On s390x perf test 1 failed. It turned out that commit 4a084ecfc8
("perf report: Fix module symbol adjustment for s390x") was incorrect.
The previous implementation in dso__load_sym() is also suitable for
s390x.
Therefore this patch undoes commit 4a084ecfc8.
Signed-off-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
Fixes: 4a084ecfc8 ("perf report: Fix module symbol adjustment for s390x")
LPU-Reference: 20170915071404.58398-1-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-5ani7ly57zji7s0hmzkx416l@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
On x86, the plt header size is as same as the plt entry size, and can be
identified from shdr's sh_entsize of the plt.
But we can't assume that the sh_entsize of the plt shdr is always the
plt entry size in all architecture, and the plt header size may be not
as same as the plt entry size in some architecure.
On ARM, the plt header size is 20 bytes and the plt entry size is 12
bytes (don't consider the FOUR_WORD_PLT case) that refer to the binutils
implementation. The plt section is as follows:
Disassembly of section .plt:
000004a0 <__cxa_finalize@plt-0x14>:
4a0: e52de004 push {lr} ; (str lr, [sp, #-4]!)
4a4: e59fe004 ldr lr, [pc, #4] ; 4b0 <_init+0x1c>
4a8: e08fe00e add lr, pc, lr
4ac: e5bef008 ldr pc, [lr, #8]!
4b0: 00008424 .word 0x00008424
000004b4 <__cxa_finalize@plt>:
4b4: e28fc600 add ip, pc, #0, 12
4b8: e28cca08 add ip, ip, #8, 20 ; 0x8000
4bc: e5bcf424 ldr pc, [ip, #1060]! ; 0x424
000004c0 <printf@plt>:
4c0: e28fc600 add ip, pc, #0, 12
4c4: e28cca08 add ip, ip, #8, 20 ; 0x8000
4c8: e5bcf41c ldr pc, [ip, #1052]! ; 0x41c
On AARCH64, the plt header size is 32 bytes and the plt entry size is 16
bytes. The plt section is as follows:
Disassembly of section .plt:
0000000000000560 <__cxa_finalize@plt-0x20>:
560: a9bf7bf0 stp x16, x30, [sp,#-16]!
564: 90000090 adrp x16, 10000 <__FRAME_END__+0xf8a8>
568: f944be11 ldr x17, [x16,#2424]
56c: 9125e210 add x16, x16, #0x978
570: d61f0220 br x17
574: d503201f nop
578: d503201f nop
57c: d503201f nop
0000000000000580 <__cxa_finalize@plt>:
580: 90000090 adrp x16, 10000 <__FRAME_END__+0xf8a8>
584: f944c211 ldr x17, [x16,#2432]
588: 91260210 add x16, x16, #0x980
58c: d61f0220 br x17
0000000000000590 <__gmon_start__@plt>:
590: 90000090 adrp x16, 10000 <__FRAME_END__+0xf8a8>
594: f944c611 ldr x17, [x16,#2440]
598: 91262210 add x16, x16, #0x988
59c: d61f0220 br x17
NOTES:
In addition to ARM and AARCH64, other architectures, such as
s390/alpha/mips/parisc/poperpc/sh/sparc/xtensa also need to consider
this issue.
Signed-off-by: Li Bin <huawei.libin@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: David Tolnay <dtolnay@gmail.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: zhangmengting@huawei.com
Link: http://lkml.kernel.org/r/1496622849-21877-1-git-send-email-huawei.libin@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'perf report' tool does not display the addresses of kernel module
symbols correctly.
For example symbol qeth_send_ipa_cmd in kernel module qeth.ko has this
relative address for function qeth_send_ipa_cmd():
[root@s8360047 linux]# nm -g drivers/s390/net/qeth.ko | fgrep send_ipa_cmd
0000000000013088 T qeth_send_ipa_cmd
The module is loaded at address:
[root@s8360047 linux]# cat /sys/module/qeth/sections/.text
0x000003ff80296d20
[root@s8360047 linux]#
This should result in a start address of:
0x13088 + 0x3ff80296d20 = 0x3ff802a9da8
Using crash to verify the address on a live system:
[root@s8360046 linux]# crash vmlinux
crash 7.1.9++
Copyright (C) 2002-2016 Red Hat, Inc.
Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation
[...]
crash> mod -s qeth drivers/s390/net/qeth.ko
MODULE NAME SIZE OBJECT FILE
3ff8028d700 qeth 151552 drivers/s390/net/qeth.ko
crash> sym qeth_send_ipa_cmd
3ff802a9da8 (T) qeth_send_ipa_cmd [qeth] /root/linux/drivers/s390/net/qeth_core_main.c: 2944
crash>
Now perf report displays the address of symbol qeth_send_ipa_cmd:
symbol__new:
qeth_send_ipa_cmd 0x130f0-0x132ce
There is a difference of 0x68 between the entry in the symbol table (see
nm command above) and perf. The difference is from the offset the .text
segment of qeth.ko:
[root@s8360047 perf]# readelf -a drivers/s390/net/qeth.ko
Section Headers:
[Nr] Name Type Address Offset
Size EntSize Flags Link Info Align
[ 0] NULL 0000000000000000 00000000
0000000000000000 0000000000000000 0 0 0
[ 1] .note.gnu.build-i NOTE 0000000000000000 00000040
0000000000000024 0000000000000000 A 0 0 4
[ 2] .text PROGBITS 0000000000000000 00000068
000000000001c8a0 0000000000000000 AX 0 0 8
As seen the .text segment has an offset of 0x68 with start address 0x0.
Therefore 0x68 is added to the address of qeth_send_ipa_cmd and thus
0x13088 + 0x68 = 0x130f0 is displayed.
This is wrong, perf report needs to display the start address of symbol
qeth_send_ipa_cmd at 0x13088 + qeth.ko.text section start address.
The qeth.ko module .text start address is available in the qeth.ko DSO
map. Just identify the kernel module symbols and correct the addresses.
With the fix I see this correct address for symbol: symbol__new:
qeth_send_ipa_cmd 0x3ff802a9da8-0x3ff802a9f86
Signed-off-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
LPU-Reference: 20170803134902.47207-1-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-q8lktlpoxb5e3dj52u1s1rw4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
During work on perf report for s390 I ran into the following issue:
0 0x318 [0x78]: PERF_RECORD_MMAP -1/0:
[0x3ff804d6990(0xfffffc007fb2966f) @ 0]:
x /lib/modules/4.12.0perf1+/kernel/drivers/s390/net/qeth_l2.ko
This is a PERF_RECORD_MMAP entry of the perf.data file with an invalid
module size for qeth_l2.ko (the s390 ethernet device driver).
Even a mainframe does not have 0xfffffc007fb2966f bytes of main memory.
It turned out that this wrong size is created by the perf record
command. What happens is this function call sequence from
__cmd_record():
perf_session__new():
perf_session__create_kernel_maps():
machine__create_kernel_maps():
machine__create_modules(): Creates map for all loaded kernel modules.
modules__parse(): Reads /proc/modules and extracts module name and
load address (1st and last column)
machine__create_module(): Called for every module found in /proc/modules.
Creates a new map for every module found and enters
module name and start address into the map. Since the
module end address is unknown it is set to zero.
This ends up with a kernel module map list sorted by module start
addresses. All module end addresses are zero.
Last machine__create_kernel_maps() calls function map_groups__fixup_end().
This function iterates through the maps and assigns each map entry's
end address the successor map entry start address. The last entry of the
map group has no successor, so ~0 is used as end to consume the remaining
memory.
Later __cmd_record calls function record__synthesize() which in turn calls
perf_event__synthesize_kernel_mmap() and perf_event__synthesize_modules()
to create PERF_REPORT_MMAP entries into the perf.data file.
On s390 this results in the last module qeth_l2.ko
(which has highest start address, see module table:
[root@s8360047 perf]# cat /proc/modules
qeth_l2 86016 1 - Live 0x000003ff804d6000
qeth 266240 1 qeth_l2, Live 0x000003ff80296000
ccwgroup 24576 1 qeth, Live 0x000003ff80218000
vmur 36864 0 - Live 0x000003ff80182000
qdio 143360 2 qeth_l2,qeth, Live 0x000003ff80002000
[root@s8360047 perf]# )
to be the last entry and its map has an end address of ~0.
When the PERF_RECORD_MMAP entry is created for kernel module qeth_l2.ko
its start address and length is written. The length is calculated in line:
event->mmap.len = pos->end - pos->start;
and results in 0xffffffffffffffff - 0x3ff804d6990(*) = 0xfffffc007fb2966f
(*) On s390 the module start address is actually determined by a __weak function
named arch__fix_module_text_start() in machine__create_module().
I think this improvable. We can use the module size (2nd column of /proc/modules)
to get each loaded kernel module size and calculate its end address.
Only for map entries which do not have a valid end address (end is still zero)
we can use the heuristic we have now, that is use successor start address or ~0.
Signed-off-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
LPU-Reference: 20170803134902.47207-2-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-nmoqij5b5vxx7rq2ckwu8iaj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The input string is not modified and thus can be passed in as a pointer
to const data.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170806212446.24925-3-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The symsrc__init() overwrites dso->symtab_type as symsrc->type in
dso__load_sym(). But for compressed kernel modules in the build-id
cache, it should have original symtab type to be decompressed as needed.
