diff options
| author | Chun-Tse Shao <ctshao@google.com> | 2025-02-26 16:28:56 -0800 |
|---|---|---|
| committer | Namhyung Kim <namhyung@kernel.org> | 2025-02-28 10:09:02 -0800 |
| commit | 3c97e7b991974bd3cd84e9d9fe962e3d1ee071ab (patch) | |
| tree | 3ebc3b0d91ab7b536b804b6fbc337e33d51b6ff9 /tools/perf/Documentation | |
| parent | a40ccb7d98d566a14b6f9c6b3985f91db407306a (diff) | |
perf lock: Report owner stack in usermode
This patch parses `owner_lock_stat` into a RB tree, enabling ordered
reporting of owner lock statistics with stack traces. It also updates
the documentation for the `-o` option in contention mode, decouples `-o`
from `-t`, and issues a warning to inform users about the new behavior
of `-ov`.
Example output:
$ sudo ~/linux/tools/perf/perf lock con -abvo -Y mutex-spin -E3 perf bench sched pipe
...
contended total wait max wait avg wait type caller
171 1.55 ms 20.26 us 9.06 us mutex pipe_read+0x57
0xffffffffac6318e7 pipe_read+0x57
0xffffffffac623862 vfs_read+0x332
0xffffffffac62434b ksys_read+0xbb
0xfffffffface604b2 do_syscall_64+0x82
0xffffffffad00012f entry_SYSCALL_64_after_hwframe+0x76
36 193.71 us 15.27 us 5.38 us mutex pipe_write+0x50
0xffffffffac631ee0 pipe_write+0x50
0xffffffffac6241db vfs_write+0x3bb
0xffffffffac6244ab ksys_write+0xbb
0xfffffffface604b2 do_syscall_64+0x82
0xffffffffad00012f entry_SYSCALL_64_after_hwframe+0x76
4 51.22 us 16.47 us 12.80 us mutex do_epoll_wait+0x24d
0xffffffffac691f0d do_epoll_wait+0x24d
0xffffffffac69249b do_epoll_pwait.part.0+0xb
0xffffffffac693ba5 __x64_sys_epoll_pwait+0x95
0xfffffffface604b2 do_syscall_64+0x82
0xffffffffad00012f entry_SYSCALL_64_after_hwframe+0x76
=== owner stack trace ===
3 31.24 us 15.27 us 10.41 us mutex pipe_read+0x348
0xffffffffac631bd8 pipe_read+0x348
0xffffffffac623862 vfs_read+0x332
0xffffffffac62434b ksys_read+0xbb
0xfffffffface604b2 do_syscall_64+0x82
0xffffffffad00012f entry_SYSCALL_64_after_hwframe+0x76
...
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
Tested-by: Athira Rajeev <atrajeev@linux.ibm.com>
Link: https://lore.kernel.org/r/20250227003359.732948-5-ctshao@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'tools/perf/Documentation')
| -rw-r--r-- | tools/perf/Documentation/perf-lock.txt | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/tools/perf/Documentation/perf-lock.txt b/tools/perf/Documentation/perf-lock.txt index d3793054f7d3..859dc11a7372 100644 --- a/tools/perf/Documentation/perf-lock.txt +++ b/tools/perf/Documentation/perf-lock.txt @@ -179,8 +179,9 @@ CONTENTION OPTIONS -o:: --lock-owner:: - Show lock contention stat by owners. Implies --threads and - requires --use-bpf. + Show lock contention stat by owners. This option can be combined with -t, + which shows owner's per thread lock stats, or -v, which shows owner's + stacktrace. Requires --use-bpf. -Y:: --type-filter=<value>:: |