Re: [PATCH V2 1/1] perf/core: don't find side-band event from all pmus

From: acme@xxxxxxxxxx
Date: Thu Mar 31 2016 - 10:26:13 EST


Em Thu, Mar 31, 2016 at 02:05:46PM +0000, Liang, Kan escreveu:
>
>
> > > +static void perf_event_sb_mask(unsigned int sb_mask,
> > > + perf_event_aux_output_cb output,
> > > + void *data)
> > > +{
> > > + int sb;
> > > +
> > > + for (sb = 0; sb < sb_nr; sb++) {
> > > + if (!(sb_mask & (1 << sb)))
> > > + continue;
> > > + perf_event_sb_iterate(sb, output, data);
> > > + }
> > > +}
> >
> > > @@ -5852,7 +5910,8 @@ static void perf_event_task(struct task_struct
> > > *task,
> > >
> > > perf_event_aux(perf_event_task_output,
> > > &task_event,
> > > - task_ctx);
> > > + task_ctx,
> > > + (1 << sb_task) | (1 << sb_mmap) | (1 << sb_comm));
> > > }
> >
> > So one side-effect of this change is that the above event can be delivered
> > 3 times if you're 'lucky'.
> >
> > Acme; does userspace care?
>
> Hi Arnaldo,
>
> Do you think if it's an issue for userspace?

Trying to get context and decode what you guys wrote...

- Arnaldo