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Date:   Mon, 13 Jun 2022 09:18:55 -0400
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Subject: Re: [PATCH v11 7/8] cgroup/cpuset: Update description of
 cpuset.cpus.partition in cgroup-v2.rst
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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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 <404171dc-0da3-21f2-5003-9718f875e967@redhat.com>
 <YqarMyNo9oHxhZFh@slm.duckdns.org>
From:   Waiman Long <longman@redhat.com>
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On 6/12/22 23:12, Tejun Heo wrote:
> Hello,
>
> On Sun, Jun 12, 2022 at 11:02:38PM -0400, Waiman Long wrote:
>> That is the behavior enforced by setting the CPU_EXCLUSIVE bit in cgroup v1.
>> I haven't explicitly change it to make it different in cgroup v2. The major
>> reason is that I don't want change to one cpuset to affect a sibling
>> partition as it may make the code more complicate to validate if a partition
>> is valid.
> If at all possible, I'd really like to avoid situations where a parent can't
> withdraw resources due to something that a descendant does.

No, it doesn't affect parent at all. It just limit whats the siblings 
can do due to their mutual constraint. If this is what the confusion is 
about, I will try to reword the doc text.

Cheers,
Longman