path: root/include
diff options
authorMichael S. Tsirkin <>2013-07-09 13:19:18 +0300
committerGreg Kroah-Hartman <>2013-07-28 16:29:55 -0700
commitc23b1ece6112ed0f227fdc881db33c6427b65222 (patch)
treeafe12ef05dbfdbd96e31e233ce78866d1f33081a /include
parentd1a2a1a6efee375e9ac00ec0a718503fd05b4302 (diff)
virtio: support unlocked queue poll
[ Upstream commit cc229884d3f77ec3b1240e467e0236c3e0647c0c ] This adds a way to check ring empty state after enable_cb outside any locks. Will be used by virtio_net. Note: there's room for more optimization: caller is likely to have a memory barrier already, which means we might be able to get rid of a barrier here. Deferring this optimization until we do some benchmarking. Signed-off-by: Michael S. Tsirkin <> Signed-off-by: David S. Miller <> Signed-off-by: Greg Kroah-Hartman <>
Diffstat (limited to 'include')
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index 9ff8645b7e0b..72398eea6e86 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -70,6 +70,10 @@ void virtqueue_disable_cb(struct virtqueue *vq);
bool virtqueue_enable_cb(struct virtqueue *vq);
+unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq);
+bool virtqueue_poll(struct virtqueue *vq, unsigned);
bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
void *virtqueue_detach_unused_buf(struct virtqueue *vq);