONCE(!tp))
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_seq_printf(s, "%s: (", trace_probe_name(tp));
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_seq_putc(s, ')');
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (print_probe_args(s, tp->args, tp->nr_args,
(u8 *)&field[1], field) < 0)
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_seq_putc(s, '\n');
out:
return trace_handle_return(s);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static enum print_line_t
print_kretprobe_event(struct trace_iterator *iter, int flags,
struct trace_event *event)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct kretprobe_trace_entry_head *field;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
struct trace_seq *s = &iter->seq;
struct trace_probe *tp;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
field = (struct kretprobe_trace_entry_head *)iter->ent;
tp = trace_probe_primary_from_call(
container_of(event, struct trace_event_call, event));
if (WARN_ON_ONCE(!tp))
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_seq_printf(s, "%s: (", trace_probe_name(tp));
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_seq_puts(s, " <- ");
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_seq_putc(s, ')');
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (print_probe_args(s, tp->args, tp->nr_args,
(u8 *)&field[1], field) < 0)
goto out;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
trace_seq_putc(s, '\n');
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
out:
return trace_handle_return(s);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static int kprobe_event_define_fields(struct trace_event_call *event_call)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
int ret;
struct kprobe_trace_entry_head field;
struct trace_probe *tp;
tp = trace_probe_primary_from_call(event_call);
if (WARN_ON_ONCE(!tp))
return -ENOENT;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static int kretprobe_event_define_fields(struct trace_event_call *event_call)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
int ret;
struct kretprobe_trace_entry_head field;
struct trace_probe *tp;
tp = trace_probe_primary_from_call(event_call);
if (WARN_ON_ONCE(!tp))
return -ENOENT;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
#ifdef CONFIG_PERF_EVENTS
/* Kprobe profile handler */
static int
kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
{
struct trace_event_call *call = trace_probe_event_call(&tk->tp);
struct kprobe_trace_entry_head *entry;
struct hlist_head *head;
int size, __size, dsize;
int rctx;
if (bpf_prog_array_valid(call)) {
unsigned long orig_ip = instruction_pointer(regs);
int ret;
ret = trace_call_bpf(call, regs);
/*
* We need to check and see if we modified the pc of the
bpf/error-inject/kprobes: Clear current_kprobe and enable preempt in kprobe Clear current_kprobe and enable preemption in kprobe even if pre_handler returns !0. This simplifies function override using kprobes. Jprobe used to require to keep the preemption disabled and keep current_kprobe until it returned to original function entry. For this reason kprobe_int3_handler() and similar arch dependent kprobe handers checks pre_handler result and exit without enabling preemption if the result is !0. After removing the jprobe, Kprobes does not need to keep preempt disabled even if user handler returns !0 anymore. But since the function override handler in error-inject and bpf is also returns !0 if it overrides a function, to balancing the preempt count, it enables preemption and reset current kprobe by itself. That is a bad design that is very buggy. This fixes such unbalanced preempt-count and current_kprobes setting in kprobes, bpf and error-inject. Note: for powerpc and x86, this removes all preempt_disable from kprobe_ftrace_handler because ftrace callbacks are called under preempt disabled. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: James Hogan <jhogan@kernel.org> Cc: Josef Bacik <jbacik@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linuxppc-dev@lists.ozlabs.org Cc: sparclinux@vger.kernel.org Link: https://lore.kernel.org/lkml/152942494574.15209.12323837825873032258.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-19 19:15:45 +03:00
* pt_regs, and if so return 1 so that we don't do the
* single stepping.
*/
bpf/error-inject/kprobes: Clear current_kprobe and enable preempt in kprobe Clear current_kprobe and enable preemption in kprobe even if pre_handler returns !0. This simplifies function override using kprobes. Jprobe used to require to keep the preemption disabled and keep current_kprobe until it returned to original function entry. For this reason kprobe_int3_handler() and similar arch dependent kprobe handers checks pre_handler result and exit without enabling preemption if the result is !0. After removing the jprobe, Kprobes does not need to keep preempt disabled even if user handler returns !0 anymore. But since the function override handler in error-inject and bpf is also returns !0 if it overrides a function, to balancing the preempt count, it enables preemption and reset current kprobe by itself. That is a bad design that is very buggy. This fixes such unbalanced preempt-count and current_kprobes setting in kprobes, bpf and error-inject. Note: for powerpc and x86, this removes all preempt_disable from kprobe_ftrace_handler because ftrace callbacks are called under preempt disabled. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: James Hogan <jhogan@kernel.org> Cc: Josef Bacik <jbacik@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linuxppc-dev@lists.ozlabs.org Cc: sparclinux@vger.kernel.org Link: https://lore.kernel.org/lkml/152942494574.15209.12323837825873032258.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-19 19:15:45 +03:00
if (orig_ip != instruction_pointer(regs))
return 1;
if (!ret)
return 0;
}
