| Date | Thu, 19 Dec 2013 22:17:01 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH] x86 idle: repair large-server 50-watt idle-power regression |
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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
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