Re: [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2)
From: Arnaldo Carvalho de Melo
Date: Thu Feb 10 2022 - 13:45:22 EST
Em Wed, Jan 26, 2022 at 04:00:44PM -0800, Namhyung Kim escreveu:
> 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.
>
> * changes from v1)
> - rebased onto recent acme/perf/core
> - add Jiri's Acked-by
Thanks, applied.
- Arnaldo
> 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-v2' 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: e783362eb54cd99b2cac8b3a9aeac942e6f6ac07
> --
> 2.35.0.rc0.227.g00780c9af4-goog
--
- Arnaldo