This fixes perf annotate to show disassembly of the function properly.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170608073109.30699-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move decompress_kmodule() to util/dso.c and split it into two functions
returning fd and (decompressed) file path. The existing user only wants
the fd version but the path version will be used soon.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170608073109.30699-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The decompress_kmodule() decompresses kernel modules in order to load
symbols from it. In the DSO_BINARY_TYPE__BUILD_ID_CACHE case, it needs
the full file path to extract the file extension to determine the
decompression method. But overwriting 'name' will fail the
decompression since it might point to a non-existing old file.
Instead, use dso->long_name for having the correct extension and use the
real filename to decompress.
In the DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP case, both names should
be the same. This allows resolving symbols in the old modules.
Before:
$ perf report -i perf.data.old | grep scsi_mod
0.00% cc1 [scsi_mod] [k] 0x0000000000004aa6
0.00% as [scsi_mod] [k] 0x00000000000099e1
0.00% cc1 [scsi_mod] [k] 0x0000000000009830
0.00% cc1 [scsi_mod] [k] 0x0000000000001b8f
After:
0.00% cc1 [scsi_mod] [k] scsi_handle_queue_ramp_up
0.00% as [scsi_mod] [k] scsi_sg_alloc
0.00% cc1 [scsi_mod] [k] scsi_setup_cmnd
0.00% cc1 [scsi_mod] [k] scsi_get_command
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170531120105.21731-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
More stuff that came from git, out of the hodge-podge that is util.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-e3lana4gctz3ub4hn4y29hkw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It would be useful for perf to support a mode to query the inline stack
for a given callgraph address. This would simplify finding the right
code in code that does a lot of inlining.
The srcline.c has contained the code which supports to translate the
address to filename:line_nr. This patch just extends the function to let
it support getting the inline stacks.
It introduces the inline_list which will store the inline function
result (filename:line_nr and funcname).
If BFD lib is not supported, the result is only filename:line_nr.
Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-3-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
During a "perf buildid-cache --add" command, the section ".note.stapsdt"
of the "added" binary is scanned in order to list the available SDT
markers available in a binary. The parts containing the probes arguments
were left unscanned.
The whole section is now parsed; the probe arguments are extracted for
later use.
Signed-off-by: Alexis Berlemont <alexis.berlemont@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20161214000732.1710-2-alexis.berlemont@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It now can have negative value to suppress the message entirely. So it
needs to check it being positive.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170217081742.17417-3-namhyung@kernel.org
[ Adjust fuzz on tools/perf/util/pmu.c, add > 0 checks in many other places ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Markus reported that perf segfaults when reading /sys/kernel/notes from
a kernel linked with GNU gold, due to what looks like a gold bug, so do
some bounds checking to avoid crashing in that case.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Report-Link: http://lkml.kernel.org/r/20161219161821.GA294@x4
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ryhgs6a6jxvz207j2636w31c@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We're not using it anymore, few users were, but we really could do
without it, simplify lots of functions by removing it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-1zng8wdznn00iiz08bb7q3vn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This was being done just in 'perf top', but grouping idle symbols should
be useful in other places as well, so remove one more symbol_filter_t
user by moving this to the symbol library.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-5r7xitjkzjr9jak1zy3d8u5l@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When we call symbol__fixup_duplicate() we use algorithms to pick the
"best" symbols for cases where there are various functions/aliases to an
address, and those check zero size symbols, which, before calling
symbol__fixup_end() are _all_ symbols in a just parsed kallsyms file.
So first fixup the end, then fixup the duplicates.
Found while trying to figure out why 'perf test vmlinux' failed, see the
output of 'perf test -v vmlinux' to see cases where the symbols picked
as best for vmlinux don't match the ones picked for kallsyms.
Cc: Anton Blanchard <anton@samba.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 694bf407b0 ("perf symbols: Add some heuristics for choosing the best duplicate symbol")
Link: http://lkml.kernel.org/n/tip-rxqvdgr0mqjdxee0kf8i2ufn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We can allow aliases to be kept, but we were checking this just when
loading vmlinux files, be consistent, do it for any symbol table loading
code that calls symbol__fixup_duplicate() by making this function check
.allow_aliases instead.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 680d926a8c ("perf symbols: Allow symbol alias when loading map for symbol name")
Link: http://lkml.kernel.org/n/tip-z0avp0s6cfjckc4xj3pdfjdz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ignore the buildid of running kernel when both of --definition and
--vmlinux is given because that kernel should be off-line.
