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To: Don Lewis <truckman@FreeBSD.org>
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From: Brian Fundakowski Feldman <green@FreeBSD.org>
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Date: Thu, 13 May 2004 16:22:09 -0400
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Subject: Re: fifo / named pipe patch testers wanted 
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Don Lewis <truckman@FreeBSD.org> wrote:
> Using the vnode mutex in fifo_open() causes lock order problems when
> combined with some of the network stack locking changes that are in
> progress.  The patch below modifies fifo_open() to use a private mutex
> in place of the vnode mutex.  There is also some minor optimization of a
> couple of calls to fifo_cleanup().  This patch has passed my torture
> testing, but it could probably use some more testing by anyone who
> heavily uses named pipes, especially with select(), kqueue(), and SIGIO.
                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Major, major obstacles for fine-grained network stack locking changes in 
progress :-(  This barely scratches the surface of what seems to need to be 
fixed.

-- 
Brian Fundakowski Feldman                           \'[ FreeBSD ]''''''''''\
  <> green@FreeBSD.org                               \  The Power to Serve! \
 Opinions expressed are my own.                       \,,,,,,,,,,,,,,,,,,,,,,\