From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: [PATCHv2 0/3] grant-table: optimize grant copies when
	crossing page boundaries
Date: Tue, 20 Jan 2015 18:19:46 +0000
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Cc: Keir Fraser <keir@xen.org>, Tim Deegan <tim@xen.org>, David Vrabel <david.vrabel@citrix.com>, Jan Beulich <jbeulich@suse.com>, Ian Campbell <ian.campbell@citrix.com>
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Netback tries (where possible) to minimize the number of copy ops in
the to-guest direction (since acquiring a page is expensive) this
reduces the number acquire operations at the expensive of more Rx
slots and more frags in the guests.

By deferring the release of the pages we can optimize the case where
the grant copier splits a copy into two operations to cross a page
boundary (either to split a source GFN into two granted pages, or a
two source into the same granted page).

Changes in v2:
- Split refactor into separate patch.
- Use in struct grant_copy_ptr in struct grant_copy_buf.
- Various style fixes.

David