From: Chun-Tse Shao <ctshao@google.com>
To: linux-kernel@vger.kernel.org
Cc: Chun-Tse Shao <ctshao@google.com>,
peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
namhyung@kernel.org, mark.rutland@arm.com,
alexander.shishkin@linux.intel.com, jolsa@kernel.org,
irogers@google.com, adrian.hunter@intel.com,
kan.liang@linux.intel.com, nick.forrington@arm.com,
linux-perf-users@vger.kernel.org, bpf@vger.kernel.org
Subject: [PATCH v8 0/4] Tracing contention lock owner call stack
Date: Wed, 26 Feb 2025 16:28:52 -0800 [thread overview]
Message-ID: <20250227003359.732948-1-ctshao@google.com> (raw)
For perf lock contention, the current owner tracking (-o option) only
works with per-thread mode (-t option). Enabling call stack mode for
owner can be useful for diagnosing why a system running slow in
lock contention.
Example output:
$ sudo ~/linux/tools/perf/perf lock con -abvo -Y mutex -E16 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
2 20.88 us 11.95 us 10.44 us mutex do_epoll_wait+0x24d
0xffffffffac691f0d do_epoll_wait+0x24d
0xffffffffac693943 __x64_sys_epoll_wait+0x73
0xfffffffface604b2 do_syscall_64+0x82
0xffffffffad00012f entry_SYSCALL_64_after_hwframe+0x76
1 7.33 us 7.33 us 7.33 us mutex do_epoll_ctl+0x6c1
0xffffffffac692e01 do_epoll_ctl+0x6c1
0xffffffffac6937e0 __x64_sys_epoll_ctl+0x70
0xfffffffface604b2 do_syscall_64+0x82
0xffffffffad00012f entry_SYSCALL_64_after_hwframe+0x76
1 6.64 us 6.64 us 6.64 us mutex do_epoll_ctl+0x3d4
0xffffffffac692b14 do_epoll_ctl+0x3d4
0xffffffffac6937e0 __x64_sys_epoll_ctl+0x70
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
...
v8:
Fix compilation error found by Athira Rajeev and Namhyung Kim.
v7: lore.kernel.org/20250224184742.4144931-1-ctshao@google.com
Remove duplicate contention records.
v6: lore.kernel.org/20250219214400.3317548-1-ctshao@google.com
Free allocated memory in error patch.
Add description in man page.
v5: lore.kernel.org/20250212222859.2086080-1-ctshao@google.com
Move duplicated code into function.
Remove code to retrieve undesired callstack at the end of `contention_end()`.
Other minor fix based on Namhyung's review.
v4: lore.kernel.org/20250130052510.860318-1-ctshao@google.com
Use `__sync_fetch_and_add()` to generate owner stackid automatically.
Use `__sync_fetch_and_add(..., -1)` to workaround compiler error from
`__sync_fetch_and_sub()`
Remove unnecessary include headers.
Dedicate on C-style comment.
Other minor fix based on Namhyung's review.
v3: lore.kernel.org/20250129001905.619859-1-ctshao@google.com
Rename/shorten multiple variables.
Implement owner stackid.
Add description for lock function return code in `contention_end()`.
Other minor fix based on Namhyung's review.
v2: lore.kernel.org/20250113052220.2105645-1-ctshao@google.com
Fix logic deficit in v1 patch 2/4.
v1: lore.kernel.org/20250110051346.1507178-1-ctshao@google.com
Chun-Tse Shao (4):
perf lock: Add bpf maps for owner stack tracing
perf lock: Retrieve owner callstack in bpf program
perf lock: Make rb_tree helper functions generic
perf lock: Report owner stack in usermode
tools/perf/Documentation/perf-lock.txt | 5 +-
tools/perf/builtin-lock.c | 56 +++-
tools/perf/util/bpf_lock_contention.c | 85 +++++-
.../perf/util/bpf_skel/lock_contention.bpf.c | 245 +++++++++++++++++-
tools/perf/util/bpf_skel/lock_data.h | 7 +
tools/perf/util/lock-contention.h | 7 +
6 files changed, 372 insertions(+), 33 deletions(-)
--
2.48.1.658.g4767266eb4-goog
next reply other threads:[~2025-02-27 0:34 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-27 0:28 Chun-Tse Shao [this message]
2025-02-27 0:28 ` [PATCH v8 1/4] perf lock: Add bpf maps for owner stack tracing Chun-Tse Shao
2025-02-27 0:28 ` [PATCH v8 2/4] perf lock: Retrieve owner callstack in bpf program Chun-Tse Shao
2025-02-27 0:28 ` [PATCH v8 3/4] perf lock: Make rb_tree helper functions generic Chun-Tse Shao
2025-02-27 0:28 ` [PATCH v8 4/4] perf lock: Report owner stack in usermode Chun-Tse Shao
2025-02-27 11:11 ` [PATCH v8 0/4] Tracing contention lock owner call stack Athira Rajeev
2025-02-27 19:20 ` Chun-Tse Shao
2025-02-28 22:24 ` Namhyung Kim
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20250227003359.732948-1-ctshao@google.com \
--to=ctshao@google.com \
--cc=acme@kernel.org \
--cc=adrian.hunter@intel.com \
--cc=alexander.shishkin@linux.intel.com \
--cc=bpf@vger.kernel.org \
--cc=irogers@google.com \
--cc=jolsa@kernel.org \
--cc=kan.liang@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=nick.forrington@arm.com \
--cc=peterz@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox