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Date:   Sun, 12 Jun 2022 23:04:14 -0400
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Subject: Re: [PATCH v11 3/8] cgroup/cpuset: Allow no-task partition to have
 empty cpuset.cpus.effective
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To:     Tejun Heo <tj@kernel.org>
Cc:     Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Shuah Khan <shuah@kernel.org>, cgroups@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kselftest@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Roman Gushchin <guro@fb.com>, Phil Auld <pauld@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>
References: <20220510153413.400020-1-longman@redhat.com>
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From:   Waiman Long <longman@redhat.com>
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On 6/12/22 22:55, Tejun Heo wrote:
> On Sun, Jun 12, 2022 at 10:53:53PM -0400, Waiman Long wrote:
>> Without this patch, cpus.effective will never be empty. It just falls back
>> to its parent if it becomes empty. Now with an empty cpus.effective, I am
> Yeah, that part is fine.
>
>> afraid that if a task is somehow moved to such a cpuset, something bad may
>> happen. So I add this check as a safeguard.
> But how would that happen? A lot of other things would break too if that
> were to happen.

I will perform further check to see if this check is necessary.

Thanks,
Longman