From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rafael Aquini Subject: Re: [PATCH 0/4] enable migration of driver pages Date: Mon, 13 Jul 2015 10:20:14 -0400 Message-ID: <20150713142013.GA4025@t510.redhat.com> References: <1436776519-17337-1-git-send-email-gioh.kim@lge.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: jlayton-vpEMnDpepFuMZCB2o+C8xQ@public.gmane.org, bfields-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org, vbabka-AlSwsSmVLrQ@public.gmane.org, iamjoonsoo.kim-Hm3cg6mZ9cc@public.gmane.org, viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org, mst-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, koct9i-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, minchan-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, virtualization-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, Gioh Kim To: Gioh Kim Return-path: Content-Disposition: inline In-Reply-To: <1436776519-17337-1-git-send-email-gioh.kim-Hm3cg6mZ9cc@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org On Mon, Jul 13, 2015 at 05:35:15PM +0900, Gioh Kim wrote: > From: Gioh Kim > > Hello, > > This series try to enable migration of non-LRU pages, such as driver's page. > > My ARM-based platform occured severe fragmentation problem after long-term > (several days) test. Sometimes even order-3 page allocation failed. It has > memory size 512MB ~ 1024MB. 30% ~ 40% memory is consumed for graphic processing > and 20~30 memory is reserved for zram. > > I found that many pages of GPU driver and zram are non-movable pages. So I > reported Minchan Kim, the maintainer of zram, and he made the internal > compaction logic of zram. And I made the internal compaction of GPU driver. > > They reduced some fragmentation but they are not enough effective. > They are activated by its own interface, /sys, so they are not cooperative > with kernel compaction. If there is too much fragmentation and kernel starts > to compaction, zram and GPU driver cannot work with the kernel compaction. > > So I thought there needs a interface to combine driver and kernel compaction. > This patch adds a generic isolate/migrate/putback callbacks for page > address-space and a new interface to create anon-inode to manage > address_space_operation. The zram and GPU, and any other modules can create > anon_inode and register its own migration method. The kernel compaction can > call the registered migration when it does compaction. > > My GPU driver source is not in-kernel driver so that I apply the interface > into balloon driver. The balloon driver is already merged > into the kernel compaction as a corner-case. This patch have the balloon > driver migration be called by the generic interface. > > > This patch set combines 4 patches. > > 1. patch 1/4: get inode from anon_inodes > This patch adds new interface to create inode from anon_inodes. > > 2. patch 2/4: framework to isolate/migrate/putback page > Add isolatepage, putbackpage into address_space_operations > and wrapper function to call them. > > 3. patch 3/4: apply the framework into balloon driver > The balloon driver is applied into the framework. It gets a inode > from anon_inodes and register operations in the inode. > The kernel compaction calls generic interfaces, not balloon > driver interfaces. > Any other drivers can register operations via inode like this > to migrate it's pages. > > 4. patch 4/4: remove direct calling of migration of driver pages > Non-lru pages are also migrated with lru pages by move_to_new_page(). > > This patch set is tested: > - turn on Ubuntu 14.04 with 1G memory on qemu. > - do kernel building > - after several seconds check more than 512MB is used with free command > - command "balloon 512" in qemu monitor > - check hundreds MB of pages are migrated > > My thanks to Konstantin Khlebnikov for his reviews of the RFC patch set. > Most of the changes were based on his feedback. > > This patch-set is based on v4.1 > > > Gioh Kim (4): > fs/anon_inodes: new interface to create new inode > mm/compaction: enable mobile-page migration > mm/balloon: apply mobile page migratable into balloon > mm: remove direct calling of migration > > drivers/virtio/virtio_balloon.c | 3 ++ > fs/anon_inodes.c | 6 +++ > fs/proc/page.c | 3 ++ > include/linux/anon_inodes.h | 1 + > include/linux/balloon_compaction.h | 15 +++++-- > include/linux/compaction.h | 80 ++++++++++++++++++++++++++++++++++ > include/linux/fs.h | 2 + > include/linux/page-flags.h | 19 ++++++++ > include/uapi/linux/kernel-page-flags.h | 1 + > mm/balloon_compaction.c | 72 ++++++++++-------------------- > mm/compaction.c | 8 ++-- > mm/migrate.c | 24 +++------- > 12 files changed, 160 insertions(+), 74 deletions(-) > > -- > 2.1.4 > Acked-by: Rafael Aquini