From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH] x86 idle: repair large-server 50-watt idle-power
 regression
Date: Thu, 19 Dec 2013 22:17:01 +0100
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To: "H. Peter Anvin" <hpa@zytor.com>
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* H. Peter Anvin <hpa@zytor.com> wrote:

> CLFLUSH is only (guaranteed to be) ordered with respect to MFENCE 
> according to the SDM.

Yes, I quoted the relevant text a couple of hours ago, CLFLUSH is 
pretty special, so it's not ordered against atomics or serializing 
instructions for example - only ordered against explict MFENCE calls, 
which on x86 is mb()/smp_mb().

Thanks,

	Ingo