Messages in this thread | | | From | Ian Rogers <> | Date | Thu, 28 Mar 2024 09:02:31 -0700 | Subject | Re: [PATCH 1/2] perf sched timehist: Fix -g/--call-graph option failure |
| |
On Wed, Mar 27, 2024 at 10:59 PM Yang Jihong <yangjihong@bytedance.com> wrote: > > When perf-sched enables the call-graph recording, sample_type of dummy > event does not have PERF_SAMPLE_CALLCHAIN, timehist_check_attr() checks > that the evsel does not have a callchain, and set show_callchain to 0. > > Currently perf sched timehist only saves callchain when processing > sched:sched_switch event, timehist_check_attr() only needs to determine > whether the event has PERF_SAMPLE_CALLCHAIN. > > Before: > # perf sched record -g true > [ perf record: Woken up 0 times to write data ] > [ perf record: Captured and wrote 4.153 MB perf.data (7536 samples) ] > # perf sched timehist > Samples do not have callchains. > time cpu task name wait time sch delay run time > [tid/pid] (msec) (msec) (msec) > --------------- ------ ------------------------------ --------- --------- --------- > 147851.826019 [0000] perf[285035] 0.000 0.000 0.000 > 147851.826029 [0000] migration/0[15] 0.000 0.003 0.009 > 147851.826063 [0001] perf[285035] 0.000 0.000 0.000 > 147851.826069 [0001] migration/1[21] 0.000 0.003 0.006 > <SNIP> > > After: > # perf sched record -g true > [ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 2.572 MB perf.data (822 samples) ] > # perf sched timehist > time cpu task name wait time sch delay run time > [tid/pid] (msec) (msec) (msec) > --------------- ------ ------------------------------ --------- --------- --------- > 144193.035164 [0000] perf[277062] 0.000 0.000 0.000 __traceiter_sched_switch <- __traceiter_sched_switch <- __sched_text_start <- preempt_schedule_common <- __cond_resched <- __wait_for_common <- wait_for_completion > 144193.035174 [0000] migration/0[15] 0.000 0.003 0.009 __traceiter_sched_switch <- __traceiter_sched_switch <- __sched_text_start <- smpboot_thread_fn <- kthread <- ret_from_fork > 144193.035207 [0001] perf[277062] 0.000 0.000 0.000 __traceiter_sched_switch <- __traceiter_sched_switch <- __sched_text_start <- preempt_schedule_common <- __cond_resched <- __wait_for_common <- wait_for_completion > 144193.035214 [0001] migration/1[21] 0.000 0.003 0.007 __traceiter_sched_switch <- __traceiter_sched_switch <- __sched_text_start <- smpboot_thread_fn <- kthread <- ret_from_fork > <SNIP>
This looks good, should there be a Fixes tag for the sake of backports?
Thanks, Ian
> Signed-off-by: Yang Jihong <yangjihong@bytedance.com> > --- > tools/perf/builtin-sched.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c > index b248c433529a..1bfb22347371 100644 > --- a/tools/perf/builtin-sched.c > +++ b/tools/perf/builtin-sched.c > @@ -2963,8 +2963,11 @@ static int timehist_check_attr(struct perf_sched *sched, > return -1; > } > > - if (sched->show_callchain && !evsel__has_callchain(evsel)) { > - pr_info("Samples do not have callchains.\n"); > + /* only need to save callchain related to sched_switch event */ > + if (sched->show_callchain && > + evsel__name_is(evsel, "sched:sched_switch") && > + !evsel__has_callchain(evsel)) { > + pr_info("Samples of sched_switch event do not have callchains.\n"); > sched->show_callchain = 0; > symbol_conf.use_callchain = 0; > } > -- > 2.25.1 >
| |