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	Tue, 18 Jan 2011 04:37:51 +1100 (EST)
Subject: Re: [PATCH] powerpc: perf: Fix frequency calculation for
	overflowing counters
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Scott Wood <scottwood@freescale.com>
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Date: Mon, 17 Jan 2011 18:38:01 +0100
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Cc: linux-kernel@vger.kernel.org, Paul Mackerras <paulus@samba.org>,
	Anton Blanchard <anton@samba.org>,
	Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
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On Mon, 2011-01-17 at 11:32 -0600, Scott Wood wrote:
> > diff --git a/arch/powerpc/kernel/perf_event.c b/arch/powerpc/kernel/per=
f_event.c
> > index 5674807..ab6f6be 100644
> > --- a/arch/powerpc/kernel/perf_event.c
> > +++ b/arch/powerpc/kernel/perf_event.c
> > @@ -1212,6 +1212,7 @@ static void record_and_restart(struct perf_event =
*event, unsigned long val,
> >                       if (left <=3D 0)
> >                               left =3D period;
> >                       record =3D 1;
> > +                     event->hw.last_period =3D event->hw.sample_period=
;
> >               }
> >               if (left < 0x80000000LL)
> >                       val =3D 0x80000000LL - left;

> Does perf_event_fsl_emb.c need this as well (it has almost the same
> record_and_restart code)?=20

I would think so.