On 05/29/2018 11:24 PM, Michael S. Tsirkin wrote:
On Tue, Apr 24, 2018 at 02:13:47PM +0800, Wei Wang wrote:
+/*
+ * Balloon will report pages which were free at the time of this call. As the
+ * reporting happens asynchronously, dirty bit logging must be enabled before
+ * this call is made.
+ */
+void balloon_free_page_start(void)
+{
+ balloon_free_page_start_fn(balloon_opaque);
+}
Please create notifier support, not a single global.
OK. The start is called at the end of bitmap_sync, and the stop is
called at the beginning of bitmap_sync. In this case, we will need to
add two migration states, MIGRATION_STATUS_BEFORE_BITMAP_SYNC and
MIGRATION_STATUS_AFTER_BITMAP_SYNC, right?
+static void virtio_balloon_poll_free_page_hints(void *opaque)
+{
+ VirtQueueElement *elem;
+ VirtIOBalloon *dev = opaque;
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VirtQueue *vq = dev->free_page_vq;
+ uint32_t id;
+ size_t size;
+
+ while (1) {
+ qemu_mutex_lock(&dev->free_page_lock);
+ while (dev->block_iothread) {
+ qemu_cond_wait(&dev->free_page_cond, &dev->free_page_lock);
+ }
+
+ /*
+ * If the migration thread actively stops the reporting, exit
+ * immediately.
+ */
+ if (dev->free_page_report_status == FREE_PAGE_REPORT_S_STOP) {
Please refactor this : move loop body into a function so
you can do lock/unlock in a single place.
Sounds good.
+
+static bool virtio_balloon_free_page_support(void *opaque)
+{
+ VirtIOBalloon *s = opaque;
+ VirtIODevice *vdev = VIRTIO_DEVICE(s);
+
+ return virtio_vdev_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT);
or if poison is negotiated.
Will make it
return virtio_vdev_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT) &&
!virtio_vdev_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)
Best,
Wei
