Re: [PATCH 2/5] perf, x86: Enable PDIR precise instruction profilingon IvyBridge

From: Andi Kleen
Date: Thu Jul 05 2012 - 13:26:52 EST


On Thu, Jul 05, 2012 at 05:45:16PM +0200, Stephane Eranian wrote:
> On Tue, Jul 3, 2012 at 6:04 AM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:
> >> Well, the only way I can think of would be to request that the
> >> event be programmed with exclusive mode ALWAYS. That
> >> should not be to hard to add.
> >
> > I suspect it would need some special callbacks from the events core,
> > that's why I only tried on IvyBridge.
> >x
> You could simply add a check in the x86 init code like what is done
> with the pebs events and precise mode.

Ah requiring the user to set exclusive? Maybe. Right now perf does not even
have an option to set it. Would seem user unfriendly to me though.

-Andi
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