Date: Tue, 14 Aug 2007 15:51:23 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: Chris Snook <csnook@redhat.com>
cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
       torvalds@linux-foundation.org, netdev@vger.kernel.org,
       akpm@linux-foundation.org, ak@suse.de, heiko.carstens@de.ibm.com,
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       horms@verge.net.au, wjiang@resilience.com, cfriesen@nortel.com,
       zlynx@acm.org, rpjday@mindspring.com, jesper.juhl@gmail.com
Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
 architectures
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On Tue, 14 Aug 2007, Chris Snook wrote:

> But barriers force a flush of *everything* in scope, which we generally don't
> want.  On the other hand, we pretty much always want to flush atomic_*
> operations.  One way or another, we should be restricting the volatile
> behavior to the thing that needs it.  On most architectures, this patch set
> just moves that from the declaration, where it is considered harmful, to the
> use, where it is considered an occasional necessary evil.

Then we would need

	atomic_read()

and

	atomic_read_volatile()

atomic_read_volatile() would imply an object sized memory barrier before 
and after?
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