diff options
Diffstat (limited to 'hw/virtio/virtio-balloon.c')
| -rw-r--r-- | hw/virtio/virtio-balloon.c | 36 |
1 files changed, 28 insertions, 8 deletions
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index 10507b2a43..ae31f0817a 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -63,6 +63,12 @@ static bool virtio_balloon_pbp_matches(PartiallyBalloonedPage *pbp, return pbp->base_gpa == base_gpa; } +static bool virtio_balloon_inhibited(void) +{ + /* Postcopy cannot deal with concurrent discards, so it's special. */ + return ram_block_discard_is_disabled() || migration_in_incoming_postcopy(); +} + static void balloon_inflate_page(VirtIOBalloon *balloon, MemoryRegion *mr, hwaddr mr_offset, PartiallyBalloonedPage *pbp) @@ -336,7 +342,7 @@ static void virtio_balloon_handle_report(VirtIODevice *vdev, VirtQueue *vq) * accessible by another device or process, or if the guest is * expecting it to retain a non-zero value. */ - if (qemu_balloon_is_inhibited() || dev->poison_val) { + if (virtio_balloon_inhibited() || dev->poison_val) { goto skip_element; } @@ -421,7 +427,7 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) trace_virtio_balloon_handle_output(memory_region_name(section.mr), pa); - if (!qemu_balloon_is_inhibited()) { + if (!virtio_balloon_inhibited()) { if (vq == s->ivq) { balloon_inflate_page(s, section.mr, section.offset_within_region, &pbp); @@ -628,8 +634,13 @@ static void virtio_balloon_free_page_done(VirtIOBalloon *s) { VirtIODevice *vdev = VIRTIO_DEVICE(s); - s->free_page_report_status = FREE_PAGE_REPORT_S_DONE; - virtio_notify_config(vdev); + if (s->free_page_report_status != FREE_PAGE_REPORT_S_DONE) { + /* See virtio_balloon_free_page_stop() */ + qemu_mutex_lock(&s->free_page_lock); + s->free_page_report_status = FREE_PAGE_REPORT_S_DONE; + qemu_mutex_unlock(&s->free_page_lock); + virtio_notify_config(vdev); + } } static int @@ -653,17 +664,26 @@ virtio_balloon_free_page_report_notify(NotifierWithReturn *n, void *data) case PRECOPY_NOTIFY_SETUP: precopy_enable_free_page_optimization(); break; - case PRECOPY_NOTIFY_COMPLETE: - case PRECOPY_NOTIFY_CLEANUP: case PRECOPY_NOTIFY_BEFORE_BITMAP_SYNC: virtio_balloon_free_page_stop(dev); break; case PRECOPY_NOTIFY_AFTER_BITMAP_SYNC: if (vdev->vm_running) { virtio_balloon_free_page_start(dev); - } else { - virtio_balloon_free_page_done(dev); + break; } + /* + * Set S_DONE before migrating the vmstate, so the guest will reuse + * all hinted pages once running on the destination. Fall through. + */ + case PRECOPY_NOTIFY_CLEANUP: + /* + * Especially, if something goes wrong during precopy or if migration + * is canceled, we have to properly communicate S_DONE to the VM. + */ + virtio_balloon_free_page_done(dev); + break; + case PRECOPY_NOTIFY_COMPLETE: break; default: virtio_error(vdev, "%s: %d reason unknown", __func__, pnd->reason); |