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Message-ID: <6d5aee58-f558-868c-76e0-0b58f8332110@redhat.com>
Date:   Mon, 10 Jul 2023 20:21:43 -0400
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Subject: Re: [PATCH v4 8/9] cgroup/cpuset: Documentation update for partition
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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>, linux-kernel@vger.kernel.org,
        cgroups@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kselftest@vger.kernel.org,
        Juri Lelli <juri.lelli@redhat.com>,
        Valentin Schneider <vschneid@redhat.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Mrunal Patel <mpatel@redhat.com>,
        Ryan Phillips <rphillips@redhat.com>,
        Brent Rowsell <browsell@redhat.com>,
        Peter Hunt <pehunt@redhat.com>, Phil Auld <pauld@redhat.com>
References: <20230627143508.1576882-1-longman@redhat.com>
 <20230627143508.1576882-9-longman@redhat.com>
 <ZKx4ZJowRhRtjZxB@slm.duckdns.org>
From:   Waiman Long <longman@redhat.com>
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On 7/10/23 17:30, Tejun Heo wrote:
> Hello,
>
> On Tue, Jun 27, 2023 at 10:35:07AM -0400, Waiman Long wrote:
> ...
>> +	There are two types of partitions - local and remote.  A local
>> +	partition is one whose parent cgroup is also a valid partition
>> +	root.  A remote partition is one whose parent cgroup is not a
>> +	valid partition root itself.  Writing to "cpuset.cpus.exclusive"
>> +	is not mandatory for the creation of a local partition as its
>> +	"cpuset.cpus.exclusive" file will be filled in automatically if
>> +	it is not set.	The automaticaly set value will be based on its
>> +	"cpuset.cpus" value.  Writing the proper "cpuset.cpus.exclusive"
>> +	values down the cgroup hierarchy is mandatory for the creation
>> +	of a remote partition.
> Wouldn't a partition root's cpus.exclusive always contain all of the CPUs in
> its cpus? Would it make sense for cpus.exclusive to be different from .cpus?
>
> Thanks.

In auto-filled case, it should be the same as cpuset.cpus. I will 
clarify that in the documentation. Thanks for catching that.

Cheers,
Longman