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Subject: Re: [PATCH] 2.6 workaround for Athlon/Opteron prefetch errata
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Bill Davidsen <davidsen@tmr.com>
Cc: Zwane Mwaikambo <zwane@linuxpower.ca>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Date: Mon, 15 Sep 2003 08:45:59 +0100
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On Llu, 2003-09-15 at 04:55, Bill Davidsen wrote:
> 1 - the code is not needed for Athlon, prefetch is turned off on broken
>     CPUs now. A generic kernel runs fine on Athlon.

That disable you talk about is bloat. It also trashes the performance of
PIV boxes. In fact I checked out of interest - the disable hack
currently being used is adding *over* 300 bytes to my kernel as its
inlined repeatedly. So its larger, and it ruins performance for all
processors.

You also need it for userspace prefetch fault fixup for a kernel without
CONFIG_MK7 to run stuff perfectly on Athlon.