Re: [PATCH] perf stat: Don't print bogus data when one event is requested

From: Jiri Olsa
Date: Wed Apr 09 2014 - 09:10:19 EST


On Thu, Mar 27, 2014 at 06:20:59PM -0400, Ramkumar Ramachandra wrote:
> When only the stalled-cycles-frontend event is requested:
>
> $ perf stat -e stalled-cycles-frontend -- git s
> ## acme...ram/acme
>
> Performance counter stats for 'git s':
>
> 326,947,423 stalled-cycles-frontend # 0.00% frontend cycles idle
>
> 0.363599976 seconds time elapsed
>
> The 0.00% frontend cycles idle comment in the output is totally bogus
> and misleading. Omit printing it here, as well as in the
> stalled-cycles-backend case.

hi,
I agree with the change, but the reason for 0% is not only that
'one' event was stated, but that 'cycles' event is missing in
measurement.

Please change your changelog accordingly, the change itself
looks ok.

thanks,
jirka
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