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Date: Mon, 27 Jun 2005 22:08:27 -0700 (PDT)
Message-Id: <20050627.220827.21920197.davem@davemloft.net>
To: nickpiggin@yahoo.com.au
Cc: wli@holomorphy.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [patch 2] mm: speculative get_page
From: "David S. Miller" <davem@davemloft.net>
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From: Nick Piggin <nickpiggin@yahoo.com.au>
Subject: Re: [patch 2] mm: speculative get_page
Date: Tue, 28 Jun 2005 14:50:31 +1000

> William Lee Irwin III wrote:
> 
> >On Tue, Jun 28, 2005 at 11:42:16AM +1000, Nick Piggin wrote:
> >
> >spin_unlock() does not imply a memory barrier.
> >
> 
> Intriguing...

BTW, I disagree with this assertion.  spin_unlock() does imply a
memory barrier.

All memory operations before the release of the lock must execute
before the lock release memory operation is globally visible.