Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Sender: Tejun Heo <htejun@gmail.com>
Date:   Thu, 12 May 2022 16:58:22 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Josh Don <joshdon@google.com>
Cc:     Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Valentin Schneider <vschneid@redhat.com>,
        linux-kernel@vger.kernel.org,
        Cruz Zhao <CruzZhao@linux.alibaba.com>
Subject: Re: [PATCH] sched/core: add forced idle accounting for cgroups
Message-ID: <Yn3JTpXhWRTeahyG@slm.duckdns.org>
References: <20220513005427.2507335-1-joshdon@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20220513005427.2507335-1-joshdon@google.com>
Precedence: bulk

On Thu, May 12, 2022 at 05:54:27PM -0700, Josh Don wrote:
> 4feee7d1260 previously added per-task forced idle accounting. This patch
> extends this to also include cgroups.
> 
> rstat is used for cgroup accounting, except for the root, which uses
> kcpustat in order to bypass the need for doing an rstat flush when
> reading root stats.
> 
> Only cgroup v2 is supported. Similar to the task accounting, the cgroup
> accounting requires that schedstats is enabled.

We've been collecting scheduler stats in cgroup core so that we always have
them available whether cpu controller is enabled or not. There's nothing
actually specific to cpu controller, right? Would it make sense to collect
the cpu core stats the same way as the rest of scheduler stats?

Thanks.

-- 
tejun