From patchwork Fri Jul 15 02:47:26 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liang Li X-Patchwork-Id: 9231097 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 B0EB860574 for ; Fri, 15 Jul 2016 02:56:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A74AA28324 for ; Fri, 15 Jul 2016 02:56:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9C36A28329; Fri, 15 Jul 2016 02:56:01 +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=ham 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 2DF6028324 for ; Fri, 15 Jul 2016 02:56:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752349AbcGOCz7 (ORCPT ); Thu, 14 Jul 2016 22:55:59 -0400 Received: from mga11.intel.com ([192.55.52.93]:2710 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752146AbcGOCz6 (ORCPT ); Thu, 14 Jul 2016 22:55:58 -0400 Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga102.fm.intel.com with ESMTP; 14 Jul 2016 19:55:57 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,365,1464678000"; d="scan'208";a="1007200715" Received: from ll.sh.intel.com (HELO localhost) ([10.239.13.123]) by fmsmga001.fm.intel.com with ESMTP; 14 Jul 2016 19:55:55 -0700 From: Liang Li To: qemu-devel@nongnu.org Cc: mst@redhat.com, pbonzini@redhat.com, quintela@redhat.com, amit.shah@redhat.com, kvm@vger.kernel.org, dgilbert@redhat.com, thuth@redhat.com, Liang Li Subject: [QEMU v2 6/9] balloon: migrate vq elem to destination Date: Fri, 15 Jul 2016 10:47:26 +0800 Message-Id: <1468550849-22172-7-git-send-email-liang.z.li@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1468550849-22172-1-git-send-email-liang.z.li@intel.com> References: <1468550849-22172-1-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 After live migration, 'guest-stats' can't get the expected memory status in the guest. This issue is caused by commit 4eae2a657d. The value of 's->stats_vq_elem' will be NULL after live migration, and the check in the function 'balloon_stats_poll_cb()' will prevent the 'virtio_notify()' from executing. So guest will not update the memory status. Commit 4eae2a657d is doing the right thing, but 's->stats_vq_elem' should be treated as part of balloon device state and migrated to destination if it's not NULL to make everything works well. For the same reason, 's->misc_vq_elem' should be migrated to destination too. Michael has other idea to solve this issue, but he is busy at the moment, this patch can be used for test before his patch is ready. Signed-off-by: Liang Li --- hw/virtio/virtio-balloon.c | 36 ++++++++++++++++++++++++++++++++++-- 1 file changed, 34 insertions(+), 2 deletions(-) diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index b0c09a7..f9bf26d 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -31,6 +31,7 @@ #include "hw/virtio/virtio-access.h" #define BALLOON_PAGE_SIZE (1 << VIRTIO_BALLOON_PFN_SHIFT) +#define BALLOON_VERSION 2 static void balloon_page(void *addr, int deflate) { @@ -610,15 +611,33 @@ static void virtio_balloon_save(QEMUFile *f, void *opaque) static void virtio_balloon_save_device(VirtIODevice *vdev, QEMUFile *f) { VirtIOBalloon *s = VIRTIO_BALLOON(vdev); + uint16_t elem_num = 0; qemu_put_be32(f, s->num_pages); qemu_put_be32(f, s->actual); + if (s->stats_vq_elem != NULL) { + elem_num = 1; + } + qemu_put_be16(f, elem_num); + if (elem_num) { + qemu_put_virtqueue_element(f, s->stats_vq_elem); + } + + elem_num = 0; + if (s->misc_vq_elem != NULL) { + elem_num = 1; + } + qemu_put_be16(f, elem_num); + if (elem_num) { + qemu_put_virtqueue_element(f, s->misc_vq_elem); + } } static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id) { - if (version_id != 1) + if (version_id < 1 || version_id > BALLOON_VERSION) { return -EINVAL; + } return virtio_load(VIRTIO_DEVICE(opaque), f, version_id); } @@ -627,9 +646,22 @@ static int virtio_balloon_load_device(VirtIODevice *vdev, QEMUFile *f, int version_id) { VirtIOBalloon *s = VIRTIO_BALLOON(vdev); + uint16_t elem_num = 0; s->num_pages = qemu_get_be32(f); s->actual = qemu_get_be32(f); + if (version_id == BALLOON_VERSION) { + elem_num = qemu_get_be16(f); + if (elem_num == 1) { + s->stats_vq_elem = + qemu_get_virtqueue_element(f, sizeof(VirtQueueElement)); + } + elem_num = qemu_get_be16(f); + if (elem_num == 1) { + s->misc_vq_elem = + qemu_get_virtqueue_element(f, sizeof(VirtQueueElement)); + } + } if (balloon_stats_enabled(s)) { balloon_stats_change_timer(s, s->stats_poll_interval); @@ -665,7 +697,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) reset_stats(s); s->req_status = REQ_INIT; - register_savevm(dev, "virtio-balloon", -1, 1, + register_savevm(dev, "virtio-balloon", -1, BALLOON_VERSION, virtio_balloon_save, virtio_balloon_load, s); }