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Subject: Re: [RFC][PATCH 3/9] perf: export registerred pmus via sysfs
From: Peter Zijlstra <peterz@infradead.org>
To: Lin Ming <ming.m.lin@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>, Frederic Weisbecker <fweisbec@gmail.com>,
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Date: Mon, 10 May 2010 11:40:01 +0200
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On Mon, 2010-05-10 at 17:27 +0800, Lin Ming wrote:
> Export pmus via sysfs /sys/devices/system/cpu/pmus/0...N
> The file name is the pmu id, ie, /sys/devices/system/cpu/pmus/N
> represents pmu id N.
> So perf tool can use it to initialize perf_event_attr. 

Why create a whole new directory, why not:

 /sys/devices/system/cpu/cpuN/pmu_id ?

That way we can simply extend it to things like:

 /sys/devices/system/cpu/cpuN/nodeN/pmu_id
 /sys/devices/system/node/nodeN/pmi_id

Instead of having to add something like:

 /sys/devices/system/node/pmus/0..N