From patchwork Thu Mar 3 10:44:26 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liang Li X-Patchwork-Id: 8491141 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 163A0C0553 for ; Thu, 3 Mar 2016 10:51:52 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C2E992010B for ; Thu, 3 Mar 2016 10:51:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5E36A201BB for ; Thu, 3 Mar 2016 10:51:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757409AbcCCKuq (ORCPT ); Thu, 3 Mar 2016 05:50:46 -0500 Received: from mga09.intel.com ([134.134.136.24]:46996 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757365AbcCCKun (ORCPT ); Thu, 3 Mar 2016 05:50:43 -0500 Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP; 03 Mar 2016 02:50:43 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,532,1449561600"; d="scan'208";a="757337853" Received: from ll.sh.intel.com (HELO localhost) ([10.239.13.27]) by orsmga003.jf.intel.com with ESMTP; 03 Mar 2016 02:50:40 -0800 From: Liang Li To: quintela@redhat.com, amit.shah@redhat.com, qemu-devel@nongnu.org, linux-kernel@vger.kernel.org Cc: mst@redhat.com, akpm@linux-foundation.org, pbonzini@redhat.com, rth@twiddle.net, ehabkost@redhat.com, linux-mm@kvack.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, dgilbert@redhat.com, Liang Li Subject: [RFC qemu 2/4] virtio-balloon: Add a new feature to balloon device Date: Thu, 3 Mar 2016 18:44:26 +0800 Message-Id: <1457001868-15949-3-git-send-email-liang.z.li@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1457001868-15949-1-git-send-email-liang.z.li@intel.com> References: <1457001868-15949-1-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-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Extend the virtio balloon device to support a new feature, this new feature can help to get guest's free pages information, which can be used for live migration optimzation. Signed-off-by: Liang Li --- balloon.c | 30 ++++++++- hw/virtio/virtio-balloon.c | 81 ++++++++++++++++++++++++- include/hw/virtio/virtio-balloon.h | 17 +++++- include/standard-headers/linux/virtio_balloon.h | 1 + include/sysemu/balloon.h | 10 ++- 5 files changed, 134 insertions(+), 5 deletions(-) diff --git a/balloon.c b/balloon.c index f2ef50c..a37717e 100644 --- a/balloon.c +++ b/balloon.c @@ -36,6 +36,7 @@ static QEMUBalloonEvent *balloon_event_fn; static QEMUBalloonStatus *balloon_stat_fn; +static QEMUBalloonFreePages *balloon_free_pages_fn; static void *balloon_opaque; static bool balloon_inhibited; @@ -65,9 +66,12 @@ static bool have_balloon(Error **errp) } int qemu_add_balloon_handler(QEMUBalloonEvent *event_func, - QEMUBalloonStatus *stat_func, void *opaque) + QEMUBalloonStatus *stat_func, + QEMUBalloonFreePages *free_pages_func, + void *opaque) { - if (balloon_event_fn || balloon_stat_fn || balloon_opaque) { + if (balloon_event_fn || balloon_stat_fn || balloon_free_pages_fn + || balloon_opaque) { /* We're already registered one balloon handler. How many can * a guest really have? */ @@ -75,6 +79,7 @@ int qemu_add_balloon_handler(QEMUBalloonEvent *event_func, } balloon_event_fn = event_func; balloon_stat_fn = stat_func; + balloon_free_pages_fn = free_pages_func; balloon_opaque = opaque; return 0; } @@ -86,6 +91,7 @@ void qemu_remove_balloon_handler(void *opaque) } balloon_event_fn = NULL; balloon_stat_fn = NULL; + balloon_free_pages_fn = NULL; balloon_opaque = NULL; } @@ -116,3 +122,23 @@ void qmp_balloon(int64_t