static void balloon_stats_destroy_timer(VirtIOBalloon *s)
{
if (balloon_stats_enabled(s)) {
timer_del(s->stats_timer);
timer_free(s->stats_timer);
s->stats_timer = NULL;
s->stats_poll_interval = 0;
}
}
static int virtio_balloon_post_load_device(void *opaque, int version_id)
{
VirtIOBalloon *s = VIRTIO_BALLOON(opaque);
if (balloon_stats_enabled(s)) {
balloon_stats_change_timer(s, s->stats_poll_interval);
}
return 0;
}
static int virtio_balloon_load_device(VirtIODevice *vdev, QEMUFile *f,
int version_id)
{
VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
s->num_pages = qemu_get_be32(f);
s->actual = qemu_get_be32(f);
if (balloon_stats_enabled(s)) {
balloon_stats_change_timer(s, s->stats_poll_interval);
}
return 0;
}
static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
VirtQueueElement *elem;
VirtIOBalloonStat stat;
size_t offset = 0;
qemu_timeval tv;
elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
if (!elem) {
goto out;
}
if (s->stats_vq_elem != NULL) {
/* This should never happen if the driver follows the spec. */
virtqueue_push(vq, s->stats_vq_elem, 0);
virtio_notify(vdev, vq);
g_free(s->stats_vq_elem);
}
s->stats_vq_elem = elem;
/* 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 (iov_to_buf(elem->out_sg, elem->out_num, offset, &stat, sizeof(stat))
== sizeof(stat)) {
uint16_t tag = virtio_tswap16(vdev, stat.tag);
uint64_t val = virtio_tswap64(vdev, stat.val);
offset += sizeof(stat);
if (tag < VIRTIO_BALLOON_S_NR)
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__);
goto out;
}
s->stats_last_update = tv.tv_sec;
out:
if (balloon_stats_enabled(s)) {
balloon_stats_change_timer(s, s->stats_poll_interval);
}
}
static void balloon_stats_set_poll_interval(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
VirtIOBalloon *s = opaque;
Error *local_err = NULL;
int64_t value;
visit_type_int(v, name, &value, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (value < 0) {
error_setg(errp, "timer value must be greater than zero");
return;
}
if (value > UINT32_MAX) {
error_setg(errp, "timer value is too big");
return;
}
if (value == s->stats_poll_interval) {
return;
}
if (value == 0) {
/* timer=0 disables the timer */
balloon_stats_destroy_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 = timer_new_ms(QEMU_CLOCK_VIRTUAL, balloon_stats_poll_cb, s);
s->stats_poll_interval = value;
balloon_stats_change_timer(s, 0);
}
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;
visit_type_int(v, &value, name, errp);
if (error_is_set(errp)) {
return;
}
if (value < 0) {
error_setg(errp, "timer value must be greater than zero");
return;
}
if (value == s->stats_poll_interval) {
return;
}
if (value == 0) {
/* timer=0 disables the timer */
balloon_stats_destroy_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);
}
