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Sender: Tejun Heo <htejun@gmail.com>
Date:   Mon, 26 Jun 2023 10:46:15 -1000
From:   Tejun Heo <tj@kernel.org>
To:     chengming.zhou@linux.dev
Cc:     axboe@kernel.dk, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, zhouchengming@bytedance.com
Subject: Re: [PATCH v2 3/3] blk-mq: fix start_time_ns and alloc_time_ns for
 pre-allocated rq
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 <20230626050405.781253-4-chengming.zhou@linux.dev>
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Hello,

I only glanced the blk-mq core part but in general this looks a lot better
than the previous one.

On Mon, Jun 26, 2023 at 01:04:05PM +0800, chengming.zhou@linux.dev wrote:
> Note we don't skip setting alloc_time_ns and start_time_ns for all
> pre-allocated rq, since the first returned rq still need to be set.

This part is a bit curious for me tho. Why do we need to set it at batch
allocation time and then at actual dispensing from the bat later? Who uses
the alloc time stamp inbetween?

Thanks.

-- 
tejun