From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: [PATCH] x86: add SSE-based copy_page()
Date: Tue, 13 Jan 2009 08:34:07 +0000
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	<C591FDA7.20EC9%keir.fraser@eu.citrix.com>
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To: Keir Fraser <keir.fraser@eu.citrix.com>, Dexuan Cui <dexuan.cui@intel.com>, Dan Magenheimer <dan.magenheimer@oracle.com>
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>>> Keir Fraser <keir.fraser@eu.citrix.com> 13.01.09 09:13 >>>
>Seems like unless we dynamically choose the copy routine, we're better =
off
>without the SSE2 alternative. Shall I revert it then?

I'd vote for not reverting it - Xen itself doesn't use copy_page() much, =
and
whether a domain wants to use MMUEXT_COPY_PAGE could be decided by
it based on its own judgement.

Ultimately we should improve it as you say to dynamically select the copy
method, but then the question really is whether to base the selection on
static CPU information, best cold, or best warm cache performance.

Jan