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Date: Thu, 2 Nov 2017 15:56:45 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: "Liang, Kan" <kan.liang@intel.com>
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Subject: RE: [PATCH V3 1/5] perf/x86/intel/uncore: customized pmu event read
 for client IMC uncore
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On Thu, 2 Nov 2017, Liang, Kan wrote:
> > On Thu, 2 Nov 2017, Thomas Gleixner wrote:
> > But then you have this in uncore_perf_event_update():
> > 
> > -       if (event->hw.idx >= UNCORE_PMC_IDX_FIXED)
> > +       if (event->hw.idx == UNCORE_PMC_IDX_FIXED)
> > 
> > So how is that supposed to work?
> 
> This is for generic code. 
> 
> In previous code, the event_read function for IMC use generic code.
> So we have to deal with >= in generic code.
> 
> Now, customized event_read function 'snb_uncore_imc_event_read'
>  is introduced for IMC. So IMC does not touch the generic code. 
> The generic code is corrected here.

The customized read function does not help at all.

uncore_perf_event_update() is used from snb_uncore_imc_event_stop(). So
it's broken with this patch.

This is a complete and utter mess to review.

Thanks,

	tglx