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Date: Wed, 19 May 2010 09:23:32 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@amd64.org>, Lin Ming <ming.m.lin@intel.com>,
       Greg KH <greg@kroah.com>, Corey Ashford <cjashfor@linux.vnet.ibm.com>,
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       Carl Love <carll@us.ibm.com>, Kay Sievers <kay.sievers@vrfy.org>,
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Subject: Re: [RFC][PATCH v2 06/11] perf: core, export pmus via sysfs
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* Peter Zijlstra <peterz@infradead.org> wrote:

> On Wed, 2010-05-19 at 09:06 +0200, Borislav Petkov wrote:
> > 
> > have we considered the per-cpu granularity of MCEs 
> > here and if yes, how to represent that?
> 
> Uhm, by opening the MCE event on a particular cpu? 
> Remember that sys_perf_event_open() has a cpu target.
> 
> The thing is, CPUs are assumed symmetric, thus also all 
> MCE events are symmetric, one CPU cannot generate other 
> MCE than another. So the only thing that differs is 
> where you want to listen for them.

Note, this does not preclude Linux from supporting 
assymetric MP, should the need arise: if MP assymetry is 
supported then that can (and should) be expressed in the 
sysfs topology accordingly - and the moment the assymetric 
MP topology is enumerated in sysfs it gives a place for 
the different event_source's to live there as well.

Thanks,

	Ingo