Re: [PATCH 3/4] perf/x86/intel/ds: Handle PEBS overflow for fixed counters

[Liang, Kan]

On 7/23/2018 12:21 PM, Peter Zijlstra wrote:
> On Mon, Jul 23, 2018 at 04:59:44PM +0200, Peter Zijlstra wrote:
> > On Thu, Mar 08, 2018 at 06:15:41PM -0800, kan.liang@xxxxxxxxxxxxxxx wrote:
> > > diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
> > > index ef47a418d819..86149b87cce8 100644
> > > --- a/arch/x86/events/intel/core.c
> > > +++ b/arch/x86/events/intel/core.c
> > > @@ -2280,7 +2280,10 @@ static int intel_pmu_handle_irq(struct pt_regs *regs)
> > >   	 * counters from the GLOBAL_STATUS mask and we always process PEBS
> > >   	 * events via drain_pebs().
> > >   	 */
> > > -	status &= ~(cpuc->pebs_enabled & PEBS_COUNTER_MASK);
> > > +	if (x86_pmu.flags & PMU_FL_PEBS_ALL)
> > > +		status &= ~(cpuc->pebs_enabled & EXTENDED_PEBS_COUNTER_MASK);
> > > +	else
> > > +		status &= ~(cpuc->pebs_enabled & PEBS_COUNTER_MASK);
> > >   
> > >   	/*
> > >   	 * PEBS overflow sets bit 62 in the global status register
> >
> > Doesn't this re-introduce the problem fixed in commit fd583ad1563be,
> > where pebs_enabled:32-34 are PEBS Load Latency, instead of fixed
> > counters?
>
> Also, since they 'fixed' that conflict, the PEBS_ALL version could be:
>
> 	state &= cpuc->pebs_enabled;
>
> Right?

Right.

Thanks,
Kan