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Date: Mon, 7 Dec 2015 11:26:51 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: vincent.weaver@maine.edu, jolsa@redhat.com, torvalds@linux-foundation.org,
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        Arnaldo Carvalho de Melo <acme@infradead.org>
Subject: Re: [tip:perf/core] perf/x86: Use INST_RETIRED.PREC_DIST for cycles:
 ppp
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On Mon, Dec 07, 2015 at 07:48:41AM +0100, Ingo Molnar wrote:
> 
> * Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > On Sun, Dec 06, 2015 at 02:11:02PM +0100, Ingo Molnar wrote:
> >
> > > Also, I'm not convinced we need a new 'ppp' qualifier for any of this, why not 
> > > just replace 'pp' with this event - 'pp' is meant to be our most precise 
> > > event.
> > 
> > I requested this because the PREC_DIST events can only be scheduled on a single 
> > counter, whereas the existing :pp events can be had on all 4.
> > 
> > This mean you can have 2 concurrent :pp users (without RR), but not :ppp.
> 
> Ok. Will tooling do the right thing? I.e. will the first user of 'perf top' get 
> :ppp automatically, while the second one falls back to :pp?

if not I'll make it so.