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Date:   Wed, 24 May 2023 10:02:18 +0200
From:   Michal =?utf-8?Q?Koutn=C3=BD?= <mkoutny@suse.com>
To:     Hao Jia <jiahao.os@bytedance.com>
Cc:     tj@kernel.org, lizefan.x@bytedance.com, hannes@cmpxchg.org,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [External] Re: [PATCH] cgroup: rstat: Simplified
 cgroup_base_stat_flush() update last_bstat logic
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On Wed, May 24, 2023 at 02:54:10PM +0800, Hao Jia <jiahao.os@bytedance.com> wrote:
> Yes, so we need @curr to record the bstat value after the sequence fetch is
> completed.

No, I still don't see a problem that it solves. If you find incorrect
data being reported, please explain it more/with an example.

> Yes, but it may not be obvious.
> Another reason is that when we complete an update, we snapshot last_bstat as
> the current bstat, which is better for readers to understand. Arithmetics is
> somewhat obscure.

The readability here is subjective. It'd be interesting to have some
data comparing arithmetics vs copying though.

HTH,
Michal

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