tracing, perf: Implement BPF programs attached to kprobes BPF programs, attached to kprobes, provide a safe way to execute user-defined BPF byte-code programs without being able to crash or hang the kernel in any way. The BPF engine makes sure that such programs have a finite execution time and that they cannot break out of their sandbox. The user interface is to attach to a kprobe via the perf syscall: struct perf_event_attr attr = { .type = PERF_TYPE_TRACEPOINT, .config = event_id, ... }; event_fd = perf_event_open(&attr,...); ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); 'prog_fd' is a file descriptor associated with BPF program previously loaded. 'event_id' is an ID of the kprobe created. Closing 'event_fd': close(event_fd); ... automatically detaches BPF program from it. BPF programs can call in-kernel helper functions to: - lookup/update/delete elements in maps - probe_read - wraper of probe_kernel_read() used to access any kernel data structures BPF programs receive 'struct pt_regs *' as an input ('struct pt_regs' is architecture dependent) and return 0 to ignore the event and 1 to store kprobe event into the ring buffer. Note, kprobes are a fundamentally _not_ a stable kernel ABI, so BPF programs attached to kprobes must be recompiled for every kernel version and user must supply correct LINUX_VERSION_CODE in attr.kern_version during bpf_prog_load() call. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1427312966-8434-4-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 22:49:20 +03:00
head = this_cpu_ptr(call->perf_events);
if (hlist_empty(head))
return 0;
dsize = __get_data_size(&tk->tp, regs);
__size = sizeof(*entry) + tk->tp.size + dsize;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
entry = perf_trace_buf_alloc(size, NULL, &rctx);
if (!entry)
return 0;
entry->ip = (unsigned long)tk->rp.kp.addr;
memset(&entry[1], 0, dsize);
store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL);
return 0;
}
NOKPROBE_SYMBOL(kprobe_perf_func);
/* Kretprobe profile handler */
static void
kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
struct pt_regs *regs)
{
struct trace_event_call *call = trace_probe_event_call(&tk->tp);
struct kretprobe_trace_entry_head *entry;
struct hlist_head *head;
int size, __size, dsize;
int rctx;
if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs))
tracing, perf: Implement BPF programs attached to kprobes BPF programs, attached to kprobes, provide a safe way to execute user-defined BPF byte-code programs without being able to crash or hang the kernel in any way. The BPF engine makes sure that such programs have a finite execution time and that they cannot break out of their sandbox. The user interface is to attach to a kprobe via the perf syscall: struct perf_event_attr attr = { .type = PERF_TYPE_TRACEPOINT, .config = event_id, ... }; event_fd = perf_event_open(&attr,...); ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); 'prog_fd' is a file descriptor associated with BPF program previously loaded. 'event_id' is an ID of the kprobe created. Closing 'event_fd': close(event_fd); ... automatically detaches BPF program from it. BPF programs can call in-kernel helper functions to: - lookup/update/delete elements in maps - probe_read - wraper of probe_kernel_read() used to access any kernel data structures BPF programs receive 'struct pt_regs *' as an input ('struct pt_regs' is architecture dependent) and return 0 to ignore the event and 1 to store kprobe event into the ring buffer. Note, kprobes are a fundamentally _not_ a stable kernel ABI, so BPF programs attached to kprobes must be recompiled for every kernel version and user must supply correct LINUX_VERSION_CODE in attr.kern_version during bpf_prog_load() call. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1427312966-8434-4-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-25 22:49:20 +03:00
return;
head = this_cpu_ptr(call->perf_events);
if (hlist_empty(head))
return;
dsize = __get_data_size(&tk->tp, regs);
__size = sizeof(*entry) + tk->tp.size + dsize;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
tracing, perf_events: Protect the buffer from recursion in perf While tracing using events with perf, if one enables the lockdep:lock_acquire event, it will infect every other perf trace events. Basically, you can enable whatever set of trace events through perf but if this event is part of the set, the only result we can get is a long list of lock_acquire events of rcu read lock, and only that. This is because of a recursion inside perf. 1) When a trace event is triggered, it will fill a per cpu buffer and submit it to perf. 2) Perf will commit this event but will also protect some data using rcu_read_lock 3) A recursion appears: rcu_read_lock triggers a lock_acquire event that will fill the per cpu event and then submit the buffer to perf. 4) Perf detects a recursion and ignores it 5) Perf continues its work on the previous event, but its buffer has been overwritten by the lock_acquire event, it has then been turned into a lock_acquire event of rcu read lock Such scenario also happens with lock_release with rcu_read_unlock(). We could turn the rcu_read_lock() into __rcu_read_lock() to drop the lock debugging from perf fast path, but that would make us lose the rcu debugging and that doesn't prevent from other possible kind of recursion from perf in the future. This patch adds a recursion protection based on a counter on the perf trace per cpu buffers to solve the problem. -v2: Fixed lost whitespace, added reviewed-by tag Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Jason Baron <jbaron@redhat.com> LKML-Reference: <1257477185-7838-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-06 06:13:05 +03:00
entry = perf_trace_buf_alloc(size, NULL, &rctx);
if (!entry)
return;
entry->func = (unsigned long)tk->rp.kp.addr;
entry->ret_ip = (unsigned long)ri->ret_addr;
store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL);
}
NOKPROBE_SYMBOL(kretprobe_perf_func);
int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type,
const char **symbol, u64 *probe_offset,
u64 *probe_addr, bool perf_type_tracepoint)
{
const char *pevent = trace_event_name(event->tp_event);
const char *group = event->tp_event->class->system;
struct trace_kprobe *tk;
if (perf_type_tracepoint)
tk = find_trace_kprobe(pevent, group);
else
tk = trace_kprobe_primary_from_call(event->tp_event);
if (!tk)
return -EINVAL;
*fd_type = trace_kprobe_is_return(tk) ? BPF_FD_TYPE_KRETPROBE
: BPF_FD_TYPE_KPROBE;
if (tk->symbol) {
*symbol = tk->symbol;
*probe_offset = tk->rp.kp.offset;
*probe_addr = 0;
} else {
*symbol = NULL;
*probe_offset = 0;
*probe_addr = (unsigned long)tk->rp.kp.addr;
}
return 0;
}
#endif /* CONFIG_PERF_EVENTS */
/*
* called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex.