This also skips post-processing of kprobe event for relocating symbol
and checking blacklist, because it can not be done on off-line kernel.
E.g. without this fix perf shows an error as below
----
$ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
./vmlinux-arm with build id 7a1f76dd56e9c4da707cd3d6333f50748141434b not found, continuing without symbols
Failed to find symbol do_sys_open in kernel
Error: Failed to add events.
----
with this fix, we can get the definition
----
$ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
p:probe/do_sys_open do_sys_open+0
----
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214228193.23638.12581984840822162131.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The symbols in the synthesized @plt entries where not demangled before,
i.e. we could end up with entries such as:
$ perf report
Samples: 7K of event 'cycles:ppp', Event count (approx.): 6223833141
Children Self Command Shared Object Symbol
- 93.63% 28.89% lab_mandelbrot lab_mandelbrot [.] main
- 73.81% main
- 33.57% hypot
27.76% __hypot_finite
15.97% __muldc3
2.90% __muldc3@plt
2.40% _ZNK6QImage6heightEv@plt
+ 2.14% QColor::rgb
1.94% _ZNK6QImage5widthEv@plt
1.92% cabs@plt
This patch remedies this issue by also applying demangling to the
synthesized symbols. The output for the above is now:
$ perf report
Samples: 7K of event 'cycles:ppp', Event count (approx.): 6223833141
Children Self Command Shared Object Symbol
- 93.63% 28.89% lab_mandelbrot lab_mandelbrot [.] main
- 73.81% main
- 33.57% hypot
27.76% __hypot_finite
15.97% __muldc3
2.90% __muldc3@plt
2.40% QImage::height() const@plt
+ 2.14% QColor::rgb
1.94% QImage::width() const@plt
1.92% cabs@plt
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
LPU-Reference: 20160830114102.30863-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 73cdf0c6ea ("perf symbols: Record text offset in dso
to calculate objdump address") started storing the offset of
the text section for all DSOs:
if (elf_section_by_name(elf, &ehdr, &tshdr, ".text", NULL))
dso->text_offset = tshdr.sh_addr - tshdr.sh_offset;
Unfortunately this breaks debuginfo files, because we need to calculate
the offset of the text section in the associated executable file. As a
result perf annotate returns junk for all debuginfo files.
Fix this by using runtime_ss->elf which should point at the executable
when parsing a debuginfo file.
Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v4.6+
Fixes: 73cdf0c6ea ("perf symbols: Record text offset in dso to calculate objdump address")
Link: http://lkml.kernel.org/r/20160813115533.6de17912@kryten
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That is not present on some libelf implementations, such as the one used
in Alpine Linux: libelf-0.8.13.
This ends up disabling the SDT code, that relies on this function.
One alternative would be to provide an weak fallback implementation or
the open coded variant used by the buildid sysfs notes reading code.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-82lh22ybedy9b9lych8xj12g@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This one can be safely defined to be Elf64_Nhdr, as it is in elfutils's
libelf, but not on musl libc, as both Elf64_Nhdr and Elf32_Nhdr have
the same layout.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-w8z8614l03lc8bip4ijbywbt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch serves the initial support to identify and list SDT events in
binaries. When programs containing SDT markers are compiled, gcc with
the help of assembler directives identifies them and places them in the
section ".note.stapsdt".
To find these markers from the binaries, one needs to traverse through
this section and parse the relevant details like the name, type and
location of the marker. Also, the original location could be skewed due
to the effect of prelinking. If that is the case, the locations need to
be adjusted.
The functions in this patch open a given ELF, find out the SDT section,
parse the relevant details, adjust the location (if necessary) and
populate them in a list.
A typical note entry in ".note.stapsdt" section is as follows :
|--nhdr.n_namesz--|
------------------------------------
| nhdr | "stapsdt" |
----- |----------------------------------|
| | <location> <base_address> |
| | <semaphore> |
nhdr.n_descsize | "provider_name" "note_name" |
| | <args> |
----- |----------------------------------|
| nhdr | "stapsdt" |
|...
The above shows an excerpt from the section ".note.stapsdt". 'nhdr' is
a structure which has the note name size (n_namesz), note description
size (n_desc_sz) and note type (n_type).
So, in order to parse the note note info, we need nhdr to tell us where
to start from. As can be seen from <sys/sdt.h>, the name of the SDT
notes given is "stapsdt". But this is not the identifier of the note.
After that, we go to description of the note to find out its location, the
address of the ".stapsdt.base" section and the semaphore address.
Then, we find the provider name and the SDT marker name and then follow the
arguments.
