Date: Thu, 4 Apr 2013 09:37:00 +0200
From: Richard Cochran <richardcochran@gmail.com>
To: John Stultz <john.stultz@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>, Peter Zijlstra <peterz@infradead.org>,
        David Ahern <dsahern@gmail.com>, Stephane Eranian <eranian@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, "mingo@elte.hu" <mingo@elte.hu>,
        Paul Mackerras <paulus@samba.org>, Anton Blanchard <anton@samba.org>,
        Will Deacon <Will.Deacon@arm.com>,
        "ak@linux.intel.com" <ak@linux.intel.com>,
        Pekka Enberg <penberg@gmail.com>, Steven Rostedt <rostedt@goodmis.org>,
        Robert Richter <robert.richter@amd.com>
Subject: Re: [RFC] perf: need to expose sched_clock to correlate user
 samples with kernel samples
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On Wed, Apr 03, 2013 at 10:50:57AM -0700, John Stultz wrote:
> 
> I get the reasoning around reusing the fd we already have, but is
> the possibility of a dynamic chardev pathname really a big concern?

I have been following this thread, and, not knowing very much about
perf, I would think that the userland can easily open a second file
(the dynamic posix clock chardev) in order to get these time stamps.

> Maybe can we extend the dynamic posix clock code to work on more
> then just the chardev? Although I worry about multiplexing too much
> functionality on the file.

I don't yet see a need for that, but if we do, then it should work in
a generic way, and not as a list of special cases, like we saw in the
patch.

Thanks,
Richard
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