Re: [PATCH] perf evsel: Fix missing inherit + sample read check

[Ben Gainey <Ben.Gainey@arm.com>]

On Fri, 2024-10-11 at 09:39 -0700, Namhyung Kim wrote:
> On Fri, Oct 11, 2024 at 08:02:04AM +0000, Ben Gainey wrote:
> > On Tue, 2024-10-08 at 23:22 -0700, Namhyung Kim wrote:
> > > It should not clear the inherit bit simply because the kernel
> > > doesn't
> > > support the sample read with it.  IOW the inherit bit should be
> > > kept
> > > when the sample read is not requested for the event.
> > 
> > 
> > Ah, sorry. Good spot.
> 
> Thanks for the review, can I translate it your Acked-by?
> 

Yes, of course

Acked-by: Ben Gainey <ben.gainey@arm.com>

:-)


> Thanks,
> Namhyung
>  
> > > 
> > > Fixes: 90035d3cd876cb71 ("tools/perf: Allow inherit +
> > > PERF_SAMPLE_READ when opening events")
> > > Cc: Ben Gainey <ben.gainey@arm.com>
> > > Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> > > ---
> > >  tools/perf/util/evsel.c | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> > > index d8fd493af01458b7..507f526ccbbcfc36 100644
> > > --- a/tools/perf/util/evsel.c
> > > +++ b/tools/perf/util/evsel.c
> > > @@ -2112,7 +2112,8 @@ static int __evsel__prepare_open(struct
> > > evsel
> > > *evsel, struct perf_cpu_map *cpus,
> > >  
> > >  static void evsel__disable_missing_features(struct evsel *evsel)
> > >  {
> > > - if (perf_missing_features.inherit_sample_read)
> > > + if (perf_missing_features.inherit_sample_read && evsel-
> > > > core.attr.inherit &&
> > > +     (evsel->core.attr.sample_type & PERF_SAMPLE_READ))
> > >   evsel->core.attr.inherit = 0;
> > >   if (perf_missing_features.branch_counters)
> > >   evsel->core.attr.branch_sample_type &=
> > > ~PERF_SAMPLE_BRANCH_COUNTERS;
> >