*
* kprobe_trace_self_tests_init() does enable_trace_probe/disable_trace_probe
* lockless, but we can't race with this __init function.
*/
static int kprobe_register(struct trace_event_call *event,
enum trace_reg type, void *data)
tracing: Remove per event trace registering This patch removes the register functions of TRACE_EVENT() to enable and disable tracepoints. The registering of a event is now down directly in the trace_events.c file. The tracepoint_probe_register() is now called directly. The prototypes are no longer type checked, but this should not be an issue since the tracepoints are created automatically by the macros. If a prototype is incorrect in the TRACE_EVENT() macro, then other macros will catch it. The trace_event_class structure now holds the probes to be called by the callbacks. This removes needing to have each event have a separate pointer for the probe. To handle kprobes and syscalls, since they register probes in a different manner, a "reg" field is added to the ftrace_event_class structure. If the "reg" field is assigned, then it will be called for enabling and disabling of the probe for either ftrace or perf. To let the reg function know what is happening, a new enum (trace_reg) is created that has the type of control that is needed. With this new rework, the 82 kernel events and 618 syscall events has their footprint dramatically lowered: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint 4900252 1057412 861512 6819176 680d68 vmlinux.regs The size went from 6863829 to 6819176, that's a total of 44K in savings. With tracepoints being continuously added, this is critical that the footprint becomes minimal. v5: Added #ifdef CONFIG_PERF_EVENTS around a reference to perf specific structure in trace_events.c. v4: Fixed trace self tests to check probe because regfunc no longer exists. v3: Updated to handle void *data in beginning of probe parameters. Also added the tracepoint: check_trace_callback_type_##call(). v2: Changed the callback probes to pass void * and typecast the value within the function. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-21 20:27:06 +04:00
{
struct trace_event_file *file = data;
tracing: Remove per event trace registering This patch removes the register functions of TRACE_EVENT() to enable and disable tracepoints. The registering of a event is now down directly in the trace_events.c file. The tracepoint_probe_register() is now called directly. The prototypes are no longer type checked, but this should not be an issue since the tracepoints are created automatically by the macros. If a prototype is incorrect in the TRACE_EVENT() macro, then other macros will catch it. The trace_event_class structure now holds the probes to be called by the callbacks. This removes needing to have each event have a separate pointer for the probe. To handle kprobes and syscalls, since they register probes in a different manner, a "reg" field is added to the ftrace_event_class structure. If the "reg" field is assigned, then it will be called for enabling and disabling of the probe for either ftrace or perf. To let the reg function know what is happening, a new enum (trace_reg) is created that has the type of control that is needed. With this new rework, the 82 kernel events and 618 syscall events has their footprint dramatically lowered: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint 4900252 1057412 861512 6819176 680d68 vmlinux.regs The size went from 6863829 to 6819176, that's a total of 44K in savings. With tracepoints being continuously added, this is critical that the footprint becomes minimal. v5: Added #ifdef CONFIG_PERF_EVENTS around a reference to perf specific structure in trace_events.c. v4: Fixed trace self tests to check probe because regfunc no longer exists. v3: Updated to handle void *data in beginning of probe parameters. Also added the tracepoint: check_trace_callback_type_##call(). v2: Changed the callback probes to pass void * and typecast the value within the function. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-21 20:27:06 +04:00
switch (type) {
case TRACE_REG_REGISTER:
return enable_trace_kprobe(event, file);
tracing: Remove per event trace registering This patch removes the register functions of TRACE_EVENT() to enable and disable tracepoints. The registering of a event is now down directly in the trace_events.c file. The tracepoint_probe_register() is now called directly. The prototypes are no longer type checked, but this should not be an issue since the tracepoints are created automatically by the macros. If a prototype is incorrect in the TRACE_EVENT() macro, then other macros will catch it. The trace_event_class structure now holds the probes to be called by the callbacks. This removes needing to have each event have a separate pointer for the probe. To handle kprobes and syscalls, since they register probes in a different manner, a "reg" field is added to the ftrace_event_class structure. If the "reg" field is assigned, then it will be called for enabling and disabling of the probe for either ftrace or perf. To let the reg function know what is happening, a new enum (trace_reg) is created that has the type of control that is needed. With this new rework, the 82 kernel events and 618 syscall events has their footprint dramatically lowered: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint 4900252 1057412 861512 6819176 680d68 vmlinux.regs The size went from 6863829 to 6819176, that's a total of 44K in savings. With tracepoints being continuously added, this is critical that the footprint becomes minimal. v5: Added #ifdef CONFIG_PERF_EVENTS around a reference to perf specific structure in trace_events.c. v4: Fixed trace self tests to check probe because regfunc no longer exists. v3: Updated to handle void *data in beginning of probe parameters. Also added the tracepoint: check_trace_callback_type_##call(). v2: Changed the callback probes to pass void * and typecast the value within the function. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-21 20:27:06 +04:00