Signed-off-by: Hemant Kumar <hemant@linux.vnet.ibm.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146736022628.27797.1201368329092908163.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That appeared after 0.140, and will be used in the SDT code, so, to
avoid bisection break on older systems, add a feature detection and
provide a stub with a pr_debug() to keep it building.
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-80y0eldgweorqnwha9rvfxjr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
ppc64le functions have a Global Entry Point (GEP) and a Local Entry
Point (LEP). While placing a probe, we always prefer the LEP since it
catches function calls through both the GEP and the LEP. In order to do
this, we fixup the function entry points during elf symbol table lookup
to point to the LEPs. This works, but breaks 'perf test kallsyms' since
the symbols loaded from the symbol table (pointing to the LEP) do not
match the symbols in kallsyms.
To fix this, we do not adjust all the symbols during symbol table load.
Instead, we note down st_other in a newly introduced arch-specific
member of perf symbol structure, and later use this to adjust the probe
trace point.
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/6be7c2b17e370100c2f79dd444509df7929bdd3e.1460451721.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
He Kuang reported a problem that perf fails to get correct symbol on
Android platform in [1]. The problem can be reproduced on normal x86_64
platform. I will describe the reproducing steps in detail at the end of
commit message.
The reason of this problem is the missing of symbol adjustment for normal
shared objects. In most of the cases skipping adjustment is okay. However,
when '.text' section have different 'address' and 'offset' the result is wrong.
I checked all shared objects in my working platform, only wine dll objects and
debug objects (in .debug) have this problem. However, it is common on Android.
For example:
$ readelf -S ./libsurfaceflinger.so | grep \.text
[10] .text PROGBITS 0000000000029030 00012030
This patch enables symbol adjustment for dynamic objects so the symbol
address got from elfutils would be adjusted correctly.
Now nearly all types of ELF files should adjust symbols. Makes
ss->adjust_symbols default to true.
Steps to reproduce the problem:
$ cat ./Makefile
PWD := $(shell pwd)
LDFLAGS += "-Wl,-rpath=$(PWD)"
CFLAGS += -g
main: main.c libbuggy.so
libbuggy.so: buggy.c
gcc -g -shared -fPIC -Wl,-Ttext-segment=0x200000 $< -o $@
clean:
rm -rf main libbuggy.so *.o
$ cat ./buggy.c
int fib(int x)
{
return (x == 0) ? 1 : (x == 1) ? 1 : fib(x - 1) + fib(x - 2);
}
$ cat ./main.c
#include <stdio.h>
extern int fib(int x);
int main()
{
int i;
for (i = 0; i < 40; i++)
printf("%d\n", fib(i));
return 0;
}
$ make
$ perf record ./main
...
$ perf report --stdio
# Overhead Command Shared Object Symbol
# ........ ....... ................. ...............................
#
14.97% main libbuggy.so [.] 0x000000000000066c
8.68% main libbuggy.so [.] 0x00000000000006aa
8.52% main libbuggy.so [.] fib@plt
7.95% main libbuggy.so [.] 0x0000000000000664
5.94% main libbuggy.so [.] 0x00000000000006a9
5.35% main libbuggy.so [.] 0x0000000000000678
...
The correct result should be (after this patch):
# Overhead Command Shared Object Symbol
# ........ ....... ................. ...............................
#
91.47% main libbuggy.so [.] fib
8.52% main libbuggy.so [.] fib@plt
0.00% main [kernel.kallsyms] [k] kmem_cache_free
[1] http://lkml.kernel.org/g/1452567507-54013-1-git-send-email-hekuang@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kirill Smelkov <kirr@nexedi.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1460024671-64774-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Store DSO's .text offset into DSO, used for VDSOs and will also be used for
other needs, like handling kernel modules.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Cody P Schafer <dev@codyps.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kirill Smelkov <kirr@nexedi.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456479154-136027-2-git-send-email-wangnan0@huawei.com
[ Extracted from larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add Java function descriptor demangling support. Something bfd cannot
do.
Use the JAVA_DEMANGLE_NORET flag to avoid decoding the return type of
functions.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Carl Love <cel@us.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John McCutchan <johnmccutchan@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sonny Rao <sonnyrao@chromium.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1448874143-7269-2-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix dso__load_sym to put dso because dsos__add already got it.
