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From:   Muchun Song <songmuchun@bytedance.com>
Date:   Thu, 11 May 2023 14:38:00 +0800
Message-ID: <CAMZfGtV8FUoBzhPjFu8V5=e=dQ3wRm+qK7S0HHCB22cjKDLAdQ@mail.gmail.com>
Subject: Re: [PATCH v3] blk-throttle: Fix io statistics for cgroup v1
To:     Jinke Han <hanjinke.666@bytedance.com>
Cc:     tj@kernel.org, josef@toxicpanda.com, axboe@kernel.dk,
        cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, andrea.righi@canonical.com
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On Mon, May 8, 2023 at 1:07=E2=80=AFAM Jinke Han <hanjinke.666@bytedance.co=
m> wrote:
>
> From: Jinke Han <hanjinke.666@bytedance.com>
>
> After commit f382fb0bcef4 ("block: remove legacy IO schedulers"),
> blkio.throttle.io_serviced and blkio.throttle.io_service_bytes become
> the only stable io stats interface of cgroup v1, and these statistics
> are done in the blk-throttle code. But the current code only counts the
> bios that are actually throttled. When the user does not add the throttle
> limit, the io stats for cgroup v1 has nothing. I fix it according to the
> statistical method of v2, and made it count all ios accurately.
>
> Fixes: a7b36ee6ba29 ("block: move blk-throtl fast path inline")
> Tested-by: Andrea Righi <andrea.righi@canonical.com>
> Signed-off-by: Jinke Han <hanjinke.666@bytedance.com>

Good catch.

Acked-by: Muchun Song <songmuchun@bytedance.com>

Thanks.