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Date: Fri, 17 Aug 2007 12:16:39 +1000
From: Paul Mackerras <paulus@samba.org>
To: Christoph Lameter <clameter@sgi.com>
Cc: Chris Snook <csnook@redhat.com>,
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Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
 architectures
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Christoph Lameter writes:

> No it does not have any volatile semantics. atomic_dec() can be reordered 
> at will by the compiler within the current basic unit if you do not add a 
> barrier.

Volatile doesn't mean it can't be reordered; volatile means the
accesses can't be eliminated.

Paul.
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