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Date:   Mon, 21 Aug 2023 14:26:28 -0700
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Subject: Re: [PATCH 2/4] blk-mq-tag: remove bt_for_each()
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To:     chengming.zhou@linux.dev, axboe@kernel.dk, ming.lei@redhat.com,
        hch@lst.de
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        zhouchengming@bytedance.com
References: <20230821073528.3469210-1-chengming.zhou@linux.dev>
 <20230821073528.3469210-3-chengming.zhou@linux.dev>
From:   Bart Van Assche <bvanassche@acm.org>
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On 8/21/23 00:35, chengming.zhou@linux.dev wrote:
> 2. __blk_mq_tagset_busy_iter() has BT_TAG_ITER_STARTED flag set, so only
>     started requests will be iterated, which should be more efficient.

The above motivation sounds wrong to me. The goal here should be not to
change the behavior of blk_mq_queue_tag_busy_iter(). Although
blk_mq_queue_tag_busy_iter() iterates over more requests than only started
requests, apparently blk_mq_queue_tag_busy_iter() is only used to iterate
over started requests (blk_mq_request_started()). Please mention this in
the patch description.

Thanks,

Bart.