diff mbox series

[v8,14/15] vhost: add notification for packed ring

Message ID 20180705210741.17974-15-maxime.coquelin@redhat.com (mailing list archive)
State Superseded, archived
Delegated to: Maxime Coquelin
Headers show
Series Vhost: add support to packed ring layout | expand

Checks

Context Check Description
ci/Intel-compilation fail Compilation issues

Commit Message

Maxime Coquelin July 5, 2018, 9:07 p.m. UTC
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 lib/librte_vhost/vhost.c      | 71 +++++++++++++++++++++++++++++++++++------
 lib/librte_vhost/vhost.h      | 73 +++++++++++++++++++++++++++++++++++++++++--
 lib/librte_vhost/vhost_user.c | 24 ++++++++++++++
 lib/librte_vhost/virtio_net.c | 12 +++----
 4 files changed, 162 insertions(+), 18 deletions(-)
diff mbox series

Patch

diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index b5c649281..eb32e91c7 100644
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -163,13 +163,28 @@  vring_translate_packed(struct virtio_net *dev, struct vhost_virtqueue *vq)
 
 	req_size = sizeof(struct vring_desc_packed) * vq->size;
 	size = req_size;
-	vq->desc_packed =
-		(struct vring_desc_packed *)(uintptr_t)vhost_iova_to_vva(dev,
-					vq, vq->ring_addrs.desc_user_addr,
-					&size, VHOST_ACCESS_RW);
+	vq->desc_packed = (struct vring_desc_packed *)(uintptr_t)
+		vhost_iova_to_vva(dev, vq, vq->ring_addrs.desc_user_addr,
+				&size, VHOST_ACCESS_RW);
 	if (!vq->desc_packed || size != req_size)
 		return -1;
 
+	req_size = sizeof(struct vring_packed_desc_event);
+	size = req_size;
+	vq->driver_event = (struct vring_packed_desc_event *)(uintptr_t)
+		vhost_iova_to_vva(dev, vq, vq->ring_addrs.avail_user_addr,
+				&size, VHOST_ACCESS_RW);
+	if (!vq->driver_event || size != req_size)
+		return -1;
+
+	req_size = sizeof(struct vring_packed_desc_event);
+	size = req_size;
+	vq->device_event = (struct vring_packed_desc_event *)(uintptr_t)
+		vhost_iova_to_vva(dev, vq, vq->ring_addrs.used_user_addr,
+				&size, VHOST_ACCESS_RW);
+	if (!vq->device_event || size != req_size)
+		return -1;
+
 	return 0;
 }
 
@@ -270,6 +285,7 @@  alloc_vring_queue(struct virtio_net *dev, uint32_t vring_idx)
 	rte_spinlock_init(&vq->access_lock);
 	vq->avail_wrap_counter = 1;
 	vq->used_wrap_counter = 1;
+	vq->signalled_used_valid = false;
 
 	dev->nr_vring += 1;
 
@@ -604,7 +620,11 @@  rte_vhost_vring_call(int vid, uint16_t vring_idx)
 	if (!vq)
 		return -1;
 
-	vhost_vring_call(dev, vq);
+	if (vq_is_packed(dev))
+		vhost_vring_call_packed(dev, vq);
+	else
+		vhost_vring_call_split(dev, vq);
+
 	return 0;
 }
 
@@ -625,19 +645,52 @@  rte_vhost_avail_entries(int vid, uint16_t queue_id)
 	return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx;
 }
 
+static inline void
+vhost_enable_notify_split(struct vhost_virtqueue *vq, int enable)
+{
+	if (enable)
+		vq->used->flags &= ~VRING_USED_F_NO_NOTIFY;
+	else
+		vq->used->flags |= VRING_USED_F_NO_NOTIFY;
+}
+
+static inline void
+vhost_enable_notify_packed(struct virtio_net *dev,
+		struct vhost_virtqueue *vq, int enable)
+{
+	uint16_t flags;
+
+	if (!enable)
+		vq->device_event->flags = VRING_EVENT_F_DISABLE;
+
+	flags = VRING_EVENT_F_ENABLE;
+	if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
+		flags = VRING_EVENT_F_DESC;
+		vq->device_event->off_wrap = vq->last_avail_idx |
+			vq->avail_wrap_counter << 15;
+	}
+
+	rte_smp_wmb();
+
+	vq->device_event->flags = flags;
+}
+
 int
 rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable)
 {
 	struct virtio_net *dev = get_device(vid);
+	struct vhost_virtqueue *vq;
 
 	if (!dev)
 		return -1;
 
