Re: [PATCH 1/4] perf, x86: Avoid checkpointed counters causingexcessive TSX aborts v4

From: Andi Kleen
Date: Fri Aug 30 2013 - 16:44:51 EST


On Fri, Aug 30, 2013 at 06:02:15PM +0200, Peter Zijlstra wrote:
> On Wed, Aug 21, 2013 at 04:47:23PM -0700, Andi Kleen wrote:
> > @@ -1224,6 +1240,15 @@ again:
> > x86_pmu.drain_pebs(regs);
> > }
> >
> > + /*
> > + * To avoid spurious interrupts with perf stat always reset checkpointed
> > + * counters.
> > + *
> > + * XXX move somewhere else.
> > + */
> > + if (cpuc->events[2] && event_is_checkpointed(cpuc->events[2]))
> > + status |= (1ULL << 2);
> > +
> > for_each_set_bit(bit, (unsigned long *)&status, X86_PMC_IDX_MAX) {
> > struct perf_event *event = cpuc->events[bit];
> >
>
> I'm sure I commented on that XXX thing..
>
> Yep, right here:

Ok.

>
> http://marc.info/?l=linux-kernel&m=137638980210140
>
> Sup?

I originally thought about precomputing the mask somewhere,
but it's not really that bad a place.

So can just drop the XXX comment. Ok?

-Andi

--
ak@xxxxxxxxxxxxxxx -- Speaking for myself only
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