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Subject: Re: [RFC] [PATCH] perf: Attaching an event to a specific PMU
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Ingo Molnar <mingo@elte.hu>
Cc: Robert Richter <robert.richter@amd.com>, Paul Mackerras <paulus@samba.org>,
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Date: Wed, 06 Jul 2011 19:14:41 +0200
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On Wed, 2011-07-06 at 19:10 +0200, Ingo Molnar wrote:
> 
> I think Peter suggested it that an open() done in /sys should give us 
> a handle to a given event? 

No, more like the open of a sysfs file could also grab a refcount on the
module. All it would take is a custom open/close method for sysfs files.
Now I have no clue how to do that, but that's another issue.

Also, I really don't see the point. With modular PMUs there's always
races against unload, just don't do that or live with it.