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;
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>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Hao Luo <haoluo@google.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-kernel@vger.kernel.org, luca.abeni@santannapisa.it,
        claudio@evidence.eu.com, tommaso.cucinotta@santannapisa.it,
        bristot@redhat.com, mathieu.poirier@linaro.org,
        cgroups@vger.kernel.org,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Wei Wang <wvw@google.com>, Rick Yiu <rickyiu@google.com>,
        Quentin Perret <qperret@google.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        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>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20230503072228.115707-3-juri.lelli@redhat.com>
Precedence: bulk

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?