diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2013-07-09 13:19:18 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-04 16:26:03 +0800 |
| commit | 2010fa31f8f5c5fa8385459dff03cb844cf79dd1 (patch) | |
| tree | f43541e0f5a5169293e2094c5a722f289a96a33d /include | |
| parent | c733e1a2c459c09fe2510bfa49e2571b532be97c (diff) | |
virtio: support unlocked queue poll
commit cc229884d3f77ec3b1240e467e0236c3e0647c0c upstream.
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 <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[wg: Backported to 3.2]
Signed-off-by: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
[bwh: Backported to 3.4: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/virtio.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 8efd28ae559..2b779bf80cc 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -44,6 +44,10 @@ 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); |