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Subject: Re: [PATCH] cpuset: Allow v2 behavior in v1 cgroup
To: Waiman Long <longman@redhat.com>, Tejun Heo <tj@kernel.org>,
        "Johannes Weiner" <hannes@cmpxchg.org>,
        Jonathan Corbet <corbet@lwn.net>
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From: Zefan Li <lizefan@huawei.com>
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Date: Wed, 16 Aug 2017 09:20:27 +0800
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On 2017/8/16 1:27, Waiman Long wrote:
> Cpuset v2 has some valuable attributes that are not present in
> v1 because of backward compatibility concern. One of that is the
> restoration of the original cpu and memory node mask after a hot
> removal and addition event sequence.
> 
> This patch adds a new kernel command line option "cpuset_v2_mode=" to
> allow cpuset to have v2 behavior in a v1 cgroup when using a non-zero
> value. This enables users to optionally enable cpuset v2 behavior if
> they choose to.
> 
> Signed-off-by: Waiman Long <longman@redhat.com>

I have no strong objection. I have received quite a few requests for
this in the past, and some were from other departments in my company.