[Xen-devel] [PATCH] Shadow dirty-VRAM: avoid multiple remove_all

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Subject:	[Xen-devel] [PATCH] Shadow dirty-VRAM: avoid multiple remove_all_mappings calls.
From:	Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Date:	Fri, 23 Oct 2009 11:19:07 +0100
Delivery-date:	Fri, 23 Oct 2009 03:19:29 -0700
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sh_remove_all_mappings() will walk roughly half of the shadow L1 tables
for each MFN it's called with; calling it for every MFN in a guest's
framebuffer can be _very_ expensive, especially with the shadow lock
held across the whole operation.  Avoid that by just blowing away all
the shadows.

Signed-off-by: Tim Deegan <Tim.Deegan@xxxxxxxxxx>

dirty-vram-timing
Description: Text document

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[Xen-devel] [PATCH] Shadow dirty-VRAM: avoid multiple remove_all_mapping