From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tim Deegan Subject: Re: [PATCH 4 of 4] xen, pod: Try to reclaim superpages when ballooning down Date: Thu, 28 Jun 2012 13:45:08 +0100 Message-ID: <20120628124508.GK34995@ocelot.phlegethon.org> References: <71a22d6d940f27d8dfbc.1340816251@elijah> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <71a22d6d940f27d8dfbc.1340816251@elijah> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: George Dunlap Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org At 17:57 +0100 on 27 Jun (1340819851), George Dunlap wrote: > xen,pod: Try to reclaim superpages when ballooning down > > Windows balloon drivers can typically only get 4k pages from the kernel, > and so hand them back at that level. Try to regain superpages by checking > the superpage frame that the 4k page is in to see if we can reclaim the whole > thing for the PoD cache. > > This also modifies p2m_pod_zero_check_superpage() to return SUPERPAGE_PAGES on > success. > > v2: > - Rewritten to simply to the check as in demand-fault case, without needing > to know that the p2m entry is a superpage. > - Also, took out the re-writing of the reclaim loop, leaving it optimized for > 4k pages (by far the most common case), and simplifying the patch. > Acked-by: Tim Deegan