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Date:   Thu, 4 May 2023 08:21:05 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Juri Lelli <juri.lelli@redhat.com>
Cc:     Ingo Molnar <mingo@kernel.org>, Qais Yousef <qyousef@layalina.io>,
        Waiman Long <longman@redhat.com>, Tejun Heo <tj@kernel.org>,
        Zefan Li <lizefan.x@bytedance.com>,
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        Vincent Guittot <vincent.guittot@linaro.org>,
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        Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Sudeep Holla <sudeep.holla@arm.com>
Subject: Re: [PATCH v2 2/6] sched/cpuset: Bring back cpuset_mutex
Message-ID: <20230504062105.GD1734100@hirez.programming.kicks-ass.net>
References: <20230503072228.115707-1-juri.lelli@redhat.com>
 <20230503072228.115707-3-juri.lelli@redhat.com>
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On Wed, May 03, 2023 at 09:22:24AM +0200, Juri Lelli wrote:
> Turns out percpu_cpuset_rwsem - commit 1243dc518c9d ("cgroup/cpuset:
> Convert cpuset_mutex to percpu_rwsem") - wasn't such a brilliant idea,
> as it has been reported to cause slowdowns in workloads that need to
> change cpuset configuration frequently and it is also not implementing
> priority inheritance (which causes troubles with realtime workloads).

What were they doing ? Dynamically adjusting the DL parameters?