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Date:   Fri, 28 Apr 2023 12:22:16 +0100
From:   Qais Yousef <qyousef@layalina.io>
To:     Juri Lelli <juri.lelli@redhat.com>
Cc:     Xuewen Yan <xuewen.yan94@gmail.com>,
        Waiman Long <longman@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>, 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>,
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Subject: Re: [PATCH 2/6] sched/cpuset: Bring back cpuset_mutex
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On 04/27/23 07:53, Juri Lelli wrote:
> Hi,
> 
> On 27/04/23 10:58, Xuewen Yan wrote:
> > HI Juri,
> > 
> > Would this patch be merged tobe stable-rc? In kernel5.15, we also find
> > that the rwsem would be blocked for a long  time, when we change the
> > task's cpuset cgroup.
> > And when we revert to the mutex, the delay would disappear.
> 
> Honestly, I'm not sure. This change is mostly improving performance, but
> it is also true that it's fixing some priority inheritance corner cases.
> So, I'm not sure it qualifies for stable, but it would be probably good to
> have it there.

I'm under the impression we need the whole lot back to stable, no? I'm not sure
if we can decouple this patch from the rest.

FWIW, I did my testing on 5.15 - so we can definitely help with the backport
and testing for 5.15 and 5.10.


Thanks!

--
Qais Yousef