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Message-ID: <1338979188.2749.92.camel@twins>
Subject: Re: [PATCH 1/5] perf, x86: Don't assume the alternative cycles
 encoding is architectural
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Andi Kleen <andi@firstfloor.org>
Cc: linux-kernel@vger.kernel.org, eranian@google.com,
        Andi Kleen <ak@linux.intel.com>
Date: Wed, 06 Jun 2012 12:39:48 +0200
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On Tue, 2012-06-05 at 17:56 -0700, Andi Kleen wrote:
> From: Andi Kleen <ak@linux.intel.com>
> 
> cycles:p uses an special cycles encoding by default. However that is not
> architectural, so it can only be used when the CPU is known
> (it already caused problems on Sandy Bridge). It may or may not work
> on future CPUs.
> 
> So make it opt-in only. Right now I enabled it on Core2, Nehalem, Westmere
> and not on Sandy-Bridge or Atom.

No. Also, c0 is a PEBS capable event on Atom just fine.