Messages in this thread | | | Date | Tue, 30 Jan 2018 19:52:12 +0100 | From | Jiri Olsa <> | Subject | Re: [PATCH V3 0/5] bugs fix for large PEBS mmap read and rdpmc read |
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On Tue, Jan 30, 2018 at 11:48:18AM -0500, Liang, Kan wrote:
SNIP
> > > > > > The events in fixed mode could enable large PEBS. Events in freq mode should > > > not enable large PEBS. > > > I think that could be a problem if some events try to enable large PEBS, > > > while others not. > > > > > You only enable large PEBS if 100% of the events use fixed periods, > > either via -c period > > or because they all use individual period=p. The --no-period could > > also be used to remove > > the period for measurements where the period is not needed. > > > Oh, right, the kernel has already guaranteed that. > if (cpuc->n_pebs == cpuc->n_large_pebs) { > threshold = ds->pebs_absolute_maximum - > x86_pmu.max_pebs_events * x86_pmu.pebs_record_size; > } else { > > Sorry for the noise. > > jirka's patch looks good to me.
cool, I'll post it later this week
thanks, jirka
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