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Date: Sun, 18 Dec 2016 22:18:53 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>,
        Dave Chinner <david@fromorbit.com>,
        CAI Qian <caiqian@redhat.com>,
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Subject: Re: [PATCH 04/12] splice: lift pipe_lock out of splice_to_pipe()
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On Sun, Dec 18, 2016 at 02:10:54PM -0800, Linus Torvalds wrote:
> On Sun, Dec 18, 2016 at 12:30 PM, Al Viro <viro@zeniv.linux.org.uk> wrote:
> >
> > OK, I see what's going on - it's wait_for_space() lifted past the checks
> > for lack of readers.  The fix, AFAICS, is simply
> 
> Ugh. Does it have to be duplicated?
> 
> How about just making the wait_for_space() loop be a for-loop, and writing it as
> 
>    for (;;) {
>         if (unlikely(!pipe->readers)) {
>                 send_sig(SIGPIPE, current, 0);
>                 return -EPIPE;
>         }
>         if (pipe->nrbufs == pipe->buffers)

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