diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2013-07-09 13:19:18 +0300 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-08-02 22:14:52 +0200 |
| commit | 1e079ec5c16199e63c9c5e0e346a0fdf47681f32 (patch) | |
| tree | 0b1809dd5f7a761186dfd0030089435eeb4f9e6f /include | |
| parent | 2f92512982ce9672ec70838ac7f2eea4fdb1d534 (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>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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 4c069d8bd74..96c78437d32 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -96,6 +96,10 @@ 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); |