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Date: Tue, 3 Dec 2002 10:42:13 -0500 (EST)
From: "Calin A. Culianu" <calin@ajvar.org>
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To: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: SMP Pentium4 -- PAUSE Instruction
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I as wondering -- according to Intel's docs they recommend that on a P4
processor to use the PAUSE instruction (aka rep followed by a nop) inside
any spin loop (such as one used in SMP spinlock code) in order to both
improve processor performance and reduce power consumption.

Is this instruction being used in spin-wait loops?  For some reason, I am
having a hard time figuring out whether or not it is being used.  There is
a rep_nop() in processor.h.. but I can't determine if that is being called
for spin lock lock/unlock code.


-Calin


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