Date:   Mon, 20 Feb 2023 13:09:44 -0800
From:   Roman Gushchin <roman.gushchin@linux.dev>
To:     Yue Zhao <findns94@gmail.com>
Cc:     linux-mm@kvack.org, akpm@linux-foundation.org, hannes@cmpxchg.org,
        mhocko@kernel.org, shakeelb@google.com, muchun.song@linux.dev,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: change memcg->oom_group access with atomic operations
Message-ID: <Y/PhmEPc/qYeZ52T@P9FQF9L96D>
References: <20230220151638.1371-1-findns94@gmail.com>
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On Mon, Feb 20, 2023 at 11:16:38PM +0800, Yue Zhao wrote:
> The knob for cgroup v2 memory controller: memory.oom.group
> will be read and written simultaneously by user space
> programs, thus we'd better change memcg->oom_group access
> with atomic operations to avoid concurrency problems.
> 
> Signed-off-by: Yue Zhao <findns94@gmail.com>

Hi Yue!

I'm curious, have any seen any real issues which your patch is solving?
Can you, please, provide a bit more details.

Also, WRITE/READ_ONCE() don't generally make operations atomic,
they only prevent the compiler from merging and re-fetching reads
and writes.

Thanks!