From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: Question about Perf's handling of in-use performance counters
Date: Thu, 27 Oct 2016 23:00:12 +0200
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To: Andi Kleen <andi@firstfloor.org>
Cc: Taylor Andrews <andrewst@vmware.com>, "linux-perf-users@vger.kernel.org" <linux-perf-users@vger.kernel.org>

On Thu, Oct 27, 2016 at 11:11:24AM -0700, Andi Kleen wrote:
> 
> Taylor Andrews <andrewst@vmware.com> writes:
> 
> > First some background:
> >
> > VMware's virtual x86 performance counter implementation aims to expose
> > in-use (unavailable) performance counters to the guest operating
> > system in the hopes that software agents will recognize it as an
> > "in-use" resource and follow the PMU sharing guidelines outlined in
> > Intel's Performance Monitoring Unit Sharing Guide
> > (https://software.intel.com/en-us/articles/performance-monitoring-unit-guidelines/).

I would have to dig out the thread, but that wasn't followed on purpose
and is unlikely to ever be followed.