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Date: Wed, 15 Aug 2007 17:42:07 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
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Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
 architectures
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On Wed, 15 Aug 2007, Paul E. McKenney wrote:

> Seems to me that we face greater chance of confusion without the
> volatile than with, particularly as compiler optimizations become
> more aggressive.  Yes, we could simply disable optimization, but
> optimization can be quite helpful.

A volatile default would disable optimizations for atomic_read. 
atomic_read without volatile would allow for full optimization by the 
compiler. Seems that this is what one wants in many cases.

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