Re: [tip:perf/urgent] perf/x86/cqm: Fix CQM handling of grouping events into a cache_group
From: Matt Fleming
Date: Mon Mar 21 2016 - 10:57:49 EST
On Mon, 21 Mar, at 02:51:29AM, tip-bot for Vikas Shivappa wrote:
> Commit-ID: a223c1c7ab4cc64537dc4b911f760d851683768a
> Gitweb: http://git.kernel.org/tip/a223c1c7ab4cc64537dc4b911f760d851683768a
> Author: Vikas Shivappa <vikas.shivappa@xxxxxxxxxxxxxxx>
> AuthorDate: Thu, 10 Mar 2016 15:32:07 -0800
> Committer: Ingo Molnar <mingo@xxxxxxxxxx>
> CommitDate: Mon, 21 Mar 2016 09:08:18 +0100
>
> perf/x86/cqm: Fix CQM handling of grouping events into a cache_group
>
> Currently CQM (cache quality of service monitoring) is grouping all
> events belonging to same PID to use one RMID. However its not counting
> all of these different events. Hence we end up with a count of zero
> for all events other than the group leader.
The reason that was done originally was because reporting for all events
in a group led to duplicate values, since you'd be emitting the same
RMID value multiple times.
Is this no longer a problem?