Re: [PATCH 1/5] perf, x86: Don't assume the alternative cycles encoding is architectural

Peter Zijlstra
2012-06-06T10:40:01Z

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.