summary refs log tree commit diff
path: root/tools/perf/Documentation
diff options
context:
space:
mode:
authorNamhyung Kim <namhyung@kernel.org>2022-07-25 11:31:22 -0700
committerArnaldo Carvalho de Melo <acme@redhat.com>2022-07-25 17:55:51 -0300
commit528b9cab3b813a3b94a4af14845308f720eb13fd (patch)
tree600787048f94add041565acd3596c0d3d7da5dea /tools/perf/Documentation
parentf9c695a21103bb1665aaa87c7592ac17303fc160 (diff)
downloadlinux-528b9cab3b813a3b94a4af14845308f720eb13fd.tar.gz
perf lock: Add 'contention' subcommand
The 'perf lock contention' processes the lock contention events and
displays the result like perf lock report.  Right now, there's not
much difference between the two but the lock contention specific
features will come soon.

  $ perf lock contention
   contended   total wait     max wait     avg wait         type   caller

         238      1.41 ms     29.20 us      5.94 us     spinlock   update_blocked_averages+0x4c
           1    902.08 us    902.08 us    902.08 us      rwsem:R   do_user_addr_fault+0x1dd
          81    330.30 us     17.24 us      4.08 us     spinlock   _nohz_idle_balance+0x172
           2     89.54 us     61.26 us     44.77 us     spinlock   do_anonymous_page+0x16d
          24     78.36 us     12.27 us      3.27 us        mutex   pipe_read+0x56
           2     71.58 us     59.56 us     35.79 us     spinlock   __handle_mm_fault+0x6aa
           6     25.68 us      6.89 us      4.28 us     spinlock   do_idle+0x28d
           1     18.46 us     18.46 us     18.46 us      rtmutex   exec_fw_cmd+0x21b
           3     15.25 us      6.26 us      5.08 us     spinlock   tick_do_update_jiffies64+0x2c

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220725183124.368304-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/Documentation')
-rw-r--r--tools/perf/Documentation/perf-lock.txt4
1 files changed, 3 insertions, 1 deletions
diff --git a/tools/perf/Documentation/perf-lock.txt b/tools/perf/Documentation/perf-lock.txt
index 4b8568f0c53b..da0bcbc676a3 100644
--- a/tools/perf/Documentation/perf-lock.txt
+++ b/tools/perf/Documentation/perf-lock.txt
@@ -8,7 +8,7 @@ perf-lock - Analyze lock events
 SYNOPSIS
 --------
 [verse]
-'perf lock' {record|report|script|info}
+'perf lock' {record|report|script|info|contention}
 
 DESCRIPTION
 -----------
@@ -27,6 +27,8 @@ and statistics with this 'perf lock' command.
   'perf lock info' shows metadata like threads or addresses
   of lock instances.
 
+  'perf lock contention' shows contention statistics.
+
 COMMON OPTIONS
 --------------