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Date: Wed, 15 Aug 2007 19:17:10 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
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On Wed, 15 Aug 2007, Christoph Lameter wrote:

> On Thu, 16 Aug 2007, Paul Mackerras wrote:
> 
> > > We don't need to reload sk->sk_prot->memory_allocated here.
> > 
> > Are you sure?  How do you know some other CPU hasn't changed the value
> > in between?
> 
> The cpu knows because the cacheline was not invalidated.

Crap my statement above is wrong..... We do not care that the 
value was changed otherwise we would have put a barrier in there.