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Date:   Thu, 6 May 2021 17:17:28 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Pavel Begunkov <asml.silence@gmail.com>
Cc:     Jens Axboe <axboe@kernel.dk>, yangerkun <yangerkun@huawei.com>,
        linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
        io-uring@vger.kernel.org
Subject: Re: [PATCH] block: reexpand iov_iter after read/write
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On Thu, May 06, 2021 at 05:57:02PM +0100, Pavel Begunkov wrote:
> On 4/30/21 3:35 PM, Al Viro wrote:
> > On Fri, Apr 30, 2021 at 01:57:22PM +0100, Pavel Begunkov wrote:
> >> On 4/28/21 7:16 AM, yangerkun wrote:
> >>> Hi,
> >>>
> >>> Should we pick this patch for 5.13?
> >>
> >> Looks ok to me
> > 
> > 	Looks sane.  BTW, Pavel, could you go over #untested.iov_iter
> > and give it some beating?  Ideally - with per-commit profiling to see
> > what speedups/slowdowns do they come with...
> 
> I've heard Jens already tested it out. Jens, is that right? Can you
> share? especially since you have much more fitting hardware.

FWIW, the current branch is #untested.iov_iter-3 and the code generated
by it at least _looks_ better than with mainline; how much of an improvement
does it make would have to be found by profiling...