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Message-ID: <1373885096.3146.11.camel@hornet>
Subject: Re: [RFC] perf: need to expose sched_clock to correlate user
 samples with kernel samples
From: Pawel Moll <pawel.moll@arm.com>
To: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
        Stephane Eranian <eranian@google.com>, Ingo Molnar <mingo@kernel.org>,
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        "ak@linux.intel.com" <ak@linux.intel.com>,
        Pekka Enberg <penberg@gmail.com>, Steven Rostedt <rostedt@goodmis.org>,
        Robert Richter <robert.richter@amd.com>, tglx <tglx@linutronix.de>,
        John Stultz <john.stultz@linaro.org>
Date: Mon, 15 Jul 2013 11:44:56 +0100
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On Wed, 2013-06-26 at 17:49 +0100, David Ahern wrote:
> With all the perf ioctl extensions tossed out the past day or so I 
> wanted to revive this request. Still need a solution to the problem of 
> correlating perf_clock to other clocks ...

And I second. We've been trying to squeeze the solution into the posix
clock framework (and vdso) but it didn't get anywhere, really. I've
spoken to John last week and although there is one more potential
"solution" (and the quotes are meaningful ;-), it seems that the
perf-specific ioctl would work for all interested individuals for now.

Paweł