Date: Tue, 24 May 2011 16:12:49 -0400 (EDT)
From: Vince Weaver <vweaver1@eecs.utk.edu>
To: Ingo Molnar <mingo@elte.hu>
cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, linux-kernel@vger.kernel.org,
        paulus@samba.org, acme@redhat.com
Subject: Re: perf: regression -- missing
 /sys/devices/system/cpu/perf_events
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On Tue, 24 May 2011, Ingo Molnar wrote:
> 
> So, what is wrong with the method Peter suggested: the presence of the perf 
> syscall (it not returning -ENOSYS) is bona fide evidence that perf is 
> available.

it's just hard to do that from a shell script.

also, running the perf syscall can be tricky if you have a new kernel but 
an older set of header files that doesn't have the syscall number defined.

Vince
vweaver1@eecs.utk.edu
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