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Date:   Fri, 7 Jul 2023 18:06:30 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     chengming.zhou@linux.dev
Cc:     axboe@kernel.dk, hch@lst.de, tj@kernel.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        zhouchengming@bytedance.com
Subject: Re: [PATCH v3 4/4] blk-flush: reuse rq queuelist in flush state
 machine
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References: <20230707093722.1338589-1-chengming.zhou@linux.dev>
 <20230707093722.1338589-5-chengming.zhou@linux.dev>
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On Fri, Jul 07, 2023 at 05:37:22PM +0800, chengming.zhou@linux.dev wrote:
> From: Chengming Zhou <zhouchengming@bytedance.com>
> 
> Since we don't need to maintain inflight flush_data requests list
> anymore, we can reuse rq->queuelist for flush pending list.
> 
> Note in mq_flush_data_end_io(), we need to re-initialize rq->queuelist
> before reusing it in the state machine when end, since the rq->rq_next
> also reuse it, may have corrupted rq->queuelist by the driver.
> 
> This patch decrease the size of struct request by 16 bytes.
> 
> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> ---
> v3:
>  - fix a bug report of blktests nvme/012, we need to re-initialize
>    rq->queuelist before reusing it in the state machine when end.
>    Because rq->rq_next reuse may have corrupted it. Thanks Ming Lei.

Reviewed-by: Ming Lei <ming.lei@redhat.com>

Thanks,
Ming