case TRACE_REG_UNREGISTER:
return disable_trace_kprobe(event, file);
tracing: Remove per event trace registering This patch removes the register functions of TRACE_EVENT() to enable and disable tracepoints. The registering of a event is now down directly in the trace_events.c file. The tracepoint_probe_register() is now called directly. The prototypes are no longer type checked, but this should not be an issue since the tracepoints are created automatically by the macros. If a prototype is incorrect in the TRACE_EVENT() macro, then other macros will catch it. The trace_event_class structure now holds the probes to be called by the callbacks. This removes needing to have each event have a separate pointer for the probe. To handle kprobes and syscalls, since they register probes in a different manner, a "reg" field is added to the ftrace_event_class structure. If the "reg" field is assigned, then it will be called for enabling and disabling of the probe for either ftrace or perf. To let the reg function know what is happening, a new enum (trace_reg) is created that has the type of control that is needed. With this new rework, the 82 kernel events and 618 syscall events has their footprint dramatically lowered: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint 4900252 1057412 861512 6819176 680d68 vmlinux.regs The size went from 6863829 to 6819176, that's a total of 44K in savings. With tracepoints being continuously added, this is critical that the footprint becomes minimal. v5: Added #ifdef CONFIG_PERF_EVENTS around a reference to perf specific structure in trace_events.c. v4: Fixed trace self tests to check probe because regfunc no longer exists. v3: Updated to handle void *data in beginning of probe parameters. Also added the tracepoint: check_trace_callback_type_##call(). v2: Changed the callback probes to pass void * and typecast the value within the function. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-21 20:27:06 +04:00
#ifdef CONFIG_PERF_EVENTS
case TRACE_REG_PERF_REGISTER:
return enable_trace_kprobe(event, NULL);
tracing: Remove per event trace registering This patch removes the register functions of TRACE_EVENT() to enable and disable tracepoints. The registering of a event is now down directly in the trace_events.c file. The tracepoint_probe_register() is now called directly. The prototypes are no longer type checked, but this should not be an issue since the tracepoints are created automatically by the macros. If a prototype is incorrect in the TRACE_EVENT() macro, then other macros will catch it. The trace_event_class structure now holds the probes to be called by the callbacks. This removes needing to have each event have a separate pointer for the probe. To handle kprobes and syscalls, since they register probes in a different manner, a "reg" field is added to the ftrace_event_class structure. If the "reg" field is assigned, then it will be called for enabling and disabling of the probe for either ftrace or perf. To let the reg function know what is happening, a new enum (trace_reg) is created that has the type of control that is needed. With this new rework, the 82 kernel events and 618 syscall events has their footprint dramatically lowered: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint 4900252 1057412 861512 6819176 680d68 vmlinux.regs The size went from 6863829 to 6819176, that's a total of 44K in savings. With tracepoints being continuously added, this is critical that the footprint becomes minimal. v5: Added #ifdef CONFIG_PERF_EVENTS around a reference to perf specific structure in trace_events.c. v4: Fixed trace self tests to check probe because regfunc no longer exists. v3: Updated to handle void *data in beginning of probe parameters. Also added the tracepoint: check_trace_callback_type_##call(). v2: Changed the callback probes to pass void * and typecast the value within the function. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-21 20:27:06 +04:00
case TRACE_REG_PERF_UNREGISTER:
return disable_trace_kprobe(event, NULL);
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
case TRACE_REG_PERF_ADD:
case TRACE_REG_PERF_DEL:
return 0;
