diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2017-01-27 16:40:17 +0100 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2017-02-17 21:52:30 +0200 |
commit | c611c76417f52b335ecaab01c61743e3b705eb7c (patch) | |
tree | a8cec626b13d7fccd8f43857745c1a27d6f3db70 /hw/virtio | |
parent | 5eba0404b98294906134c06519c272bfb5f50453 (diff) |
virtio: add MemoryListener to cache ring translations
The cached translations are RCU-protected to allow efficient use
when processing virtqueues.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@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 | 105 |
1 files changed, 102 insertions, 3 deletions
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 71e41f66b1..b75cb52fcc 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -60,6 +60,13 @@ typedef struct VRingUsed VRingUsedElem ring[0]; } VRingUsed; +typedef struct VRingMemoryRegionCaches { + struct rcu_head rcu; + MemoryRegionCache desc; + MemoryRegionCache avail; + MemoryRegionCache used; +} VRingMemoryRegionCaches; + typedef struct VRing { unsigned int num; @@ -68,6 +75,7 @@ typedef struct VRing hwaddr desc; hwaddr avail; hwaddr used; + VRingMemoryRegionCaches *caches; } VRing; struct VirtQueue @@ -104,6 +112,51 @@ struct VirtQueue QLIST_ENTRY(VirtQueue) node; }; +static void virtio_free_region_cache(VRingMemoryRegionCaches *caches) +{ + if (!caches) { + return; + } + + address_space_cache_destroy(&caches->desc); + address_space_cache_destroy(&caches->avail); + address_space_cache_destroy(&caches->used); + g_free(caches); +} + +static void virtio_init_region_cache(VirtIODevice *vdev, int n) +{ + VirtQueue *vq = &vdev->vq[n]; + VRingMemoryRegionCaches *old = vq->vring.caches; + VRingMemoryRegionCaches *new; + hwaddr addr, size; + int event_size; + + event_size = virtio_vdev_has_feature(vq->vdev, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + + addr = vq->vring.desc; + if (!addr) { + return; + } + new = g_new0(VRingMemoryRegionCaches, 1); + size = virtio_queue_get_desc_size(vdev, n); + address_space_cache_init(&new->desc, vdev->dma_as, + addr, size, false); + + size = virtio_queue_get_used_size(vdev, n) + event_size; + address_space_cache_init(&new->used, vdev->dma_as, + vq->vring.used, size, true); + + size = virtio_queue_get_avail_size(vdev, n) + event_size; + address_space_cache_init(&new->avail, vdev->dma_as, + vq->vring.avail, size, false); + + atomic_rcu_set(&vq->vring.caches, new); + if (old) { + call_rcu(old, virtio_free_region_cache, rcu); + } +} + /* virt queue functions */ void virtio_queue_update_rings(VirtIODevice *vdev, int n) { @@ -117,6 +170,7 @@ void virtio_queue_update_rings(VirtIODevice *vdev, int n) vring->used = vring_align(vring->avail + offsetof(VRingAvail, ring[vring->num]), vring->align); + virtio_init_region_cache(vdev, n); } static void vring_desc_read(VirtIODevice *vdev, VRingDesc *desc, @@ -1264,6 +1318,7 @@ void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc, vdev->vq[n].vring.desc = desc; vdev->vq[n].vring.avail = avail; vdev->vq[n].vring.used = used; + virtio_init_region_cache(vdev, n); } void virtio_queue_set_num(VirtIODevice *vdev, int n, int num) @@ -1984,9 +2039,6 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) void virtio_cleanup(VirtIODevice *vdev) { qemu_del_vm_change_state_handler(vdev->vmstate); - g_free(vdev->config); - g_free(vdev->vq); - g_free(vdev->vector_queues); } static void virtio_vmstate_change(void *opaque, int running, RunState state) @@ -2248,6 +2300,19 @@ void GCC_FMT_ATTR(2, 3) virtio_error(VirtIODevice *vdev, const char *fmt, ...) } } +static void virtio_memory_listener_commit(MemoryListener *listener) +{ + VirtIODevice *vdev = container_of(listener, VirtIODevice, listener); + int i; + + for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { + if (vdev->vq[i].vring.num == 0) { + break; + } + virtio_init_region_cache(vdev, i); + } +} + static void virtio_device_realize(DeviceState *dev, Error **errp) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); @@ -2270,6 +2335,9 @@ static void virtio_device_realize(DeviceState *dev, Error **errp) error_propagate(errp, err); return; } + + vdev->listener.commit = virtio_memory_listener_commit; + memory_listener_register(&vdev->listener, vdev->dma_as); } static void virtio_device_unrealize(DeviceState *dev, Error **errp) @@ -2292,6 +2360,36 @@ static void virtio_device_unrealize(DeviceState *dev, Error **errp) vdev->bus_name = NULL; } +static void virtio_device_free_virtqueues(VirtIODevice *vdev) +{ + int i; + if (!vdev->vq) { + return; + } + + for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { + VRingMemoryRegionCaches *caches; + if (vdev->vq[i].vring.num == 0) { + break; + } + caches = atomic_read(&vdev->vq[i].vring.caches); + atomic_set(&vdev->vq[i].vring.caches, NULL); + virtio_free_region_cache(caches); + } + g_free(vdev->vq); +} + +static void virtio_device_instance_finalize(Object *obj) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(obj); + + memory_listener_unregister(&vdev->listener); + virtio_device_free_virtqueues(vdev); + + g_free(vdev->config); + g_free(vdev->vector_queues); +} + static Property virtio_properties[] = { DEFINE_VIRTIO_COMMON_FEATURES(VirtIODevice, host_features), DEFINE_PROP_END_OF_LIST(), @@ -2418,6 +2516,7 @@ static const TypeInfo virtio_device_info = { .parent = TYPE_DEVICE, .instance_size = sizeof(VirtIODevice), .class_init = virtio_device_class_init, + .instance_finalize = virtio_device_instance_finalize, .abstract = true, .class_size = sizeof(VirtioDeviceClass), }; |