Re: [PATCH 2/2] perf, tools, stat: Reset ids counter when retrying events

From: Jiri Olsa
Date: Wed Feb 21 2018 - 09:31:30 EST


On Thu, Oct 05, 2017 at 07:00:29PM -0700, Andi Kleen wrote:
> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

ouch, sry for overlooking this

>
> perf stat can retry opening events. After opening an file descriptor
> it adds the ids to the ecsel. Each event keeps a running
> count of ids. When we decide to close an evsel and retry
> with a different configuration this count needs to be reset,
> otherwise it can overflow the buffer.

how can this happen? we call store_counter_ids at the
end of the loop, when the evsel is all done and can't
be reconfigured

thanks,
jirka