tracing: Remove per event trace registering This patch removes the register functions of TRACE_EVENT() to enable and disable tracepoints. The registering of a event is now down directly in the trace_events.c file. The tracepoint_probe_register() is now called directly. The prototypes are no longer type checked, but this should not be an issue since the tracepoints are created automatically by the macros. If a prototype is incorrect in the TRACE_EVENT() macro, then other macros will catch it. The trace_event_class structure now holds the probes to be called by the callbacks. This removes needing to have each event have a separate pointer for the probe. To handle kprobes and syscalls, since they register probes in a different manner, a "reg" field is added to the ftrace_event_class structure. If the "reg" field is assigned, then it will be called for enabling and disabling of the probe for either ftrace or perf. To let the reg function know what is happening, a new enum (trace_reg) is created that has the type of control that is needed. With this new rework, the 82 kernel events and 618 syscall events has their footprint dramatically lowered: text data bss dec hex filename 4913961 1088356 861512 6863829 68bbd5 vmlinux.orig 4914025 1088868 861512 6864405 68be15 vmlinux.class 4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint 4900252 1057412 861512 6819176 680d68 vmlinux.regs The size went from 6863829 to 6819176, that's a total of 44K in savings. With tracepoints being continuously added, this is critical that the footprint becomes minimal. v5: Added #ifdef CONFIG_PERF_EVENTS around a reference to perf specific structure in trace_events.c. v4: Fixed trace self tests to check probe because regfunc no longer exists. v3: Updated to handle void *data in beginning of probe parameters. Also added the tracepoint: check_trace_callback_type_##call(). v2: Changed the callback probes to pass void * and typecast the value within the function. Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-21 20:27:06 +04:00
#endif
}
return 0;
}
static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
{
struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp);
int ret = 0;
kprobes: Optimize hot path by using percpu counter to collect 'nhit' statistics When doing ebpf+kprobe on some hot TCP functions (e.g. tcp_rcv_established), the kprobe_dispatcher() function shows up in 'perf report'. In kprobe_dispatcher(), there is a lot of cache bouncing on 'tk->nhit++'. 'tk->nhit' and 'tk->tp.flags' also share the same cacheline. perf report (cycles:pp): 8.30% ipv4_dst_check 4.74% copy_user_enhanced_fast_string 3.93% dst_release 2.80% tcp_v4_rcv 2.31% queued_spin_lock_slowpath 2.30% _raw_spin_lock 1.88% mlx4_en_process_rx_cq 1.84% eth_get_headlen 1.81% ip_rcv_finish ~~~~ 1.71% kprobe_dispatcher ~~~~ 1.55% mlx4_en_xmit 1.09% __probe_kernel_read perf report after patch: 9.15% ipv4_dst_check 5.00% copy_user_enhanced_fast_string 4.12% dst_release 2.96% tcp_v4_rcv 2.50% _raw_spin_lock 2.39% queued_spin_lock_slowpath 2.11% eth_get_headlen 2.03% mlx4_en_process_rx_cq 1.69% mlx4_en_xmit 1.19% ip_rcv_finish 1.12% __probe_kernel_read 1.02% ehci_hcd_cleanup Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Kernel Team <kernel-team@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1454531308-2441898-1-git-send-email-kafai@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 23:28:28 +03:00
raw_cpu_inc(*tk->nhit);
if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
kprobe_trace_func(tk, regs);
#ifdef CONFIG_PERF_EVENTS
if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
ret = kprobe_perf_func(tk, regs);
#endif
return ret;
}
NOKPROBE_SYMBOL(kprobe_dispatcher);
static int
kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
{
struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp);
kprobes: Optimize hot path by using percpu counter to collect 'nhit' statistics When doing ebpf+kprobe on some hot TCP functions (e.g. tcp_rcv_established), the kprobe_dispatcher() function shows up in 'perf report'. In kprobe_dispatcher(), there is a lot of cache bouncing on 'tk->nhit++'. 'tk->nhit' and 'tk->tp.flags' also share the same cacheline. perf report (cycles:pp): 8.30% ipv4_dst_check 4.74% copy_user_enhanced_fast_string 3.93% dst_release 2.80% tcp_v4_rcv 2.31% queued_spin_lock_slowpath 2.30% _raw_spin_lock 1.88% mlx4_en_process_rx_cq 1.84% eth_get_headlen 1.81% ip_rcv_finish ~~~~ 1.71% kprobe_dispatcher ~~~~ 1.55% mlx4_en_xmit 1.09% __probe_kernel_read perf report after patch: 9.15% ipv4_dst_check 5.00% copy_user_enhanced_fast_string 4.12% dst_release 2.96% tcp_v4_rcv 2.50% _raw_spin_lock 2.39% queued_spin_lock_slowpath 2.11% eth_get_headlen 2.03% mlx4_en_process_rx_cq 1.69% mlx4_en_xmit 1.19% ip_rcv_finish 1.12% __probe_kernel_read 1.02% ehci_hcd_cleanup Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Kernel Team <kernel-team@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1454531308-2441898-1-git-send-email-kafai@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 23:28:28 +03:00
raw_cpu_inc(*tk->nhit);
if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
kretprobe_trace_func(tk, ri, regs);
#ifdef CONFIG_PERF_EVENTS
if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
kretprobe_perf_func(tk, ri, regs);
#endif
return 0; /* We don't tweek kernel, so just return 0 */
}
NOKPROBE_SYMBOL(kretprobe_dispatcher);
static struct trace_event_functions kretprobe_funcs = {
.trace = print_kretprobe_event
};
static struct trace_event_functions kprobe_funcs = {
.trace = print_kprobe_event
};
ftrace: Rework event_create_dir() Rework event_create_dir() to use an array of static data instead of function pointers where possible. The problem is that it would call the function pointer on module load before parse_args(), possibly even before jump_labels were initialized. Luckily the generated functions don't use jump_labels but it still seems fragile. It also gets in the way of changing when we make the module map executable. The generated function are basically calling trace_define_field() with a bunch of static arguments. So instead of a function, capture these arguments in a static array, avoiding the function call. Now there are a number of cases where the fields are dynamic (syscall arguments, kprobes and uprobes), in which case a static array does not work, for these we preserve the function call. Luckily all these cases are not related to modules and so we can retain the function call for them. Also fix up all broken tracepoint definitions that now generate a compile error. Tested-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20191111132458.342979914@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-24 23:26:59 +03:00
