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Date:   Wed, 27 Sep 2023 16:40:50 +0530
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Subject: Re: [External] : [PATH v3] cgroup: add cgroup_favordynmods=
 command-line option
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To:     Luiz Capitulino <luizcap@amazon.com>, tj@kernel.org,
        lizefan.x@bytedance.com, hannes@cmpxchg.org,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
        longman@redhat.com, mkoutny@suse.com
Cc:     lcapitulino@gmail.com
References: <20230926211617.42746-1-luizcap@amazon.com>
From:   Kamalesh Babulal <kamalesh.babulal@oracle.com>
In-Reply-To: <20230926211617.42746-1-luizcap@amazon.com>
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On 9/27/23 02:46, Luiz Capitulino wrote:
> We have a need of using favordynmods with cgroup v1, which doesn't support
> changing mount flags during remount. Enabling CONFIG_CGROUP_FAVOR_DYNMODS at
> build-time is not an option because we want to be able to selectively
> enable it for certain systems.
> 
> This commit addresses this by introducing the cgroup_favordynmods=
> command-line option. This option works for both cgroup v1 and v2 and also
> allows for disabling favorynmods when the kernel built with
> CONFIG_CGROUP_FAVOR_DYNMODS=y.
> 
> Also, note that when cgroup_favordynmods=true favordynmods is never
> disabled in cgroup_destroy_root().
> 
> Signed-off-by: Luiz Capitulino <luizcap@amazon.com>

The patch looks good to me, I have also boot tested it with combinations of
CONFIG_CGROUP_FAVOR_DYNMODS={y, n}, while passing the kernel parameter
cgroup_favordynmods={true, false} to the command line and works as expected.

Reviewed-by: Kamalesh Babulal <kamalesh.babulal@oracle.com>