Refcnt debugger explain the problem:
----
==== [0] ====
Unreclaimed dso: 0x19dd200
Refcount +1 => 1 at
./perf(dso__new+0x1ff) [0x4a62df]
./perf(dso__load_sym+0xe89) [0x503509]
./perf(dso__load_vmlinux+0xbf) [0x4aa77f]
./perf(dso__load_vmlinux_path+0x8c) [0x4aa8dc]
./perf() [0x50539a]
./perf(convert_perf_probe_events+0xd79) [0x50ad39]
./perf() [0x45600f]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f74dd0efaf5]
./perf() [0x4220a9]
Refcount +1 => 2 at
./perf(dso__get+0x34) [0x4a65f4]
./perf(map__new2+0x76) [0x4be216]
./perf(dso__load_sym+0xee1) [0x503561]
./perf(dso__load_vmlinux+0xbf) [0x4aa77f]
./perf(dso__load_vmlinux_path+0x8c) [0x4aa8dc]
./perf() [0x50539a]
./perf(convert_perf_probe_events+0xd79) [0x50ad39]
./perf() [0x45600f]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f74dd0efaf5]
./perf() [0x4220a9]
Refcount +1 => 3 at
./perf(dsos__add+0xf3) [0x4a6bc3]
./perf(dso__load_sym+0xfc1) [0x503641]
./perf(dso__load_vmlinux+0xbf) [0x4aa77f]
./perf(dso__load_vmlinux_path+0x8c) [0x4aa8dc]
./perf() [0x50539a]
./perf(convert_perf_probe_events+0xd79) [0x50ad39]
./perf() [0x45600f]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f74dd0efaf5]
./perf() [0x4220a9]
Refcount -1 => 2 at
./perf(dso__put+0x2f) [0x4a664f]
./perf(map_groups__exit+0xb9) [0x4bee29]
./perf(machine__delete+0xb0) [0x4b93d0]
./perf(exit_probe_symbol_maps+0x28) [0x506718]
./perf() [0x45628a]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f74dd0efaf5]
./perf() [0x4220a9]
Refcount -1 => 1 at
./perf(dso__put+0x2f) [0x4a664f]
./perf(machine__delete+0xfe) [0x4b941e]
./perf(exit_probe_symbol_maps+0x28) [0x506718]
./perf() [0x45628a]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f74dd0efaf5]
./perf() [0x4220a9]
----
So, in the dso__load_sym, dso is gotten 3 times, by dso__new,
map__new2, and dsos__add. The last 2 is actually released by
map_groups and machine__delete correspondingly. However, the
first reference by dso__new, is never released.
Committer note:
Changed the place where the reference count is dropped to:
Fix it by dropping it right after creating curr_map, since we know that
either that operation failed and we need to drop the dso refcount or
that it succeed and we have it referenced via curr_map->dso.
Then only drop the curr_map refcount after we call dsos__add() to make
sure we hold a reference to it via curr_map->dso.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20151209021118.10245.49869.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix dso__load_sym to put the map object which is already
insterted to kmaps.
Refcnt debugger shows
==== [0] ====
Unreclaimed map: 0x39113e0
Refcount +1 => 1 at
./perf(map__new2+0xb5) [0x4be155]
./perf(dso__load_sym+0xee1) [0x503461]
./perf(dso__load_vmlinux+0xbf) [0x4aa6df]
./perf(dso__load_vmlinux_path+0x8c) [0x4aa83c]
./perf() [0x50528a]
./perf(convert_perf_probe_events+0xd79) [0x50ac29]
./perf() [0x45600f]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f152368baf5]
./perf() [0x4220a9]
Refcount +1 => 2 at
./perf(maps__insert+0x9a) [0x4bfffa]
./perf(dso__load_sym+0xf89) [0x503509]
./perf(dso__load_vmlinux+0xbf) [0x4aa6df]
./perf(dso__load_vmlinux_path+0x8c) [0x4aa83c]
./perf() [0x50528a]
./perf(convert_perf_probe_events+0xd79) [0x50ac29]
./perf() [0x45600f]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f152368baf5]
./perf() [0x4220a9]
Refcount -1 => 1 at
./perf(map_groups__exit+0x94) [0x4bed04]
./perf(machine__delete+0xb0) [0x4b9300]
./perf(exit_probe_symbol_maps+0x28) [0x506608]
./perf() [0x45628a]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f152368baf5]
./perf() [0x4220a9]
This means that the dso__load_sym calls map__new2 and maps_insert, both
of them bump the map refcount, but map_groups__exit will drop just one
reference.
Fix it by dropping the refcount after inserting it into kmaps.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20151118064026.30709.50038.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A copy of /proc/kcore containing the kernel text can be made to the
buildid cache. e.g.
perf buildid-cache -v -k /proc/kcore
To workaround objdump limitations, a copy is also made when annotating
against /proc/kcore.
The copying process stops working from libelf about v1.62 onwards (the
problem was found with v1.63).
The cause is that a call to gelf_getphdr() in kcore__add_phdr() fails
because additional validation has been added to gelf_getphdr().
