From patchwork Tue Dec 4 15:04:47 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luiz Capitulino X-Patchwork-Id: 203679 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 7214D2C0086 for ; Wed, 5 Dec 2012 02:16:59 +1100 (EST) Received: from localhost ([::1]:41792 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TfuEz-0004IA-FW for incoming@patchwork.ozlabs.org; Tue, 04 Dec 2012 10:16:57 -0500 Received: from eggs.gnu.org ([208.118.235.92]:53108) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TfuEj-0004Gt-Lx for qemu-devel@nongnu.org; Tue, 04 Dec 2012 10:16:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TfuEc-0003vv-S6 for qemu-devel@nongnu.org; Tue, 04 Dec 2012 10:16:41 -0500 Received: from mx1.redhat.com ([209.132.183.28]:9822) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TfuEc-0003vh-Kr for qemu-devel@nongnu.org; Tue, 04 Dec 2012 10:16:34 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id qB4F4uVJ009615 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 4 Dec 2012 10:04:56 -0500 Received: from localhost (ovpn-113-104.phx2.redhat.com [10.3.113.104]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id qB4F4t0t013046; Tue, 4 Dec 2012 10:04:55 -0500 From: Luiz Capitulino To: qemu-devel@nongnu.org Date: Tue, 4 Dec 2012 13:04:47 -0200 Message-Id: <1354633488-24112-3-git-send-email-lcapitulino@redhat.com> In-Reply-To: <1354633488-24112-1-git-send-email-lcapitulino@redhat.com> References: <1354633488-24112-1-git-send-email-lcapitulino@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: aliguori@us.ibm.com, mdroth@linux.vnet.ibm.com, agl@us.ibm.com Subject: [Qemu-devel] [RFC 2/3] virtio-balloon: re-enable balloon stats X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org The statistics are now available through device properties via a polling mechanism. First, a client has to enable polling, then it can query the stats. The following control properties are introduced: o stats-polling-interval: a value greater than zero enables polling in the specified interval (in seconds). When value equals zero, polling is disabled. If polling is already enabled and a value greater than zero is written, the polling interval time is changed o stats-last-update: last stats update timestamp, in seconds. The following stats properties are introduced: o stat-swap-in o stat-swap-out o stat-major-faults o stat-minor-faults o stat-free-memory o stat-total-memory All values are in bytes. A value of -1 means that the statistic isn't available right now. FIXME: Can balloon_stats_poll_cb(), balloon_stats_set_poll_interval(), virtio_balloon_handle_output() can run in parallel? XXX: Should we return an error instead of -1? Might require a specific error. Although this is not exactly a failure... Signed-off-by: Luiz Capitulino --- NOTE: Anthony suggested having a bool to enable/disable polling, but I prefer to let the client specify the polling interval. I can revisit this, though. hw/virtio-balloon.c | 156 +++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 155 insertions(+), 1 deletion(-) diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c index 4398025..06af18f 100644 --- a/hw/virtio-balloon.c +++ b/hw/virtio-balloon.c @@ -22,6 +22,8 @@ #include "virtio-balloon.h" #include "kvm.h" #include "exec-memory.h" +#include "qemu-timer.h" +#include "qapi/qapi-visit-core.h" #if defined(__linux__) #include @@ -36,6 +38,9 @@ typedef struct VirtIOBalloon uint64_t stats[VIRTIO_BALLOON_S_NR]; VirtQueueElement stats_vq_elem; size_t stats_vq_offset; + QEMUTimer *stats_timer; + int64_t stats_last_update; + int64_t stats_poll_interval; DeviceState *qdev; } VirtIOBalloon; @@ -53,6 +58,16 @@ static void balloon_page(void *addr, int deflate) #endif } +static const char *balloon_stat_names[] = { + [VIRTIO_BALLOON_S_SWAP_IN] = "stat-swap-in", + [VIRTIO_BALLOON_S_SWAP_OUT] = "stat-swap-out", + [VIRTIO_BALLOON_S_MAJFLT] = "stat-major-faults", + [VIRTIO_BALLOON_S_MINFLT] = "stat-minor-faults", + [VIRTIO_BALLOON_S_MEMFREE] = "stat-free-memory", + [VIRTIO_BALLOON_S_MEMTOT] = "stat-total-memory", + [VIRTIO_BALLOON_S_NR] = NULL +}; + /* * reset_stats - Mark all items in the stats array as unset * @@ -67,6 +82,119 @@ static inline void reset_stats(VirtIOBalloon *dev) for (i = 0; i < VIRTIO_BALLOON_S_NR; dev->stats[i++] = -1); } +static bool balloon_stats_supported(const VirtIOBalloon *s) +{ + return s->vdev.guest_features & (1 << VIRTIO_BALLOON_F_STATS_VQ); +} + +static bool balloon_stats_enabled(const VirtIOBalloon *s) +{ + return s->stats_poll_interval > 