From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [RFC] get_write_access()/deny_write_access() without
 inode->i_lock
Date: Mon, 20 Jun 2011 18:03:05 +0100
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On Mon, Jun 20, 2011 at 05:42:11PM +0100, Al Viro wrote:

> BTW, atomic_add_unless/atomic_inc_not_zero is done as read/cmpxchg on
> everything I've checked, including alpha and sparc.  I suspect that
> it's seriously suboptimal there...

Actually, on sparc it's probably fine.  alpha, OTOH, probably ought to switch
to something similar to what ppc is doing...