Re: [PATCH v4 3/4] perf-stat: introduce config stat.bpf-counter-events
From: Jiri Olsa
Date: Sun Apr 25 2021 - 11:17:24 EST
On Sun, Apr 25, 2021 at 11:38:43AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Wed, Apr 21, 2021 at 12:18:23PM +0200, Jiri Olsa escreveu:
> > On Tue, Apr 20, 2021 at 09:21:32PM +0000, Song Liu wrote:
> > >
> > >
> > > > On Apr 20, 2021, at 10:31 AM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
> > > >
> > > > On Mon, Apr 19, 2021 at 01:36:48PM -0700, Song Liu wrote:
> > > >
> > > > SNIP
> > > >
> > > >> if (stat_config.initial_delay < 0) {
> > > >> @@ -784,11 +790,11 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
> > > >> if (affinity__setup(&affinity) < 0)
> > > >> return -1;
> > > >>
> > > >> - if (target__has_bpf(&target)) {
> > > >> - evlist__for_each_entry(evsel_list, counter) {
> > > >> - if (bpf_counter__load(counter, &target))
> > > >> - return -1;
> > > >> - }
> > > >> + evlist__for_each_entry(evsel_list, counter) {
> > > >> + if (bpf_counter__load(counter, &target))
> > > >> + return -1;
> > > >> + if (!evsel__is_bpf(counter))
> > > >> + all_counters_use_bpf = false;
> > > >
> > > > could be done in bpf_counter__load, check below:
> > > >
> > > >> }
> > > >>
> > > >> evlist__for_each_cpu (evsel_list, i, cpu) {
> > > >> diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c
> > > >> index 5de991ab46af9..33b1888103dfa 100644
> > > >> --- a/tools/perf/util/bpf_counter.c
> > > >> +++ b/tools/perf/util/bpf_counter.c
> > > >> @@ -790,7 +790,8 @@ int bpf_counter__load(struct evsel *evsel, struct target *target)
> > > >> {
> > > >> if (target->bpf_str)
> > > >> evsel->bpf_counter_ops = &bpf_program_profiler_ops;
> > > >> - else if (target->use_bpf)
> > > >> + else if (target->use_bpf ||
> > > >> + evsel__match_bpf_counter_events(evsel->name))
> > > >> evsel->bpf_counter_ops = &bperf_ops;
> > > >
> > > > with:
> > > > else
> > > > all_counters_use_bpf = false;
> > > >
> > > > I was also thinking of oving it to evlist, but it's sat specific,
> > > > so I think it's good as static.. thanks for changing the implementation
> > >
> > > Hmm... then we need to somehow make all_counters_use_bpf visible in
> > > bpf_counter.c, which won't be very clean. Also, since this is stat
> > > specific, I guess it is better to keep it inside builtin-stat.c?
> > > The runtime overhead should be minimal.
> >
> > ah it's different file :) then it's better as it is, sorry
>
> Is this a Reviewed-by?
there's still the matter of disable callback:
https://lore.kernel.org/lkml/YH8Pw4m0w6DuuEXo@krava/
it looks like now it could wrong value if we don't disable it
jirka