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Date: Tue, 22 Nov 2011 11:52:21 +0000
From: Will Deacon <will.deacon@arm.com>
To: Oleg Strikov <OSTRIKOV@nvidia.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, "mingo@elte.hu" <mingo@elte.hu>,
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Subject: Re: [RFC][PATCH 2/6] perf, arch: Rework perf_event_index()
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On Tue, Nov 22, 2011 at 11:49:41AM +0000, Oleg Strikov wrote:
> > The user-readable clock will first appear in Cortex-A15, so the code for that still needs to hit mainline before I can look at doing this in perf.
> 
> This could be very useful. I think that the cycles counter covers the 90% of all the in-app profiler needs.

Well, it's slightly different to the cycle counter in that it will continue
to count when the core is idle. The PMU cycle counter may stop when you
issue a WFI. The frequency of the clock is also unlikely to be the same as
the CPU clock.

Will