target, Error **errp) trace_balloon_event(balloon_opaque, target); balloon_event_fn(balloon_opaque, target); } + +bool balloon_free_pages_support(void) +{ + return balloon_free_pages_fn ? true : false; +} + +int balloon_get_free_pages(unsigned long *free_pages_bitmap, + unsigned long *free_pages_count) +{ + if (!balloon_free_pages_fn) { + return -1; + } + + if (!free_pages_bitmap || !free_pages_count) { + return -1; + } + + return balloon_free_pages_fn(balloon_opaque, + free_pages_bitmap, free_pages_count); + } diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index e9c30e9..a5b9d08 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -76,6 +76,12 @@ static bool balloon_stats_supported(const VirtIOBalloon *s) return virtio_vdev_has_feature(vdev, VIRTIO_BALLOON_F_STATS_VQ); } +static bool balloon_free_pages_supported(const VirtIOBalloon *s) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(s); + return virtio_vdev_has_feature(vdev, VIRTIO_BALLOON_F_GET_FREE_PAGES); +} + static bool balloon_stats_enabled(const VirtIOBalloon *s) { return s->stats_poll_interval > 0; @@ -293,6 +299,37 @@ out: } } +static void virtio_balloon_get_free_pages(VirtIODevice *vdev, VirtQueue *vq) +{ + VirtIOBalloon *s = VIRTIO_BALLOON(vdev); + VirtQueueElement *elem; + size_t offset = 0; + uint64_t bitmap_bytes = 0, free_pages_count = 0; + + elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); + if (!elem) { + return; + } + s->free_pages_vq_elem = elem; + + if (!elem->out_num) { + return; + } + + iov_to_buf(elem->out_sg, elem->out_num, offset, + &free_pages_count, sizeof(uint64_t)); + + offset += sizeof(uint64_t); + iov_to_buf(elem->out_sg, elem->out_num, offset, + &bitmap_bytes, sizeof(uint64_t)); + + offset += sizeof(uint64_t); + iov_to_buf(elem->out_sg, elem->out_num, offset, + s->free_pages_bitmap, bitmap_bytes); + s->req_status = DONE; + s->free_pages_count = free_pages_count; +} + static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data) { VirtIOBalloon *dev = VIRTIO_BALLOON(vdev); @@ -362,6 +399,7 @@ static uint64_t virtio_balloon_get_features(VirtIODevice *vdev, uint64_t f, VirtIOBalloon *dev = VIRTIO_BALLOON(vdev); f |= dev->host_features; virtio_add_feature(&f, VIRTIO_BALLOON_F_STATS_VQ); + virtio_add_feature(&f, VIRTIO_BALLOON_F_GET_FREE_PAGES); return f; } @@ -372,6 +410,45 @@ static void virtio_balloon_stat(void *opaque, BalloonInfo *info) VIRTIO_BALLOON_PFN_SHIFT); } +static int virtio_balloon_free_pages(void *opaque, + unsigned long *free_pages_bitmap, + unsigned long *free_pages_count) +{ + VirtIOBalloon *s = opaque; + VirtIODevice *vdev = VIRTIO_DEVICE(s); + VirtQueueElement *elem = s->free_pages_vq_elem; + int len; + + if (!balloon_free_pages_supported(s)) { + return -1; + } + + if (s->req_status == NOT_STARTED) { + s->free_pages_bitmap = free_pages_bitmap; + s->req_status = STARTED; + s->mem_layout.low_mem = pc_get_lowmem(PC_MACHINE(current_machine)); + if (!elem->in_num) { + elem = virtqueue_pop(s->fvq, sizeof(VirtQueueElement)); + if (!elem) { + return 0; + } + s->free_pages_vq_elem = elem; + } + len = iov_from_buf(elem->in_sg, elem->in_num, 0, &s->mem_layout, + sizeof(s->mem_layout)); + virtqueue_push(s->fvq, elem, len); + virtio_notify(vdev, s->fvq); + return 0; + } else if (s->req_status == STARTED) { + return 0; + } else if (s->req_status == DONE) { + *free_pages_count = s->free_pages_count; + s->req_status = NOT_STARTED; + } + + return 1; +} + static void