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Date: Mon, 06 Jul 2009 14:36:55 -0700
From: john.gregor@qlogic.com (John A. Gregor)
To: hpa@zytor.com
Subject: Re: [PATCH] x86_64/__iowrite32_copy: don't use string move for PIO
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       johng@diamond.mv.qlogic.com
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"H. Peter Anvin" <hpa@zytor.com> wrote:

> 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*?

Nehalem.

-John Gregor