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Date: Fri, 22 Mar 2013 09:34:54 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>, Frederic Weisbecker <fweisbec@gmail.com>,
        Ming Lei <tom.leiming@gmail.com>, Shaohua Li <shli@kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: +
 atomic-improve-atomic_inc_unless_negative-atomic_dec_unless_positive .patch
 added to -mm tree
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On Thu, Mar 21, 2013 at 03:56:58PM -0700, Eric Dumazet wrote:
> On Thu, 2013-03-21 at 19:30 +0100, Oleg Nesterov wrote:
> 
> > To me, it would be better to kill atomic_inc_not_zero_hint() or unify
> > unify it with atomic_inc_not_zero(). But this is another story.
> 
> git is your friend.
> 
> I suggest you read 3f9d35b9514 changelog before killing it, thanks.

Hello, Eric,

Does the addition of a memory barrier in the not-zero case impose
too large a performance penalty?

							Thanx, Paul