static struct trace_event_fields kretprobe_fields_array[] = {
{ .type = TRACE_FUNCTION_TYPE,
.define_fields = kretprobe_event_define_fields },
{}
};
static struct trace_event_fields kprobe_fields_array[] = {
{ .type = TRACE_FUNCTION_TYPE,
.define_fields = kprobe_event_define_fields },
{}
};
static inline void init_trace_event_call(struct trace_kprobe *tk)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
struct trace_event_call *call = trace_probe_event_call(&tk->tp);
if (trace_kprobe_is_return(tk)) {
call->event.funcs = &kretprobe_funcs;
ftrace: Rework event_create_dir() Rework event_create_dir() to use an array of static data instead of function pointers where possible. The problem is that it would call the function pointer on module load before parse_args(), possibly even before jump_labels were initialized. Luckily the generated functions don't use jump_labels but it still seems fragile. It also gets in the way of changing when we make the module map executable. The generated function are basically calling trace_define_field() with a bunch of static arguments. So instead of a function, capture these arguments in a static array, avoiding the function call. Now there are a number of cases where the fields are dynamic (syscall arguments, kprobes and uprobes), in which case a static array does not work, for these we preserve the function call. Luckily all these cases are not related to modules and so we can retain the function call for them. Also fix up all broken tracepoint definitions that now generate a compile error. Tested-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20191111132458.342979914@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-24 23:26:59 +03:00
call->class->fields_array = kretprobe_fields_array;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
} else {
call->event.funcs = &kprobe_funcs;
ftrace: Rework event_create_dir() Rework event_create_dir() to use an array of static data instead of function pointers where possible. The problem is that it would call the function pointer on module load before parse_args(), possibly even before jump_labels were initialized. Luckily the generated functions don't use jump_labels but it still seems fragile. It also gets in the way of changing when we make the module map executable. The generated function are basically calling trace_define_field() with a bunch of static arguments. So instead of a function, capture these arguments in a static array, avoiding the function call. Now there are a number of cases where the fields are dynamic (syscall arguments, kprobes and uprobes), in which case a static array does not work, for these we preserve the function call. Luckily all these cases are not related to modules and so we can retain the function call for them. Also fix up all broken tracepoint definitions that now generate a compile error. Tested-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20191111132458.342979914@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-24 23:26:59 +03:00
call->class->fields_array = kprobe_fields_array;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
call->flags = TRACE_EVENT_FL_KPROBE;
call->class->reg = kprobe_register;
}
static int register_kprobe_event(struct trace_kprobe *tk)
{
init_trace_event_call(tk);
return trace_probe_register_event_call(&tk->tp);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
static int unregister_kprobe_event(struct trace_kprobe *tk)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
return trace_probe_unregister_event_call(&tk->tp);
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
}
#ifdef CONFIG_PERF_EVENTS
/* create a trace_kprobe, but don't add it to global lists */
struct trace_event_call *
create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
bool is_return)
{
struct trace_kprobe *tk;
int ret;
char *event;
/*
* local trace_kprobes are not added to dyn_event, so they are never
* searched in find_trace_kprobe(). Therefore, there is no concern of
* duplicated name here.
*/
event = func ? func : "DUMMY_EVENT";
tk = alloc_trace_kprobe(KPROBE_EVENT_SYSTEM, event, (void *)addr, func,
offs, 0 /* maxactive */, 0 /* nargs */,
is_return);
if (IS_ERR(tk)) {
pr_info("Failed to allocate trace_probe.(%d)\n",
(int)PTR_ERR(tk));
return ERR_CAST(tk);
}
init_trace_event_call(tk);
if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) {
ret = -ENOMEM;
goto error;
}
ret = __register_trace_kprobe(tk);
if (ret < 0)
goto error;
return trace_probe_event_call(&tk->tp);
error:
free_trace_kprobe(tk);
return ERR_PTR(ret);
}
void destroy_local_trace_kprobe(struct trace_event_call *event_call)
{
struct trace_kprobe *tk;
tk = trace_kprobe_primary_from_call(event_call);
if (unlikely(!tk))
return;
if (trace_probe_is_enabled(&tk->tp)) {
WARN_ON(1);
return;
}
__unregister_trace_kprobe(tk);
free_trace_kprobe(tk);
}
#endif /* CONFIG_PERF_EVENTS */
static __init void enable_boot_kprobe_events(void)
{
struct trace_array *tr = top_trace_array();
struct trace_event_file *file;
struct trace_kprobe *tk;
struct dyn_event *pos;
mutex_lock(&event_mutex);
