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Subject: Re: [PATCH v7 5/6] cgroup/cpuset: Update description of
 cpuset.cpus.partition in cgroup-v2.rst
From:   Waiman Long <longman@redhat.com>
To:     =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>,
        Waiman Long <llong@redhat.com>
Cc:     Tejun Heo <tj@kernel.org>, 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>
References: <20210825213750.6933-1-longman@redhat.com>
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Message-ID: <306d7fca-ee8a-e5dc-973e-5255d73de71f@redhat.com>
Date:   Wed, 13 Oct 2021 18:11:37 -0400
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On 10/13/21 5:45 PM, Waiman Long wrote:
>
>
>>
>> In conclusion, it'd be good to have validity conditions separate from
>> transition conditions (since hotplug transition can't be rejected) and
>> perhaps treat administrative changes from an ancestor equally as a
>> hotplug.
>
> I am trying to make the result of changing "cpuset.cpus" as close to 
> hotplug as possible but there are cases where the "cpuset.cpus" change 
> is prohibited but hotplug can still happen to remove the cpu.
>
> Hope this will help to clarify the current design.
>
BTW, the attached file is the current draft of cpuset.cpus.partition 
document.

Cheers,
Longman


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