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Sender: Tejun Heo <htejun@gmail.com>
Date:   Sun, 12 Jun 2022 07:41:13 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Jonathan Corbet <corbet@lwn.net>,
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        Andrew Morton <akpm@linux-foundation.org>,
        Roman Gushchin <guro@fb.com>, Phil Auld <pauld@redhat.com>,
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        Juri Lelli <juri.lelli@redhat.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
Subject: Re: [PATCH v11 3/8] cgroup/cpuset: Allow no-task partition to have
 empty cpuset.cpus.effective
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On Sun, Jun 12, 2022 at 07:40:25AM -1000, Tejun Heo wrote:
> Hello,
> 
> Sorry about the long delay.
> 
> On Tue, May 10, 2022 at 11:34:08AM -0400, Waiman Long wrote:
> > Once a partition with empty "cpuset.cpus.effective" is formed, no
> > new task can be moved into it until "cpuset.cpus.effective" becomes
> > non-empty.
> 
> This is always true due to no-tasks-in-intermediate-cgroups requirement,
> right?

or rather, I should have asked, why does this need an explicit check?

Thanks.

-- 
tejun