virtio_balloon_to_target(void *opaque, ram_addr_t target) { VirtIOBalloon *dev = VIRTIO_BALLOON(opaque); @@ -429,7 +506,8 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) sizeof(struct virtio_balloon_config)); ret = qemu_add_balloon_handler(virtio_balloon_to_target, - virtio_balloon_stat, s); + virtio_balloon_stat, + virtio_balloon_free_pages, s); if (ret < 0) { error_setg(errp, "Only one balloon device is supported"); @@ -440,6 +518,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) s->ivq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); s->dvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); s->svq = virtio_add_queue(vdev, 128, virtio_balloon_receive_stats); + s->fvq = virtio_add_queue(vdev, 128, virtio_balloon_get_free_pages); reset_stats(s); diff --git a/include/hw/virtio/virtio-balloon.h b/include/hw/virtio/virtio-balloon.h index 35f62ac..fc173e4 100644 --- a/include/hw/virtio/virtio-balloon.h +++ b/include/hw/virtio/virtio-balloon.h @@ -23,6 +23,16 @@ #define VIRTIO_BALLOON(obj) \ OBJECT_CHECK(VirtIOBalloon, (obj), TYPE_VIRTIO_BALLOON) +typedef enum virtio_req_status { + NOT_STARTED, + STARTED, + DONE, +} VIRTIO_REQ_STATUS; + +typedef struct MemLayout { + uint64_t low_mem; +} MemLayout; + typedef struct virtio_balloon_stat VirtIOBalloonStat; typedef struct virtio_balloon_stat_modern { @@ -33,16 +43,21 @@ typedef struct virtio_balloon_stat_modern { typedef struct VirtIOBalloon { VirtIODevice parent_obj; - VirtQueue *ivq, *dvq, *svq; + VirtQueue *ivq, *dvq, *svq, *fvq; uint32_t num_pages; uint32_t actual; uint64_t stats[VIRTIO_BALLOON_S_NR]; VirtQueueElement *stats_vq_elem; + VirtQueueElement *free_pages_vq_elem; size_t stats_vq_offset; QEMUTimer *stats_timer; int64_t stats_last_update; int64_t stats_poll_interval; uint32_t host_features; + uint64_t *free_pages_bitmap; + uint64_t free_pages_count; + MemLayout mem_layout; + VIRTIO_REQ_STATUS req_status; } VirtIOBalloon; #endif diff --git a/include/standard-headers/linux/virtio_balloon.h b/include/standard-headers/linux/virtio_balloon.h index 2e2a6dc..95b7d0c 100644 --- a/include/standard-headers/linux/virtio_balloon.h +++ b/include/standard-headers/linux/virtio_balloon.h @@ -34,6 +34,7 @@ #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ #define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue */ #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon on OOM */ +#define VIRTIO_BALLOON_F_GET_FREE_PAGES 3 /* Get the free pages bitmap */ /* Size of a PFN in the balloon interface. */ #define VIRTIO_BALLOON_PFN_SHIFT 12 diff --git a/include/sysemu/balloon.h b/include/sysemu/balloon.h index 3f976b4..205b272 100644 --- a/include/sysemu/balloon.h +++ b/include/sysemu/balloon.h @@ -18,11 +18,19 @@ typedef void (QEMUBalloonEvent)(void *opaque, ram_addr_t target); typedef void (QEMUBalloonStatus)(void *opaque, BalloonInfo *info); +typedef int (QEMUBalloonFreePages)(void *opaque, + unsigned long *free_pages_bitmap, + unsigned long *free_pages_count); int qemu_add_balloon_handler(QEMUBalloonEvent *event_func, - QEMUBalloonStatus *stat_func, void *opaque); + QEMUBalloonStatus *stat_func, + QEMUBalloonFreePages *free_pages_func, + void *opaque); void qemu_remove_balloon_handler(void *opaque); bool qemu_balloon_is_inhibited(void); void qemu_balloon_inhibit(bool state); +bool balloon_free_pages_support(void); +int balloon_get_free_pages(unsigned long *free_pages_bitmap, + unsigned long *free_pages_count); #endif