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Subject: Re: [PATCH] target/file: don't zero iter before iov_iter_bvec
To:     Pavel Begunkov <asml.silence@gmail.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>
Cc:     linux-scsi@vger.kernel.org, target-devel@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <34cd22d6cec046e3adf402accb1453cc255b9042.1610207523.git.asml.silence@gmail.com>
From:   Bart Van Assche <bvanassche@acm.org>
Message-ID: <488fa4ff-3e08-28cc-60f1-b8c5172e1f79@acm.org>
Date:   Sun, 10 Jan 2021 18:49:11 -0800
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On 1/9/21 7:53 AM, Pavel Begunkov wrote:
> iov_iter_bvec() initialises iterators well, no need to pre-zero it
> beforehand as done in fd_execute_rw_aio(). Compilers can't optimise it
> out and generate extra code for that (confirmed with assembly).

Reviewed-by: Bart Van Assche <bvanassche@acm.org>