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Date: Mon, 06 Jul 2009 14:30:14 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: John Gregor <john.gregor@qlogic.com>
CC: linux-kernel@vger.kernel.org, John Gregor <johng@diamond.mv.qlogic.com>,
       Ralph Campbell <ralph.campbell@qlogic.com>
Subject: Re: [PATCH] x86_64/__iowrite32_copy: don't use string move for PIO
 writes
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John Gregor wrote:
> From: John Gregor <johng@diamond.mv.qlogic.com>
> 
> Some processors can write the same word more than once if the movs
> instruction is used. This version uses normal memory move instructions
> and gets the same performance since the speed is limited by PCIe and
> write combining.
> 

Which processors do that *when addressing I/O memory*?

	-hpa