From patchwork Wed Jun 29 10:32:20 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liang Li X-Patchwork-Id: 9204803 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 86A8F60757 for ; Wed, 29 Jun 2016 10:41:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 74D2C2863B for ; Wed, 29 Jun 2016 10:41:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6842C28653; Wed, 29 Jun 2016 10:41:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B48D22863B for ; Wed, 29 Jun 2016 10:41:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752528AbcF2KlG (ORCPT ); Wed, 29 Jun 2016 06:41:06 -0400 Received: from mga03.intel.com ([134.134.136.65]:43063 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752316AbcF2KkK (ORCPT ); Wed, 29 Jun 2016 06:40:10 -0400 Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP; 29 Jun 2016 03:40:09 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,546,1459839600"; d="scan'208";a="726758822" Received: from ll.sh.intel.com (HELO localhost) ([10.239.13.123]) by FMSMGA003.fm.intel.com with ESMTP; 29 Jun 2016 03:40:07 -0700 From: Liang Li To: mst@redhat.com Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, dgilbert@redhat.com, quintela@redhat.com, Liang Li , Paolo Bonzini , Cornelia Huck , Amit Shah Subject: [PATCH v2 kernel 7/7] virtio-balloon: tell host vm's free page info Date: Wed, 29 Jun 2016 18:32:20 +0800 Message-Id: <1467196340-22079-8-git-send-email-liang.z.li@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1467196340-22079-1-git-send-email-liang.z.li@intel.com> References: <1467196340-22079-1-git-send-email-liang.z.li@intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Support the request for vm's free page information, response with a page bitmap. QEMU can make use of this free page bitmap to speed up live migration process by skipping process the free pages. Signed-off-by: Liang Li Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Cornelia Huck Cc: Amit Shah --- drivers/virtio/virtio_balloon.c | 104 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 98 insertions(+), 6 deletions(-) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 2d18ff6..5ca4ad3 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -62,10 +62,13 @@ module_param(oom_pages, int, S_IRUSR | S_IWUSR); MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); extern unsigned long get_max_pfn(void); +extern int get_free_pages(unsigned long start_pfn, unsigned long end_pfn, + unsigned long *bitmap, unsigned long len); + struct virtio_balloon { struct virtio_device *vdev; - struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; + struct virtqueue *inflate_vq, *deflate_vq, *stats_vq, *misc_vq; /* The balloon servicing is delegated to a freezable workqueue. */ struct work_struct update_balloon_stats_work; @@ -89,6 +92,8 @@ struct virtio_balloon { unsigned long pfn_limit; /* Used to record the processed pfn range */ unsigned long min_pfn, max_pfn, start_pfn, end_pfn; + /* Request header */ + struct balloon_req_hdr req_hdr; /* * The pages we've told the Host we're not using are enqueued * at vb_dev_info->pages list. @@ -373,6 +378,49 @@ static void update_balloon_stats(struct virtio_balloon *vb) pages_to_bytes(available)); } +static void update_free_pages_stats(struct virtio_balloon *vb, + unsigned long req_id) +{ + struct scatterlist sg_in, sg_out; + unsigned long pfn = 0, bmap_len, max_pfn; + struct virtqueue *vq = vb->misc_vq; + struct balloon_bmap_hdr *hdr = vb->bmap_hdr; + int ret = 1; + + max_pfn = get_max_pfn(); + mutex_lock(&vb->balloon_lock); + while (pfn < max_pfn) { + memset(vb->page_bitmap, 0, vb->bmap_len); + ret = get_free_pages(pfn, pfn + vb->pfn_limit, + vb->page_bitmap, vb->bmap_len * BITS_PER_BYTE); + hdr->cmd = cpu_to_virtio16(vb->vdev, BALLOON_GET_FREE_PAGES); + hdr->page_shift = cpu_to_virtio16(vb->vdev, PAGE_SHIFT); + hdr->req_id = cpu_to_virtio64(vb->vdev, req_id); + hdr->start_pfn = cpu_to_virtio64(vb->vdev, pfn); + bmap_len = vb->pfn_limit / BITS_PER_BYTE; + if (!ret) { + hdr->flag = cpu_to_virtio16(vb->vdev, + BALLOON_FLAG_DONE); + if (pfn + vb->pfn_limit > max_pfn) + bmap_len = (max_pfn - pfn) / BITS_PER_BYTE; + } else + hdr->flag = cpu_to_virtio16(vb->vdev, + BALLOON_FLAG_CONT); + hdr->bmap_len = cpu_to_virtio64(vb->vdev, bmap_len); + sg_init_one(&sg_out, hdr, + sizeof(struct balloon_bmap_hdr) + bmap_len); + + virtqueue_add_outbuf(vq, &sg_out, 1, vb, GFP_KERNEL); + virtqueue_kick(vq); + pfn += vb->pfn_limit; + } + + sg_init_one(&sg_in, &vb->req_hdr, sizeof(vb->req_hdr)); + virtqueue_add_inbuf(vq, &sg_in, 1, &vb->req_hdr, GFP_KERNEL); + virtqueue_kick(vq); + mutex_unlock(&vb->balloon_lock); +} + /* * While most virtqueues communicate guest-initiated requests to the hypervisor, * the stats queue operates in reverse. The driver initializes the virtqueue @@ -511,18 +559,49 @@ static void update_balloon_size_func(struct work_struct *work) queue_work(system_freezable_wq, work); } +static void misc_handle_rq(struct virtio_balloon *vb) +{ + struct balloon_req_hdr *ptr_hdr; + unsigned int len; + + ptr_hdr = virtqueue_get_buf(vb->misc_vq, &len); + if (!ptr_hdr || len != sizeof(vb->req_hdr)) + return; + + switch (ptr_hdr->cmd) { + case BALLOON_GET_FREE_PAGES: + update_free_pages_stats(vb, ptr_hdr->param); + break; + default: + break; + } +} + +static void misc_request(struct virtqueue *vq) +{ + struct virtio_balloon *vb = vq->vdev->priv; + + misc_handle_rq(vb); +} + static int init_vqs(struct virtio_balloon *vb) { - struct virtqueue *vqs[3]; - vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request }; - static const char * const names[] = { "inflate", "deflate", "stats" }; + struct virtqueue *vqs[4]; + vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, + stats_request, misc_request }; + static const char * const names[] = { "inflate", "deflate", "stats", + "misc" }; int err, nvqs; /* * We expect two virtqueues: inflate and deflate, and * optionally stat. */ - nvqs = virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_STATS_VQ) ? 3 : 2; + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_MISC_VQ)) + nvqs = 4; + else + nvqs = virtio_has_feature(vb->vdev, + VIRTIO_BALLOON_F_STATS_VQ) ? 3 : 2; err = vb->vdev->config->find_vqs(vb->vdev, nvqs, vqs, callbacks, names); if (err) return err; @@ -543,6 +622,16 @@ static int init_vqs(struct virtio_balloon *vb) BUG(); virtqueue_kick(vb->stats_vq); } + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_MISC_VQ)) { + struct scatterlist sg_in; + + vb->misc_vq = vqs[3]; + sg_init_one(&sg_in, &vb->req_hdr, sizeof(vb->req_hdr)); + if (virtqueue_add_inbuf(vb->misc_vq, &sg_in, 1, + &vb->req_hdr, GFP_KERNEL) < 0) + BUG(); + virtqueue_kick(vb->misc_vq); + } return 0; } @@ -639,8 +728,10 @@ static int virtballoon_probe(struct virtio_device *vdev) vb->bmap_hdr = kzalloc(hdr_len + vb->bmap_len, GFP_KERNEL); /* Clear the feature bit if memory allocation fails */ - if (!vb->bmap_hdr) + if (!vb->bmap_hdr) { __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_PAGE_BITMAP); + __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_MISC_VQ); + } else vb->page_bitmap = vb->bmap_hdr + hdr_len; mutex_init(&vb->balloon_lock); @@ -743,6 +834,7 @@ static unsigned int features[] = { VIRTIO_BALLOON_F_STATS_VQ, VIRTIO_BALLOON_F_DEFLATE_ON_OOM, VIRTIO_BALLOON_F_PAGE_BITMAP, + VIRTIO_BALLOON_F_MISC_VQ, }; static struct virtio_driver virtio_balloon_driver = {