From mboxrd@z Thu Jan  1 00:00:00 1970
From: Juri Lelli <juri.lelli-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: [RFC PATCH 0/2] sched/cpuset: Fix DL BW accounting in case
 can_attach() fails
Date: Thu, 23 Mar 2023 10:33:22 +0100
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To: Dietmar Eggemann <dietmar.eggemann-5wv7dgnIgG8@public.gmane.org>
Cc: Ingo Molnar <mingo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, Waiman Long <longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Zefan Li <lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Hao Luo <haoluo-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Steven Rostedt <rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org>, Vincent Guittot <vincent.guittot-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Daniel Bristot de Oliveira <bristot-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Luca Abeni <luca.abeni-5rdYK369eBLQB0XuIGIEkQ@public.gmane.org>, Tommaso Cucinotta <tommaso.cucinotta-5rdYK369eBLQB0XuIGIEkQ@public.gmane.org>, Qais Yousef <qyousef-wp2msK0BRk8tq7phqP6ubQ@public.gmane.org>, Wei Wang <wvw-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

Hi,

On 22/03/23 14:59, Dietmar Eggemann wrote:
> I followed Longman's idea to add a `deadline task transfer count` into
> cpuset and only update the `dl task count` in cpuset_attach().
> 
> Moreover, I switched from per-task DL BW request to a per-cpuset one.
> This way we don't have to free per-task in case xxx_can_attach() fails.
> 
> The DL BW freeing is handled in cpuset_cancel_attach() for the case
> `multiple controllers and one of the non-cpuset can_attach() fails`.
> 
> Only lightly tested on cgroup v1 with exclusive cpusets so far.

This makes sense to me. Thanks for working on it!

Guess I might incorporate these in my (RFC) series and re-post the whole
lot?

Best,
Juri