diff options
| author | Gal Hammer <ghammer@redhat.com> | 2018-01-14 12:06:56 +0200 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2018-01-18 21:52:38 +0200 |
| commit | 6f0bb230722931d17fb284eee8efd40b9d653822 (patch) | |
| tree | 197b4f2651ba4e0a42610cb50402391ea22d22fa /hw/virtio | |
| parent | 4fe6d78b2e241f41208dfb07605aace4becfc747 (diff) | |
| download | qemu-6f0bb230722931d17fb284eee8efd40b9d653822.tar.gz | |
virtio: improve virtio devices initialization time
The loading time of a VM is quite significant when its virtio
devices use a large amount of virt-queues (e.g. a virtio-serial
device with max_ports=511). Most of the time is spend in the
creation of all the required event notifiers (ioeventfd and memory
regions).
This patch pack all the changes to the memory regions in a
single memory transaction.
Reported-by: Sitong Liu <siliu@redhat.com>
Reported-by: Xiaoling Gao <xiagao@redhat.com>
Signed-off-by: Gal Hammer <ghammer@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw/virtio')
| -rw-r--r-- | hw/virtio/virtio.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index d6002ee550..3ac3491bee 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -2574,6 +2574,7 @@ static int virtio_device_start_ioeventfd_impl(VirtIODevice *vdev) VirtioBusState *qbus = VIRTIO_BUS(qdev_get_parent_bus(DEVICE(vdev))); int n, r, err; + memory_region_transaction_begin(); for (n = 0; n < VIRTIO_QUEUE_MAX; n++) { VirtQueue *vq = &vdev->vq[n]; if (!virtio_queue_get_num(vdev, n)) { @@ -2596,6 +2597,7 @@ static int virtio_device_start_ioeventfd_impl(VirtIODevice *vdev) } event_notifier_set(&vq->host_notifier); } + memory_region_transaction_commit(); return 0; assign_error: @@ -2609,6 +2611,7 @@ assign_error: r = virtio_bus_set_host_notifier(qbus, n, false); assert(r >= 0); } + memory_region_transaction_commit(); return err; } @@ -2625,6 +2628,7 @@ static void virtio_device_stop_ioeventfd_impl(VirtIODevice *vdev) VirtioBusState *qbus = VIRTIO_BUS(qdev_get_parent_bus(DEVICE(vdev))); int n, r; + memory_region_transaction_begin(); for (n = 0; n < VIRTIO_QUEUE_MAX; n++) { VirtQueue *vq = &vdev->vq[n]; @@ -2635,6 +2639,7 @@ static void virtio_device_stop_ioeventfd_impl(VirtIODevice *vdev) r = virtio_bus_set_host_notifier(qbus, n, false); assert(r >= 0); } + memory_region_transaction_commit(); } void virtio_device_stop_ioeventfd(VirtIODevice *vdev) |