for_each_trace_kprobe(tk, pos) {
list_for_each_entry(file, &tr->events, list)
if (file->event_call == trace_probe_event_call(&tk->tp))
trace_event_enable_disable(file, 1, 0);
}
mutex_unlock(&event_mutex);
}
static __init void setup_boot_kprobe_events(void)
{
char *p, *cmd = kprobe_boot_events_buf;
int ret;
strreplace(kprobe_boot_events_buf, ',', ' ');
while (cmd && *cmd != '\0') {
p = strchr(cmd, ';');
if (p)
*p++ = '\0';
ret = trace_run_command(cmd, create_or_delete_trace_kprobe);
if (ret)
pr_warn("Failed to add event(%d): %s\n", ret, cmd);
tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline When having kprobe trace event start up tests enabled and adding a kprobe_event on the kernel command line, it produced the following: trace_kprobe: Testing kprobe tracing: WARNING: CPU: 5 PID: 1 at kernel/trace/trace_kprobe.c:1724 kprobe_trace_self_tests_init+0x32d/0x36b Modules linked in: CPU: 5 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc1-test+ #249 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:kprobe_trace_self_tests_init+0x32d/0x36b Code: b7 e8 4f 8d a2 fe 85 c0 74 10 0f 0b 48 c7 c7 c8 1b 0d b7 ff c3 e8 19 af 99 fe 48 c7 c7 40 93 27 b7 e8 7f 1a a5 fe 85 c0 74 10 <0f> 0b 48 c7 c7 f8 1b 0d b7 ff c3 e8 f9 ae 9 a0 fe 85 RSP: 0018:ffffb36e40653e08 EFLAGS: 00010286 RAX: 00000000fffffff0 RBX: 0000000000000000 RCX: ffffb36e40653d5c RDX: 0000000000000000 RSI: ffffffffb72776e0 RDI: 0000000000000246 RBP: ffff98414fe58ff8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff98415d8aa940 R12: 0000000000000000 R13: ffffffffb737c1b0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff98415ea80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f959ce741b8 CR3: 000000011a210002 CR4: 00000000001606e0 Call Trace: ? init_kprobe_trace+0x19e/0x19e ? do_early_param+0x8e/0x8e do_one_initcall+0x6f/0x2b4 ? do_early_param+0x8e/0x8e kernel_init_freeable+0x21d/0x2c6 ? rest_init+0x146/0x146 kernel_init+0xa/0x10a ret_from_fork+0x3a/0x50 ---[ end trace 488430c083a4c956 ]--- As with the trace events, if a trace event is set on the kernel command line, the trace events start up tests are suspended. The kprobe start up tests should do the same when a kprobe is enabled on the kernel command line. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-24 02:50:34 +03:00
else
kprobe_boot_events_enabled = true;
cmd = p;
}
enable_boot_kprobe_events();
}
/*
* Register dynevent at core_initcall. This allows kernel to setup kprobe
* events in postcore_initcall without tracefs.
*/
static __init int init_kprobe_trace_early(void)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
{
int ret;
ret = dyn_event_register(&trace_kprobe_ops);
if (ret)
return ret;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (register_module_notifier(&trace_kprobe_module_nb))
return -EINVAL;
return 0;
}
core_initcall(init_kprobe_trace_early);
/* Make a tracefs interface for controlling probe points */
static __init int init_kprobe_trace(void)
{
int ret;
struct dentry *entry;
ret = tracing_init_dentry();
if (ret)
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
return 0;
entry = tracefs_create_file("kprobe_events", 0644, NULL,
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
NULL, &kprobe_events_ops);
/* Event list interface */
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (!entry)
pr_warn("Could not create tracefs 'kprobe_events' entry\n");
/* Profile interface */
entry = tracefs_create_file("kprobe_profile", 0444, NULL,
NULL, &kprobe_profile_ops);
if (!entry)
pr_warn("Could not create tracefs 'kprobe_profile' entry\n");
setup_boot_kprobe_events();
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
return 0;
}
fs_initcall(init_kprobe_trace);
#ifdef CONFIG_FTRACE_STARTUP_TEST
static __init struct trace_event_file *
find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr)
{
struct trace_event_file *file;
list_for_each_entry(file, &tr->events, list)
if (file->event_call == trace_probe_event_call(&tk->tp))
return file;
return NULL;
}
/*
* Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this
* stage, we can do this lockless.
*/
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
static __init int kprobe_trace_self_tests_init(void)
{
int ret, warn = 0;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
int (*target)(int, int, int, int, int, int);
struct trace_kprobe *tk;
struct trace_event_file *file;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
if (tracing_is_disabled())
return -ENODEV;
tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline When having kprobe trace event start up tests enabled and adding a kprobe_event on the kernel command line, it produced the following: trace_kprobe: Testing kprobe tracing: WARNING: CPU: 5 PID: 1 at kernel/trace/trace_kprobe.c:1724 kprobe_trace_self_tests_init+0x32d/0x36b Modules linked in: CPU: 5 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc1-test+ #249 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:kprobe_trace_self_tests_init+0x32d/0x36b Code: b7 e8 4f 8d a2 fe 85 c0 74 10 0f 0b 48 c7 c7 c8 1b 0d b7 ff c3 e8 19 af 99 fe 48 c7 c7 40 93 27 b7 e8 7f 1a a5 fe 85 c0 74 10 <0f> 0b 48 c7 c7 f8 1b 0d b7 ff c3 e8 f9 ae 9 a0 fe 85 RSP: 0018:ffffb36e40653e08 EFLAGS: 00010286 RAX: 00000000fffffff0 RBX: 0000000000000000 RCX: ffffb36e40653d5c RDX: 0000000000000000 RSI: ffffffffb72776e0 RDI: 0000000000000246 RBP: ffff98414fe58ff8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff98415d8aa940 R12: 0000000000000000 R13: ffffffffb737c1b0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff98415ea80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f959ce741b8 CR3: 000000011a210002 CR4: 00000000001606e0 Call Trace: ? init_kprobe_trace+0x19e/0x19e ? do_early_param+0x8e/0x8e do_one_initcall+0x6f/0x2b4 ? do_early_param+0x8e/0x8e kernel_init_freeable+0x21d/0x2c6 ? rest_init+0x146/0x146 kernel_init+0xa/0x10a ret_from_fork+0x3a/0x50 ---[ end trace 488430c083a4c956 ]--- As with the trace events, if a trace event is set on the kernel command line, the trace events start up tests are suspended. The kprobe start up tests should do the same when a kprobe is enabled on the kernel command line. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-24 02:50:34 +03:00
