To avoid confusion caused by the increasing fragmentation of the BPF
Loader program, this commit would like to change to the libbpf loader
instead of using the bpf_load.
Thanks to libbpf's bpf_link interface, managing the tracepoint BPF
program is much easier. bpf_program__attach_tracepoint manages the
enable of tracepoint event and attach of BPF programs to it with a
single interface bpf_link, so there is no need to manage event_fd and
prog_fd separately.
This commit refactors xdp_monitor with using this libbpf API, and the
bpf_load is removed and migrated to libbpf.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201010181734.1109-2-danieltimlee@gmail.com
Memset on the pointer right after malloc can cause a NULL pointer
deference if it failed to allocate memory. A simple fix is to
replace malloc()/memset() pair with a simple call to calloc().
Fixes: 0fca931a6f ("samples/bpf: program demonstrating access to xdp_rxq_info")
Signed-off-by: Gaurav Singh <gaurav1086@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Update xdp_monitor to use the recently added err code introduced
in tracepoint xdp:xdp_devmap_xmit, to show if the drop count is
caused by some driver general delivery problem. Other kind of drops
will likely just be more normal TX space issues.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The xdp_monitor sample/tool is updated to use the new tracepoint
xdp:xdp_devmap_xmit the previous patch just introduced.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There are two files in the tree called libbpf.h which is becoming
problematic. Most samples don't actually need the local libbpf.h
they simply include it to get to bpf/bpf.h. Include bpf/bpf.h
directly instead.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The variable rec_i contains an XDP action code not an error.
Thus, using err2str() was wrong, it should have been action2str().
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The xdp_redirect_cpu sample have some "builtin" monitoring of the
tracepoints for xdp_cpumap_*, but it is practical to have an external
tool that can monitor these transpoint as an easy way to troubleshoot
an application using XDP + cpumap.
Specifically I need such external tool when working on Suricata and
XDP cpumap redirect. Extend the xdp_monitor tool sample with
monitoring of these xdp_cpumap_* tracepoints. Model the output format
like xdp_redirect_cpu.
Given I needed to handle per CPU decoding for cpumap, this patch also
add per CPU info on the existing monitor events. This resembles part
of the builtin monitoring output from sample xdp_rxq_info. Thus, also
covering part of that sample in an external monitoring tool.
Performance wise, the cpumap tracepoints uses bulking, which cause
them to have very little overhead. Thus, they are enabled by default.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Other concurrent running programs, like perf or the XDP program what
needed to be monitored, might take up part of the max locked memory
limit. Thus, the xdp_monitor tool have to set the RLIMIT_MEMLOCK to
RLIM_INFINITY, as it cannot determine a more sane limit.
Using the man exit(3) specified EXIT_FAILURE return exit code, and
correct other users too.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also monitor the tracepoint xdp_exception. This tracepoint is usually
invoked by the drivers. Programs themselves can activate this by
returning XDP_ABORTED, which will drop the packet but also trigger the
tracepoint. This is useful for distinguishing intentional (XDP_DROP)
vs. ebpf-program error cases that cased a drop (XDP_ABORTED).
Drivers also use this tracepoint for reporting on XDP actions that are
unknown to the specific driver. This can help the user to detect if a
driver e.g. doesn't implement XDP_REDIRECT yet.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make local functions static to fix
HOSTCC samples/bpf/xdp_monitor_user.o
samples/bpf/xdp_monitor_user.c:64:7: warning: no previous prototype for ‘gettime’ [-Wmissing-prototypes]
__u64 gettime(void)
^~~~~~~
samples/bpf/xdp_monitor_user.c:209:6: warning: no previous prototype for ‘print_bpf_prog_info’ [-Wmissing-prototypes]
void print_bpf_prog_info(void)
^~~~~~~~~~~~~~~~~~~
Fixes: 3ffab54602 ("samples/bpf: xdp_monitor tool based on tracepoints")
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This tool xdp_monitor demonstrate how to use the different xdp_redirect
tracepoints xdp_redirect{,_map}{,_err} from a BPF program.
The default mode is to only monitor the error counters, to avoid
affecting the per packet performance. Tracepoints comes with a base
overhead of 25 nanosec for an attached bpf_prog, and 48 nanosec for
using a full perf record (with non-matching filter). Thus, default
loading the --stats mode could affect the maximum performance.
This version of the tool is very simple and count all types of errors
as one. It will be natural to extend this later with the different
types of errors that can occur, which should help users quickly
identify common mistakes.
Because the TP_STRUCT was kept in sync all the tracepoints loads the
same BPF code. It would also be natural to extend the map version to
demonstrate how the map information could be used.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel T. Lee
Gaurav Singh
Jesper Dangaard Brouer
Jakub Kicinski
Prashant Bhole
Stephen Hemminger