From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gerd Hoffmann <kraxel@suse.de>
Subject: Re: CONFIG_XEN_COMPAT_030002 broken?
Date: Mon, 13 Nov 2006 18:08:19 +0100
Message-ID: <4558A683.30500@suse.de>
References: <C17E543E.46EC%keir@xensource.com>
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To: Keir Fraser <keir@xensource.com>
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Keir Fraser wrote:
> 
> Yes, and to allow fewer TLB entries to be flushed when switching between
> guest kernel and guest user. That optimisation is foiled if PAGE_USER is set
> everywhere.

Ok, so the extra cost to decide that at runtime (if
CONFIG_XEN_COMPAT_030002 is set) probably is outweighed by the tlb flush
optimization ...

cheers,
  Gerd

-- 
Gerd Hoffmann <kraxel@suse.de>
http://www.suse.de/~kraxel/julika-dora.jpeg