Commit Graph

4 Commits

Author SHA1 Message Date
Björn Töpel
e55190f26f samples/bpf: Fix build for task_fd_query_user.c
Add missing include for <linux/perf_event.h> which was removed from
perf-sys.h in commit 91854f9a07 ("perf tools: Move everything
related to sys_perf_event_open() to perf-sys.h").

Fixes: 91854f9a07 ("perf tools: Move everything related to sys_perf_event_open() to perf-sys.h")
Reported-by: KP Singh <kpsingh@google.com>
Reported-by: Florent Revest <revest@google.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: KP Singh <kpsingh@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191001112249.27341-1-bjorn.topel@gmail.com
2019-10-03 16:27:03 +02:00
Matteo Croce
a195cefff4 samples, bpf: suppress compiler warning
GCC 9 fails to calculate the size of local constant strings and produces a
false positive:

samples/bpf/task_fd_query_user.c: In function ‘test_debug_fs_uprobe’:
samples/bpf/task_fd_query_user.c:242:67: warning: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size 215 [-Wformat-truncation=]
  242 |  snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id",
      |                                                                   ^~
  243 |    event_type, event_alias);
      |                ~~~~~~~~~~~
samples/bpf/task_fd_query_user.c:242:2: note: ‘snprintf’ output between 45 and 300 bytes into a destination of size 256
  242 |  snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id",
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  243 |    event_type, event_alias);
      |    ~~~~~~~~~~~~~~~~~~~~~~~~

Workaround this by lowering the buffer size to a reasonable value.
Related GCC Bugzilla: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83431

Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-05-21 16:55:20 +02:00
Daniel T. Lee
d2e614cb07 samples: bpf: fix: broken sample regarding removed function
Currently, running sample "task_fd_query" and "tracex3" occurs the
following error. On kernel v5.0-rc* this sample will be unavailable
due to the removal of function 'blk_start_request' at commit "a1ce35f".
(function removed, as "Single Queue IO scheduler" no longer exists)

$ sudo ./task_fd_query
failed to create kprobe 'blk_start_request' error 'No such file or
directory'

This commit will change the function 'blk_start_request' to
'blk_mq_start_request' to fix the broken sample.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-27 17:27:22 +01:00
Yonghong Song
ecb96f7fe1 samples/bpf: add a samples/bpf test for BPF_TASK_FD_QUERY
This is mostly to test kprobe/uprobe which needs kernel headers.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24 18:18:20 -07:00