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[Xen-devel] Re: [PATCH]Further release shadow lock overhead

To: "Tian, Kevin" <kevin.tian@xxxxxxxxx>
Subject: [Xen-devel] Re: [PATCH]Further release shadow lock overhead
From: Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Date: Tue, 22 Jan 2008 09:36:50 +0000
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Hi,

At 14:10 +0800 on 22 Jan (1201011038), Tian, Kevin wrote:
>       Please take a look whether this optimization is
> feasible. :-)

It goes just a little bit too far. :)  The shadow lock must be taken
before the guest pagetable is modified and not released until after the
shadow has been modified to match it.

It might be possible to delay taking the lock until after the guest walk
and the mappings are done, but I'm not sure of it.

Cheers,

Tim.

-- 
Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Principal Software Engineer, Citrix Systems (R&D) Ltd.
[Company #02300071, SL9 0DZ, UK.]

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