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Date: Sun, 27 Jan 2013 14:02:59 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Jiri Olsa <jolsa@redhat.com>
Cc: linux-kernel@vger.kernel.org, Corey Ashford <cjashfor@linux.vnet.ibm.com>,
        Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@elte.hu>,
        Namhyung Kim <namhyung@kernel.org>, Paul Mackerras <paulus@samba.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Andi Kleen <ak@linux.intel.com>, David Ahern <dsahern@gmail.com>
Subject: Re: [PATCH 0/9] perf: Adding better precise_ip field handling
Message-ID: <20130127130259.GC3933@gmail.com>
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* Jiri Olsa <jolsa@redhat.com> wrote:

> On Sun, Jan 27, 2013 at 01:41:33PM +0100, Ingo Molnar wrote:
> > 
> > * Jiri Olsa <jolsa@redhat.com> wrote:
> > 
> > > hi,
> > > adding sysfs attribute to specify the maximum allowed value
> > > for perf_event_attr::precise_ip field.
> > > 
> > > Adding functionality for simple 'precise' term to get the
> > > maximum allowed value for perf_event_attr::precise_ip field.
> > > 
> > > And finally adding several precise automated tests.
> > 
> > Ok - could we please as a next step turn on cycles:pp as the 
> > default in all the profiling tools (perf record, perf top), 
> > transparently? I.e. if the CPU supports it then use it, if not 
> > then don't complain, just use the highest grade profiling method 
> > available.
> 
> yep, we discussed with Arnaldo this would be good to have

This would be a high-profile, user visible improvement to 
profiling quality.

Thanks,

	Ingo