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Date: Tue, 10 Sep 2024 17:48:43 +0200
From: Christoph Hellwig <hch@lst.de>
To: Keith Busch <kbusch@meta.com>
Cc: axboe@kernel.dk, hch@lst.de, martin.petersen@oracle.com,
	linux-block@vger.kernel.org, linux-nvme@lists.infradead.org,
	linux-scsi@vger.kernel.org, sagi@grimberg.me,
	Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCHv3 09/10] blk-integrity: consider entire bio list for
 merging
Message-ID: <20240910154843.GI23805@lst.de>
References: <20240904152605.4055570-1-kbusch@meta.com> <20240904152605.4055570-10-kbusch@meta.com>
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On Wed, Sep 04, 2024 at 08:26:04AM -0700, Keith Busch wrote:
> From: Keith Busch <kbusch@kernel.org>
> 
> If a bio is merged to a req, the entire bio list is merged, so don't
> temporarily unchain it when counting segments for consideration.

As far as I can tell we never do merge decisions on bio lists.  If
bi_next is non-NULL here it probably is due to scheduler lists or
something like it.