vhost: support event index
Support the new event index feature. When acked,
utilize it to reduce the # of interrupts sent to the guest.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index b3363ae..8e03379 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -84,6 +84,12 @@
/* Used flags */
u16 used_flags;
+ /* Last used index value we have signalled on */
+ u16 signalled_used;
+
+ /* Last used index value we have signalled on */
+ bool signalled_used_valid;
+
/* Log writes to used structure. */
bool log_used;
u64 log_addr;
@@ -149,8 +155,8 @@
void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
struct vring_used_elem *heads, unsigned count);
void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
-void vhost_disable_notify(struct vhost_virtqueue *);
-bool vhost_enable_notify(struct vhost_virtqueue *);
+void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
+bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
unsigned int log_num, u64 len);
@@ -162,11 +168,12 @@
} while (0)
enum {
- VHOST_FEATURES = (1 << VIRTIO_F_NOTIFY_ON_EMPTY) |
- (1 << VIRTIO_RING_F_INDIRECT_DESC) |
- (1 << VHOST_F_LOG_ALL) |
- (1 << VHOST_NET_F_VIRTIO_NET_HDR) |
- (1 << VIRTIO_NET_F_MRG_RXBUF),
+ VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
+ (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
+ (1ULL << VIRTIO_RING_F_EVENT_IDX) |
+ (1ULL << VHOST_F_LOG_ALL) |
+ (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) |
+ (1ULL << VIRTIO_NET_F_MRG_RXBUF),
};
static inline int vhost_has_feature(struct vhost_dev *dev, int bit)