diff options
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/virtio-balloon.c | 127 | ||||
| -rw-r--r-- | hw/virtio-balloon.h | 15 |
2 files changed, 138 insertions, 4 deletions
diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c index e17880ff7c..086d9d1ecd 100644 --- a/hw/virtio-balloon.c +++ b/hw/virtio-balloon.c @@ -16,9 +16,13 @@ #include "pc.h" #include "sysemu.h" #include "cpu.h" +#include "monitor.h" #include "balloon.h" #include "virtio-balloon.h" #include "kvm.h" +#include "qlist.h" +#include "qint.h" +#include "qstring.h" #if defined(__linux__) #include <sys/mman.h> @@ -27,9 +31,14 @@ typedef struct VirtIOBalloon { VirtIODevice vdev; - VirtQueue *ivq, *dvq; + VirtQueue *ivq, *dvq, *svq; uint32_t num_pages; uint32_t actual; + uint64_t stats[VIRTIO_BALLOON_S_NR]; + VirtQueueElement stats_vq_elem; + size_t stats_vq_offset; + MonitorCompletion *stats_callback; + void *stats_opaque_callback_data; } VirtIOBalloon; static VirtIOBalloon *to_virtio_balloon(VirtIODevice *vdev) @@ -46,6 +55,42 @@ static void balloon_page(void *addr, int deflate) #endif } +/* + * reset_stats - Mark all items in the stats array as unset + * + * This function needs to be called at device intialization and before + * before updating to a set of newly-generated stats. This will ensure that no + * stale values stick around in case the guest reports a subset of the supported + * statistics. + */ +static inline void reset_stats(VirtIOBalloon *dev) +{ + int i; + for (i = 0; i < VIRTIO_BALLOON_S_NR; dev->stats[i++] = -1); +} + +static void stat_put(QDict *dict, const char *label, uint64_t val) +{ + if (val != -1) + qdict_put(dict, label, qint_from_int(val)); +} + +static QObject *get_stats_qobject(VirtIOBalloon *dev) +{ + QDict *dict = qdict_new(); + uint32_t actual = ram_size - (dev->actual << VIRTIO_BALLOON_PFN_SHIFT); + + stat_put(dict, "actual", actual); + stat_put(dict, "mem_swapped_in", dev->stats[VIRTIO_BALLOON_S_SWAP_IN]); + stat_put(dict, "mem_swapped_out", dev->stats[VIRTIO_BALLOON_S_SWAP_OUT]); + stat_put(dict, "major_page_faults", dev->stats[VIRTIO_BALLOON_S_MAJFLT]); + stat_put(dict, "minor_page_faults", dev->stats[VIRTIO_BALLOON_S_MINFLT]); + stat_put(dict, "free_mem", dev->stats[VIRTIO_BALLOON_S_MEMFREE]); + stat_put(dict, "total_mem", dev->stats[VIRTIO_BALLOON_S_MEMTOT]); + + return QOBJECT(dict); +} + /* FIXME: once we do a virtio refactoring, this will get subsumed into common * code */ static size_t memcpy_from_iovector(void *data, size_t offset, size_t size, @@ -104,6 +149,51 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) } } +static void complete_stats_request(VirtIOBalloon *vb) +{ + QObject *stats; + + if (!vb->stats_opaque_callback_data) + return; + + stats = get_stats_qobject(vb); + vb->stats_callback(vb->stats_opaque_callback_data, stats); + qobject_decref(stats); + vb->stats_opaque_callback_data = NULL; + vb->stats_callback = NULL; +} + +static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq) +{ + VirtIOBalloon *s = DO_UPCAST(VirtIOBalloon, vdev, vdev); + VirtQueueElement *elem = &s->stats_vq_elem; + VirtIOBalloonStat stat; + size_t offset = 0; + + if (!virtqueue_pop(vq, elem)) { + 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). + */ + reset_stats(s); + + while (memcpy_from_iovector(&stat, offset, sizeof(stat), elem->out_sg, + elem->out_num) == sizeof(stat)) { + uint16_t tag = tswap16(stat.tag); + uint64_t val = tswap64(stat.val); + + offset += sizeof(stat); + if (tag < VIRTIO_BALLOON_S_NR) + s->stats[tag] = val; + } + s->stats_vq_offset = offset; + + complete_stats_request(s); +} + static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data) { VirtIOBalloon *dev = to_virtio_balloon(vdev); @@ -126,10 +216,12 @@ static void virtio_balloon_set_config(VirtIODevice *vdev, static uint32_t