From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Subject: Re: [PATCH cgroup/for-4.15] cgroup, sched: Move basic cpu stats from
 cgroup.stat to cpu.stat
Date: Tue, 24 Oct 2017 10:35:04 +0200
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To: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Roman Gushchin <guro-b10kYP2dOMg@public.gmane.org>, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kernel-team-b10kYP2dOMg@public.gmane.org

On Mon, Oct 23, 2017 at 04:18:27PM -0700, Tejun Heo wrote:
> The basic cpu stat is currently shown with "cpu." prefix in
> cgroup.stat, and the same information is duplicated in cpu.stat when
> cpu controller is enabled.  This is ugly and not very scalable as we
> want to expand the coverage of stat information which is always
> available.
> 
> This patch makes cgroup core always create "cpu.stat" file and show
> the basic cpu stat there and calls the cpu controller to show the
> extra stats when enabled.  This ensures that the same information
> isn't presented in multiple places and makes future expansion of basic
> stats easier.
> 
> Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> ---
> Hello,
> 
> The more I think about showing cpu stat in cgroup.stat, the uglier it
> seems. 

I've not been paying much attention to this, could you elaborate on the
problems there?

> This patch flips it so that "cpu.stat" is always available
> with basic cpu stat instead.  It only changes the presentation and
> changes to the scheduler code is minimal.  Will route with the other
> cpu controller changes through cgroup/for-4.15 unless there are
> objections.

And this is -v2 only? I'm a little lost on how all that connects.