From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx132.postini.com [74.125.245.132]) by kanga.kvack.org (Postfix) with SMTP id 534F46B0044 for ; Wed, 8 Aug 2012 21:39:44 -0400 (EDT) Message-ID: <502314C3.2020509@redhat.com> Date: Wed, 08 Aug 2012 21:39:15 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH v6 2/3] virtio_balloon: introduce migration primitives to balloon pages References: <5f4b30060e252e557882595984a8225ba6e0c9f2.1344463786.git.aquini@redhat.com> In-Reply-To: <5f4b30060e252e557882595984a8225ba6e0c9f2.1344463786.git.aquini@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Rafael Aquini Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, Rusty Russell , "Michael S. Tsirkin" , Mel Gorman , Andi Kleen , Andrew Morton , Konrad Rzeszutek Wilk , Minchan Kim On 08/08/2012 06:53 PM, Rafael Aquini wrote: > Memory fragmentation introduced by ballooning might reduce significantly > the number of 2MB contiguous memory blocks that can be used within a guest, > thus imposing performance penalties associated with the reduced number of > transparent huge pages that could be used by the guest workload. > > Besides making balloon pages movable at allocation time and introducing > the necessary primitives to perform balloon page migration/compaction, > this patch also introduces the following locking scheme to provide the > proper synchronization and protection for struct virtio_balloon elements > against concurrent accesses due to parallel operations introduced by > memory compaction / page migration. > - balloon_lock (mutex) : synchronizes the access demand to elements of > struct virtio_balloon and its queue operations; > - pages_lock (spinlock): special protection to balloon pages list against > concurrent list handling operations; > > Signed-off-by: Rafael Aquini Reviewed-by: Rik van Riel -- All rights reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org