0; +} + +static void balloon_stats_disable_timer(VirtIOBalloon *s) +{ + if (balloon_stats_enabled(s)) { + qemu_del_timer(s->stats_timer); + qemu_free_timer(s->stats_timer); + s->stats_timer = NULL; + s->stats_poll_interval = 0; + } +} + +static void balloon_stats_change_timer(VirtIOBalloon *s, int secs) +{ + qemu_mod_timer(s->stats_timer, qemu_get_clock_ms(vm_clock) + secs * 1000); +} + +static void balloon_stats_poll_cb(void *opaque) +{ + VirtIOBalloon *s = opaque; + + virtqueue_push(s->svq, &s->stats_vq_elem, s->stats_vq_offset); + virtio_notify(&s->vdev, s->svq); + + balloon_stats_change_timer(s, s->stats_poll_interval); +} + +static void balloon_stats_get_last_update(Object *obj, struct Visitor *v, + void *opaque, const char *name, + Error **errp) +{ + VirtIOBalloon *s = opaque; + visit_type_int(v, &s->stats_last_update, name, errp); +} + +static void balloon_stats_get_stat(Object *obj, struct Visitor *v, + void *opaque, const char *name, Error **errp) +{ + VirtIOBalloon *s = opaque; + int i; + + for (i = 0; i < VIRTIO_BALLOON_S_NR; i++) { + if (!strcmp(balloon_stat_names[i], name)) { + visit_type_int(v, (int64_t *) &s->stats[i], name, errp); + return; + } + } + + error_setg(errp, "invalid property name '%s'", name); +} + +static void balloon_stats_get_poll_interval(Object *obj, struct Visitor *v, + void *opaque, const char *name, + Error **errp) +{ + VirtIOBalloon *s = opaque; + visit_type_int(v, &s->stats_poll_interval, name, errp); +} + +static void balloon_stats_set_poll_interval(Object *obj, struct Visitor *v, + void *opaque, const char *name, + Error **errp) +{ + VirtIOBalloon *s = opaque; + int64_t value; + + if (!balloon_stats_supported(s)) { + error_setg(errp, "guest doesn\'t support balloon stats"); + return; + } + + visit_type_int(v, &value, name, errp); + if (error_is_set(errp)) { + return; + } + + if (value < 0) { + error_setg(errp, "timer value must be positive"); + return; + } + + if (value == s->stats_poll_interval) { + return; + } + + if (value == 0) { + /* timer=0 disables the timer */ + balloon_stats_disable_timer(s); + return; + } + + if (balloon_stats_enabled(s)) { + /* timer interval change */ + s->stats_poll_interval = value; + balloon_stats_change_timer(s, value); + return; + } + + /* create a new timer */ + g_assert(s->stats_timer == NULL); + s->stats_timer = qemu_new_timer_ms(vm_clock, balloon_stats_poll_cb, s); + s->stats_poll_interval = value; + balloon_stats_change_timer(s, 0); +} + static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) { VirtIOBalloon *s = to_virtio_balloon(vdev); @@ -107,11 +235,16 @@ static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq) VirtQueueElement *elem = &s->stats_vq_elem; VirtIOBalloonStat stat; size_t offset = 0; + qemu_timeval tv; if (!virtqueue_pop(vq, elem)) { return; } + if (!balloon_stats_enabled(s)) { + return; + } + /* Initialize the stats to get rid of any stale values. This is only * needed to handle the case where a guest supports fewer stats than it * used to (ie. it has booted into an old kernel). @@ -128,6 +261,13 @@ static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq) s->stats[tag] = val; } s->stats_vq_offset = offset; + + if (qemu_gettimeofday(&tv) < 0) { + fprintf(stderr, "warning: %s: failed to get time of day\n", __func__); + return; + } + + s->stats_last_update = tv.tv_sec; } static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data) @@ -212,7 +352,7 @@ static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id) VirtIODevice *virtio_balloon_init(DeviceState *dev) { VirtIOBalloon *s; - int ret; + int i, ret; s = (VirtIOBalloon *)virtio_common_init("virtio-balloon", VIRTIO_ID_BALLOON, @@ -239,6 +379,19 @@ VirtIODevice *virtio_balloon_init(DeviceState *dev) register_savevm(dev, "virtio-balloon", -1, 1, virtio_balloon_save, virtio_balloon_load, s); + for (i = 0; i < VIRTIO_BALLOON_S_NR; i++) { + object_property_add(OBJECT(dev), balloon_stat_names[i], "int", + balloon_stats_get_stat, NULL, NULL, s, NULL); + } + + object_property_add(OBJECT(dev), "stats-last-update", "int", + balloon_stats_get_last_update, NULL, NULL, s, NULL); + + object_property_add(OBJECT(dev), "stats-polling-interval", "int", + balloon_stats_get_poll_interval, + balloon_stats_set_poll_interval, + NULL, s, NULL); + return &s->vdev; } @@ -246,6 +399,7 @@ void virtio_balloon_exit(VirtIODevice *vdev) { VirtIOBalloon *s = DO_UPCAST(VirtIOBalloon, vdev, vdev); + balloon_stats_disable_timer(s); qemu_remove_balloon_handler(s); unregister_savevm(s->qdev, "virtio-balloon", s); virtio_cleanup(vdev);