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Date: Tue, 9 Apr 2013 07:02:50 +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>,
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        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 Mon, Apr 08, 2013 at 12:05:52PM -0700, John Stultz wrote:
> 
> So thinking this through further, I'm worried we may _not_ be able
> to eventually enable this to be a vdso as I had earlier hoped.
> Mostly because I'm not sure how the fd -> file -> clock lookup could
> be done in userland (any ideas?).

How about a new clock operation, clock_install_vdso(), that lets the
process arrange for one dynamic clock to be reflected in its vdso
page?

Thanks,
Richard