Re: [RFC PATCH 2/3 v3] perf: Implement Nehalem uncore pmu

From: Cyrill Gorcunov
Date: Fri Dec 10 2010 - 10:11:46 EST


On Fri, Dec 10, 2010 at 11:52:15AM +0100, Peter Zijlstra wrote:
> On Fri, 2010-12-10 at 11:47 +0100, Peter Zijlstra wrote:
> > On Fri, 2010-12-10 at 00:46 +0100, Stephane Eranian wrote:
> > > Hi,
> > >
> > > So I have tested this patch a bit on WSM and as I expected there
> > > are issues with sampling.
> > >
> > > When HT is on, both siblings CPUs get the interrupt. The HW does not
> > > allow you to only point interrupts to a single HT thread (CPU).
> >
> > Egads, how ugly :/
> >

crap...
...

>
> That would of course need to also grow some smarts to detect if there is
> only 1 sibling online.
>
> CC'ed Cyrill as P4 might have something similar.
>

Yes, Don was testing p4 stuff for me and have reported this issue as well.
I'll check what I can do. Thanks for CC'ing me.

Cyrill
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