virtio_balloon_get_features(VirtIODevice *vdev, uint32_t f) { + f |= (1 << VIRTIO_BALLOON_F_STATS_VQ); return f; } -static ram_addr_t virtio_balloon_to_target(void *opaque, ram_addr_t target) +static void virtio_balloon_to_target(void *opaque, ram_addr_t target, + MonitorCompletion cb, void *cb_data) { VirtIOBalloon *dev = opaque; @@ -139,9 +231,26 @@ static ram_addr_t virtio_balloon_to_target(void *opaque, ram_addr_t target) if (target) { dev->num_pages = (ram_size - target) >> VIRTIO_BALLOON_PFN_SHIFT; virtio_notify_config(&dev->vdev); + } else { + /* For now, only allow one request at a time. This restriction can be + * removed later by queueing callback and data pairs. + */ + if (dev->stats_callback != NULL) { + return; + } + dev->stats_callback = cb; + dev->stats_opaque_callback_data = cb_data; + if (dev->vdev.guest_features & (1 << VIRTIO_BALLOON_F_STATS_VQ)) { + virtqueue_push(dev->svq, &dev->stats_vq_elem, dev->stats_vq_offset); + virtio_notify(&dev->vdev, dev->svq); + } else { + /* Stats are not supported. Clear out any stale values that might + * have been set by a more featureful guest kernel. + */ + reset_stats(dev); + complete_stats_request(dev); + } } - - return ram_size - (dev->actual << VIRTIO_BALLOON_PFN_SHIFT); } static void virtio_balloon_save(QEMUFile *f, void *opaque) @@ -152,6 +261,10 @@ static void virtio_balloon_save(QEMUFile *f, void *opaque) qemu_put_be32(f, s->num_pages); qemu_put_be32(f, s->actual); + qemu_put_buffer(f, (uint8_t *)&s->stats_vq_elem, sizeof(VirtQueueElement)); + qemu_put_buffer(f, (uint8_t *)&s->stats_vq_offset, sizeof(size_t)); + qemu_put_buffer(f, (uint8_t *)&s->stats_callback, sizeof(MonitorCompletion)); + qemu_put_buffer(f, (uint8_t *)&s->stats_opaque_callback_data, sizeof(void)); } static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id) @@ -165,6 +278,10 @@ static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id) s->num_pages = qemu_get_be32(f); s->actual = qemu_get_be32(f); + qemu_get_buffer(f, (uint8_t *)&s->stats_vq_elem, sizeof(VirtQueueElement)); + qemu_get_buffer(f, (uint8_t *)&s->stats_vq_offset, sizeof(size_t)); + qemu_get_buffer(f, (uint8_t *)&s->stats_callback, sizeof(MonitorCompletion)); + qemu_get_buffer(f, (uint8_t *)&s->stats_opaque_callback_data, sizeof(void)); return 0; } @@ -183,7 +300,9 @@ VirtIODevice *virtio_balloon_init(DeviceState *dev) s->ivq = virtio_add_queue(&s->vdev, 128, virtio_balloon_handle_output); s->dvq = virtio_add_queue(&s->vdev, 128, virtio_balloon_handle_output); + s->svq = virtio_add_queue(&s->vdev, 128, virtio_balloon_receive_stats); + reset_stats(s); qemu_add_balloon_handler(virtio_balloon_to_target, s); register_savevm("virtio-balloon", -1, 1, virtio_balloon_save, virtio_balloon_load, s); diff --git a/hw/virtio-balloon.h b/hw/virtio-balloon.h index 9a0d119e42..e20cf6bc0d 100644 --- a/hw/virtio-balloon.h +++ b/hw/virtio-balloon.h @@ -25,6 +25,7 @@ /* The feature bitmap for virtio balloon */ #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ +#define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory stats virtqueue */ /* Size of a PFN in the balloon interface. */ #define VIRTIO_BALLOON_PFN_SHIFT 12 @@ -37,4 +38,18 @@ struct virtio_balloon_config uint32_t actual; }; +/* Memory Statistics */ +#define VIRTIO_BALLOON_S_SWAP_IN 0 /* Amount of memory swapped in */ +#define VIRTIO_BALLOON_S_SWAP_OUT 1 /* Amount of memory swapped out */ +#define VIRTIO_BALLOON_S_MAJFLT 2 /* Number of major faults */ +#define VIRTIO_BALLOON_S_MINFLT 3 /* Number of minor faults */ +#define VIRTIO_BALLOON_S_MEMFREE 4 /* Total amount of free memory */ +#define VIRTIO_BALLOON_S_MEMTOT 5 /* Total amount of memory */ +#define VIRTIO_BALLOON_S_NR 6 + +typedef struct VirtIOBalloonStat { + uint16_t tag; + uint64_t val; +} __attribute__((packed)) VirtIOBalloonStat; + #endif |