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Date:   Fri, 16 Nov 2018 14:59:22 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Omar Sandoval <osandov@osandov.com>
Cc:     Ming Lei <ming.lei@redhat.com>, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, Dave Chinner <dchinner@redhat.com>,
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Subject: Re: [PATCH V10 18/19] block: kill QUEUE_FLAG_NO_SG_MERGE
Message-ID: <20181116135922.GO3165@lst.de>
References: <20181115085306.9910-1-ming.lei@redhat.com> <20181115085306.9910-19-ming.lei@redhat.com> <20181116021811.GM23828@vader>
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On Thu, Nov 15, 2018 at 06:18:11PM -0800, Omar Sandoval wrote:
> This commit message wasn't very clear. Is it the case that
> QUEUE_FLAG_NO_SG_MERGE is no longer set by any drivers?

I think he wants to say that not doing S/G merging is rather pointless
with the current setup of the I/O path, as it isn't going to save
you a significant amount of cycles.