Hello,

Kernel v5.19 will have a new set of tracepoints to track lock
contentions for various lock types.  Unlike tracepoints in LOCKDEP and
LOCK_STAT, it's hit only for contended locks and lock names are not
available.  So it needs to collect stack traces and display the caller
function instead.

This patchset merely adds support for the new tracepoints to the
existing perf lock commands.  So there's no change to the user.  Later
I'll add new a sub-command dedicated to the tracepoints to make use of
the additional information.

Example output:

  $ sudo perf lock record -a sleep 3
  
  $ sudo perf lock report -F acquired,contended,avg_wait

                  Name   acquired  contended   avg wait (ns)

   update_blocked_a...         40         40            3611
   kernfs_fop_open+...          5          5            3636
    _nohz_idle_balance          3          3            2650
   tick_do_update_j...          1          1            6041
    ep_scan_ready_list          1          1            3930
  ...

You can find the code in the 'perf/lock-contention-v1' branch at

  git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git

Thanks,
Namhyung


Namhyung Kim (5):
  perf lock: Change to synthesize task events
  perf lock: Add lock contention tracepoints record support
  perf lock: Handle lock contention tracepoints
  perf record: Allow to specify max stack depth of fp callchain
  perf lock: Look up callchain for the contended locks

 tools/perf/Documentation/perf-record.txt |   5 +
 tools/perf/builtin-lock.c                | 356 ++++++++++++++++++++++-
 tools/perf/util/callchain.c              |  18 +-
 3 files changed, 364 insertions(+), 15 deletions(-)


base-commit: 9dde6cadb92b5670b23b97ec53091df0530ec38b
-- 
2.36.1.255.ge46751e96f-goog