The use of gelf_getphdr() is a misguided attempt to get default
initialization of the Gelf_Phdr structure. That should not be
necessary because every member of the Gelf_Phdr structure is
subsequently assigned. So just remove the call to gelf_getphdr().
Similarly, a call to gelf_getehdr() in gelf_kcore__init() can be
removed also.
Committer notes:
Note to stable@kernel.org, from Adrian in the cover letter for this
patchkit:
The "Fix copying of /proc/kcore" problem goes back to v3.13 if you think
it is important enough for stable.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1443089122-19082-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This reverts commit f785f23576.
We have a test to check if elf_getphdrnum() is present, so, if it fails,
we'll get:
[acme@rhel5 linux]$ cat /tmp/build/perf/feature/test-libelf-getphdrnum.make.output
cc1: warnings being treated as errors
test-libelf-getphdrnum.c: In function ‘main’:
test-libelf-getphdrnum.c:7: warning: implicit declaration of function ‘elf_getphdrnum’
[acme@rhel5 linux]$
And this block will not be compiled:
#ifndef HAVE_ELF_GETPHDRNUM_SUPPORT
static int elf_getphdrnum(Elf *elf, size_t *dst)
...
#endif
So, if elf_getphdrnum() is being defined somewhere, there is a problem
with the test that is not detecting that function, go fix it.
Reported-by: Vinson Lee <vlee@twopensource.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-qn459fal6acvcvm50i8zxx9k@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Older kernels attempt to prelink vdso to its virtual address. To permit
annotation using objdump, the map__rip_2objdump() calculation must
result in that same address which we can infer from the start and offset
of the text section.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1439556606-11297-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When HAVE_ELF_GETPHDRNUM_SUPPORT is false we trip on this problem:
CC /tmp/build/perf/util/symbol-elf.o
util/symbol-elf.c:41:12: error: static declaration of ‘elf_getphdrnum’ follows non-static declaration
static int elf_getphdrnum(Elf *elf, size_t *dst)
^
In file included from util/symbol.h:19:0,
from util/symbol-elf.c:8:
/usr/include/libelf.h:206:12: note: previous declaration of ‘elf_getphdrnum’ was here
extern int elf_getphdrnum (Elf *__elf, size_t *__dst);
^
MKDIR /tmp/build/perf/bench/
/home/git/linux/tools/build/Makefile.build:68: recipe for target '/tmp/build/perf/util/symbol-elf.o' failed
make[3]: *** [/tmp/build/perf/util/symbol-elf.o] Error 1
Fix it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-qcmekyfedmov4sxr0wahcikr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This has a different model than the 'thread' and 'map' struct lifetimes:
there is not a definitive "don't use this DSO anymore" event, i.e. we may
get many 'struct map' holding references to the '/usr/lib64/libc-2.20.so'
DSO but then at some point some DSO may have no references but we still
don't want to straight away release its resources, because "soon" we may
get a new 'struct map' that needs it and we want to reuse its symtab or
other resources.
So we need some way to garbage collect it when crossing some memory
usage threshold, which is left for anoter patch, for now it is
sufficient to release it when calling dsos__exit(), i.e. when deleting
the whole list as part of deleting the 'struct machine' containing it,
which will leave only referenced objects being used.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-majzgz07cm90t2tejrjy4clf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We can, given a DSO, figure out if it is a kernel, a kernel module or
a userlevel DSO, so stop having to process two lists in several
functions.
If searching becomes an issue at some point, we can have them in a
rbtree, etc.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-s4yb0onpdywu6dj2xl9lxi4t@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have pointers to struct map instances in several places, like in the
hist_entry instances, so we need a way to know when we can destroy them,
otherwise we may either keep leaking them or end up referencing deleted
instances.
Start fixing it by reference counting them.
This patch puts the reference count for struct map in place, replacing
direct map__delete() calls with map__put() ones and then grabbing a
reference count when adding it to the maps struct where maps for a
struct thread are kept.
Next we'll grab reference counts when setting pointers to struct map
instances, in places like in the hist_entry code.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-wi19xczk0t2a41r1i2chuio5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
ppc64 ELF ABIv2 has a Global Entry Point (GEP) and a Local Entry Point
(LEP). For purposes of probing, we need the LEP - the offset to which is
encoded in st_other.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/ab9cc5e2b9de4cbaaf50f6ef2346a6a81100bad1.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If using the symbol table, symbol addresses are not being fixed up
properly, resulting in probes being placed at wrong addresses:
# perf probe do_fork
Added new event:
probe:do_fork (on do_fork)
You can now use it in all perf tools, such as:
perf record -e probe:do_fork -aR sleep 1
# cat /sys/kernel/debug/tracing/kprobe_events
p:probe/do_fork _text+635952
# printf "%x" 635952
9b430
# grep do_fork /boot/System.map
c0000000000ab430 T .do_fork
Fix by checking for ELF type ET_DYN used by ppc64 kernels.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/41392bb856ef62d929995e0b61967689b7915207.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch add checks in places where map__kmap is used to get kmaps
from struct kmap.
Error messages are added at map__kmap to warn invalid accessing of kmap
(for the case of !map->dso->kernel, kmap(map) does not exists at all).
Also, introduces map__kmaps() to warn uninitialized kmaps.
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1428394966-131044-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before, when some problem happened while trying to load the kernel
symtab, 'perf top' would show:
┌─Warning:───────────────────────────┐
│The vmlinux file can't be used. │
│Kernel samples will not be resolved.│
│ │
│ │
│Press any key... │
└────────────────────────────────────┘
Now, it reports:
# perf top --vmlinux /dev/null
┌─Warning:───────────────────────────────────────────┐
│The /tmp/passwd file can't be used: Invalid ELF file│
│Kernel samples will not be resolved. │
│ │
│ │
│Press any key... │
└────────────────────────────────────────────────────┘
This is possible because we now register the reason for not being able
to load the symtab in the dso->load_errno member, and provide a
dso__strerror_load() routine to format this error into a strerror like
string with a short reason for the error while loading.
That can be just forwarding the dso__strerror_load() call to
strerror_r(), or, for a separate errno range providing a custom message.
Reported-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-u5rb5uq63xqhkfb8uv2lxd5u@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When perf probe tries to add a probe in a binary using symbol name, it
sometimes failed since some symbols were discard during loading dso.
When it resolves an address to symbol, it'd be better to have just one
symbol at given address. But for finding address from symbol, it'd be
better to keep all names (including aliases).
So allow tools to state that they want to allow aliases via
symbol_conf.allow_aliases.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073127.6904.3232.stgit@localhost.localdomain
[ Original patch passwd allow_alias to many functions, use symbol_conf.allow_aliases instead ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4886f2ca19 added an arm-64 check, but the EM_AARCH64 macro is not
defined in older releases (e.g., RHEL6). Define if it is not defined.
Signed-off-by: David Ahern <david.ahern@oracle.com>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Link: http://lkml.kernel.org/r/1424306017-96797-1-git-send-email-david.ahern@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The token STT_GNU_IFUNC is not available with glibc 2.9 and older.
Define this token if it is not already defined.
This patch fixes this build errors with older versions of glibc.
CC util/symbol-elf.o
util/symbol-elf.c: In function ‘elf_sym__is_function’:
util/symbol-elf.c:75: error: ‘STT_GNU_IFUNC’ undeclared (first use in this function)
util/symbol-elf.c:75: error: (Each undeclared identifier is reported only once
util/symbol-elf.c:75: error: for each function it appears in.)
make: *** [util/symbol-elf.o] Error 1
Signed-off-by: Vinson Lee <vlee@twitter.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Avi Kivity <avi@cloudius-systems.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Waiman Long <Waiman.Long@hp.com>
Cc: stable@vger.kernel.org # 3.17+
Link: http://lkml.kernel.org/r/1423528286-13630-1-git-send-email-vlee@twopensource.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Aarch64 ELF files use mapping symbols with special names $x, $d
to identify regions of Aarch64 code (see Aarch64 ELF ABI - "ARM
IHI 0056B", section "4.5.4 Mapping symbols").
The patch filters out these symbols at load time, similar to
"696b97a perf symbols: Ignore mapping symbols on ARM" changes
done for ARM before V8.
Also added handling of mapping symbols that has format
"$d.<any>" and similar for both cases.
Note we are not making difference between EM_ARM and
EM_AARCH64 mapping symbols instead code handles superset
of both.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Avi Kivity <avi@cloudius-systems.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/1422340442-4673-2-git-send-email-victor.kamensky@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The commit c00c48fc6e ("perf symbols: Preparation for compressed
kernel module support") added support for compressed kernel modules but
it only supports system path DSOs. When a dso is read from build-id
cache, its filename doesn't end with ".gz" but has build-id. In this
case, we should fallback to the original dso->name.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1422518843-25818-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Thomas Richter
Li Bin
Milian Wolff
Namhyung Kim
Arnaldo Carvalho de Melo
Jin Yao
Alexis Berlemont
Masami Hiramatsu
Anton Blanchard
David Tolnay
Hemant Kumar
Naveen N. Rao
Wang Nan
Stephane Eranian
Masami Hiramatsu
Adrian Hunter
Ananth N Mavinakayanahalli
Jiri Olsa
David Ahern
Vinson Lee
Victor Kamensky