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Date:   Mon, 17 Aug 2020 20:06:54 +0800
From:   Baolin Wang <baolin.wang@linux.alibaba.com>
To:     Christoph Hellwig <hch@lst.de>
Cc:     axboe@kernel.dk, ming.lei@redhat.com, baolin.wang7@gmail.com,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND 2/5] block: Remove redundant
 blk_mq_sched_allow_merge() validation
Message-ID: <20200817120654.GA79836@VM20190228-100.tbsite.net>
Reply-To: Baolin Wang <baolin.wang@linux.alibaba.com>
References: <cover.1597637287.git.baolin.wang@linux.alibaba.com>
 <b9d51f4bc9f0ff4ec3b8fb7fa6dc366afd69290e.1597637287.git.baolin.wang@linux.alibaba.com>
 <20200817062224.GB12248@lst.de>
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On Mon, Aug 17, 2020 at 08:22:24AM +0200, Christoph Hellwig wrote:
> On Mon, Aug 17, 2020 at 12:09:16PM +0800, Baolin Wang wrote:
> > Only software queue and kyber IO scheduler will call blk_mq_bio_list_merge()
> > to merge a bio, and kyber IO scheduler did not implement the ops->allow_merge().
> 
> Please line wrap your changelogs after 73 characters.

Sure.

> 
> > Thus we can remove the redundant blk_mq_sched_allow_merge() in
> > blk_mq_bio_list_merge() function.
> 
> This seems potentially dangerous, and I don't think it really buys
> us much.

OK. I can remove this in next version.