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Sender: Tejun Heo <htejun@gmail.com>
Date:   Thu, 5 Aug 2021 07:13:06 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Josh Don <joshdon@google.com>, Ingo Molnar <mingo@redhat.com>,
        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>,
        Paul Turner <pjt@google.com>,
        Oleg Rombakh <olegrom@google.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Steve Sistare <steven.sistare@oracle.com>,
        Rik van Riel <riel@surriel.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] sched: cgroup SCHED_IDLE support
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Hello,

On Thu, Aug 05, 2021 at 12:18:49PM +0200, Peter Zijlstra wrote:
> So I'm tempted to apply this, but last time TJ wasn't liking it much for
> the interface or somesuch. His argument that this encodes the
> hierarchical scheduling behaviour, but I'm not really buying that
> argument, as it doesn't really add more constraints than we already have
> by the hierarchical relative weight.

Interface-wise, writing 1 to idle file is fine. This does move away
the interface from being a purely semantical weight tree, which is a
concern and I have a difficult time seeing that the stated benefits
are significant enough to justify the changes. That said, this is
primarily a scheduler decision, so if you think the addition is
justified, please go ahead.

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun