[PATCHSET 0/6] perf lock: Random updates for the locking analysis (v1)

[Namhyung Kim]

Hello,

I have some updates in the perf lock command (focused on 'report').
The main change is to add -c (or --combine-locks) option to aggregate
results based on lock class name.

Without this option, the result deals with lock addresses so instances
in the same lock class will have separate entries like below:

  # perf lock report
                  Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns) 

         rcu_read_lock     251225          0               0               0               0               0 
   &(ei->i_block_re...       8731          0               0               0               0               0 
   &sb->s_type->i_l...       8731          0               0               0               0               0 
   hrtimer_bases.lo...       5261          0               0               0               0               0 
   hrtimer_bases.lo...       2626          0               0               0               0               0 
   hrtimer_bases.lo...       1953          0               0               0               0               0 
   hrtimer_bases.lo...       1382          0               0               0               0               0 
   cpu_hotplug_lock...       1350          0               0               0               0               0 
   hrtimer_bases.lo...       1273          0               0               0               0               0 
   hrtimer_bases.lo...       1269          0               0               0               0               0 
   hrtimer_bases.lo...       1198          0               0               0               0               0 
   hrtimer_bases.lo...       1116          0               0               0               0               0 
           &base->lock       1109          0               0               0               0               0 
   hrtimer_bases.lo...       1067          0               0               0               0               0 
   hrtimer_bases.lo...       1052          0               0               0               0               0 
   hrtimer_bases.lo...        957          0               0               0               0               0 
   hrtimer_bases.lo...        948          0               0               0               0               0 
          css_set_lock        791          0               0               0               0               0 
   hrtimer_bases.lo...        752          0               0               0               0               0 
   &lruvec->lru_loc...        747          5           11254           56272           18317            1412 
   hrtimer_bases.lo...        738          0               0               0               0               0 
   &newf->file_lock...        706         15            1025           15388            2279             618 
   hrtimer_bases.lo...        702          0               0               0               0               0 
   hrtimer_bases.lo...        694          0               0               0               0               0 
  ...

With -c option, the hrtimer_bases.lock would be combined into a single
entry.  Also note that the lock names are correctly displayed now.

  # perf lock report -c
                  Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns) 
  
         rcu_read_lock     251225          0               0               0               0               0 
    hrtimer_bases.lock      39449          0               0               0               0               0 
   &sb->s_type->i_l...      10301          1             662             662             662             662 
      ptlock_ptr(page)      10173          2             701            1402             760             642 
   &(ei->i_block_re...       8732          0               0               0               0               0 
           &base->lock       6705          0               0               0               0               0 
           &p->pi_lock       5549          0               0               0               0               0 
   &dentry->d_lockr...       5010          4            1274            5097            1844             789 
             &ep->lock       2750          0               0               0               0               0 
   &(__futex_data.q...       2331          0               0               0               0               0 
                (null)       1878          0               0               0               0               0 
      cpu_hotplug_lock       1350          0               0               0               0               0 
      &____s->seqcount       1349          0               0               0               0               0 
      &newf->file_lock       1001         15            1025           15388            2279             618 
  ...

Maybe we can make it default later (with a config and --no-combine-locks).

You can get it from 'perf/lock-combine-v1' branch at

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

Thanks,
Namhyung


Namhyung Kim (6):
  perf lock: Convert lockhash_table to use hlist
  perf lock: Change type of lock_stat->addr to u64
  perf lock: Sort map info based on class name
  perf lock: Fix lock name length check for printing
  perf lock: Add -c/--combine-locks option
  perf lock: Carefully combine lock stats for discarded entries

 tools/perf/Documentation/perf-lock.txt |   4 +
 tools/perf/builtin-lock.c              | 155 +++++++++++++++++++------
 2 files changed, 124 insertions(+), 35 deletions(-)


base-commit: b9f6fbb3b2c29736970ae9fcc0e82b0bd459442b
-- 
2.34.1.448.ga2b2bfdf31-goog