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Date:   Thu, 6 May 2021 22:17:22 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Jens Axboe <axboe@kernel.dk>,
        Pavel Begunkov <asml.silence@gmail.com>,
        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 09:08:50PM +0000, Al Viro wrote:
> On Thu, May 06, 2021 at 01:15:01PM -0600, Jens Axboe wrote:
> 
> > Attached output of perf annotate <func> for that last run.
> 
> Heh...  I wonder if keeping the value of iocb_flags(file) in
> struct file itself would have a visible effect...

I suggested that ...
https://lore.kernel.org/linux-fsdevel/20210110061321.GC35215@casper.infradead.org/