From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: on memory barriers and cachelines
Date: Wed, 01 Feb 2012 18:29:16 +0100
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To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, benh <benh@kernel.crashing.org>, davem <davem@davemloft.net>, "H. Peter Anvin" <hpa@zytor.com>, Linux-Arch <linux-arch@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>, dhowells <dhowells@redhat.com>

On Wed, 2012-02-01 at 09:17 -0800, Linus Torvalds wrote:
> 
> Also, even if you were to find an atomic sub-chunk, if you need a
> "smp_rmb()", what else would guarantee that the CPU core wouldn't
> re-order things to do the second read first, then lose the cacheline,
> re-read it, and then do the first read? 

Fair enough.. Thanks!