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Date: Tue, 10 Apr 2007 22:18:49 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: kenchen@google.com (Ken Chen)
Cc: linux-aio@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [patch] convert aio event reap to use atomic-op instead of
 spin_lock
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On Tue, 10 Apr 2007 16:53:53 -0700 (PDT) kenchen@google.com (Ken Chen) wrote:

> +	} while (head != cmpxchg(&ring->head, head, head + 1));

A hasty grep indicates that only 14 out of 23 architectures implement
cmpxchg().