if (kprobe_boot_events_enabled) {
pr_info("Skipping kprobe tests due to kprobe_event on cmdline\n");
return 0;
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
target = kprobe_trace_selftest_target;
pr_info("Testing kprobe tracing: ");
ret = trace_run_command("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)",
create_or_delete_trace_kprobe);
if (WARN_ON_ONCE(ret)) {
pr_warn("error on probing function entry.\n");
warn++;
} else {
/* Enable trace point */
tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tk == NULL)) {
pr_warn("error on getting new probe.\n");
warn++;
} else {
file = find_trace_probe_file(tk, top_trace_array());
if (WARN_ON_ONCE(file == NULL)) {
pr_warn("error on getting probe file.\n");
warn++;
} else
enable_trace_kprobe(
trace_probe_event_call(&tk->tp), file);
}
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
ret = trace_run_command("r:testprobe2 kprobe_trace_selftest_target $retval",
create_or_delete_trace_kprobe);
if (WARN_ON_ONCE(ret)) {
pr_warn("error on probing function return.\n");
warn++;
} else {
/* Enable trace point */
tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tk == NULL)) {
pr_warn("error on getting 2nd new probe.\n");
warn++;
} else {
file = find_trace_probe_file(tk, top_trace_array());
if (WARN_ON_ONCE(file == NULL)) {
pr_warn("error on getting probe file.\n");
warn++;
} else
enable_trace_kprobe(
trace_probe_event_call(&tk->tp), file);
}
}
if (warn)
goto end;
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
ret = target(1, 2, 3, 4, 5, 6);
/*
* Not expecting an error here, the check is only to prevent the
* optimizer from removing the call to target() as otherwise there
* are no side-effects and the call is never performed.
*/
if (ret != 21)
warn++;
/* Disable trace points before removing it */
tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tk == NULL)) {
pr_warn("error on getting test probe.\n");
warn++;
} else {
if (trace_kprobe_nhit(tk) != 1) {
pr_warn("incorrect number of testprobe hits\n");
warn++;
}
file = find_trace_probe_file(tk, top_trace_array());
if (WARN_ON_ONCE(file == NULL)) {
pr_warn("error on getting probe file.\n");
warn++;
} else
disable_trace_kprobe(
trace_probe_event_call(&tk->tp), file);
}
tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tk == NULL)) {
pr_warn("error on getting 2nd test probe.\n");
warn++;
} else {
if (trace_kprobe_nhit(tk) != 1) {
pr_warn("incorrect number of testprobe2 hits\n");
warn++;
}
file = find_trace_probe_file(tk, top_trace_array());
if (WARN_ON_ONCE(file == NULL)) {
pr_warn("error on getting probe file.\n");
warn++;
} else
disable_trace_kprobe(
trace_probe_event_call(&tk->tp), file);
}
ret = trace_run_command("-:testprobe", create_or_delete_trace_kprobe);
if (WARN_ON_ONCE(ret)) {
pr_warn("error on deleting a probe.\n");
warn++;
}
ret = trace_run_command("-:testprobe2", create_or_delete_trace_kprobe);
if (WARN_ON_ONCE(ret)) {
pr_warn("error on deleting a probe.\n");
warn++;
}
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
end:
ret = dyn_events_release_all(&trace_kprobe_ops);
if (WARN_ON_ONCE(ret)) {
pr_warn("error on cleaning up probes.\n");
warn++;
}
/*
* Wait for the optimizer work to finish. Otherwise it might fiddle
* with probes in already freed __init text.
*/
wait_for_kprobe_optimizer();
if (warn)
pr_cont("NG: Some tests are failed. Please check them.\n");
else
pr_cont("OK\n");
tracing: Add kprobe-based event tracer Add kprobes-based event tracer on ftrace. This tracer is similar to the events tracer which is based on Tracepoint infrastructure. Instead of Tracepoint, this tracer is based on kprobes (kprobe and kretprobe). It probes anywhere where kprobes can probe(this means, all functions body except for __kprobes functions). Similar to the events tracer, this tracer doesn't need to be activated via current_tracer, instead of that, just set probe points via /sys/kernel/debug/tracing/kprobe_events. And you can set filters on each probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter. This tracer supports following probe arguments for each probe. %REG : Fetch register REG sN : Fetch Nth entry of stack (N >= 0) sa : Fetch stack address. @ADDR : Fetch memory at ADDR (ADDR should be in kernel) @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) aN : Fetch function argument. (N >= 0) rv : Fetch return value. ra : Fetch return address. +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address. See Documentation/trace/kprobetrace.txt in the next patch for details. Changes from v13: - Support 'sa' for stack address. - Use call->data instead of container_of() macro. [fweisbec@gmail.com: Fixed conflict against latest tracing/core] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-14 00:35:11 +04:00
return 0;
}
late_initcall(kprobe_trace_self_tests_init);
#endif