-	if (enable)
-		dev->virtqueue[queue_id]->used->flags &=
-			~VRING_USED_F_NO_NOTIFY;
+	vq = dev->virtqueue[queue_id];
+
+	if (vq_is_packed(dev))
+		vhost_enable_notify_packed(dev, vq, enable);
 	else
-		dev->virtqueue[queue_id]->used->flags |= VRING_USED_F_NO_NOTIFY;
+		vhost_enable_notify_split(vq, enable);
+
 	return 0;
 }
 
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index a18c63cad..3daa6e7d0 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -95,14 +95,21 @@  struct vhost_virtqueue {
 		struct vring_desc	*desc;
 		struct vring_desc_packed   *desc_packed;
 	};
-	struct vring_avail	*avail;
-	struct vring_used	*used;
+	union {
+		struct vring_avail	*avail;
+		struct vring_packed_desc_event *driver_event;
+	};
+	union {
+		struct vring_used	*used;
+		struct vring_packed_desc_event *device_event;
+	};
 	uint32_t		size;
 
 	uint16_t		last_avail_idx;
 	uint16_t		last_used_idx;
 	/* Last used index we notify to front end. */
 	uint16_t		signalled_used;
+	bool			signalled_used_valid;
 #define VIRTIO_INVALID_EVENTFD		(-1)
 #define VIRTIO_UNINITIALIZED_EVENTFD	(-2)
 
@@ -225,6 +232,15 @@  struct vring_desc_packed {
 	uint16_t id;
 	uint16_t flags;
 };
+
+#define VRING_EVENT_F_ENABLE 0x0
+#define VRING_EVENT_F_DISABLE 0x1
+#define VRING_EVENT_F_DESC 0x2
+
+struct vring_packed_desc_event {
+	uint16_t off_wrap;
+	uint16_t flags;
+};
 #endif
 
 /*
@@ -648,7 +664,7 @@  vhost_need_event(uint16_t event_idx, uint16_t new_idx, uint16_t old)
 }
 
 static __rte_always_inline void
-vhost_vring_call(struct virtio_net *dev, struct vhost_virtqueue *vq)
+vhost_vring_call_split(struct virtio_net *dev, struct vhost_virtqueue *vq)
 {
 	/* Flush used->idx update before we read avail->flags. */
 	rte_smp_mb();
@@ -675,4 +691,55 @@  vhost_vring_call(struct virtio_net *dev, struct vhost_virtqueue *vq)
 	}
 }
 
+static __rte_always_inline void
+vhost_vring_call_packed(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+	uint16_t old, new, off, off_wrap;
+	bool signalled_used_valid, kick = false;
+
+	/* Flush used desc update. */
+	rte_smp_mb();
+
+	if (!(dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))) {
+		if (vq->driver_event->flags !=
+				VRING_EVENT_F_DISABLE)
+			kick = true;
+		goto kick;
+	}
+
+	old = vq->signalled_used;
+	new = vq->last_used_idx;
+	vq->signalled_used = new;
+	signalled_used_valid = vq->signalled_used_valid;
+	vq->signalled_used_valid = true;
+
+	if (vq->driver_event->flags != VRING_EVENT_F_DESC) {
+		if (vq->driver_event->flags != VRING_EVENT_F_DISABLE)
+			kick = true;
+		goto kick;
+	}
+
+	if (unlikely(!signalled_used_valid)) {
+		kick = true;
+		goto kick;
+	}
+
+	rte_smp_rmb();
+
+	off_wrap = vq->driver_event->off_wrap;
+	off = off_wrap & ~(1 << 15);
+
+	if (new <= old)
+		old -= vq->size;
+
+	if (vq->used_wrap_counter != off_wrap >> 15)
+		off -= vq->size;
+
+	if (vhost_need_event(off, new, old))
+		kick = true;
+kick:
+	if (kick)
+		eventfd_write(vq->callfd, (eventfd_t)1);
+}
+
 #endif /* _VHOST_NET_CDEV_H_ */
diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 4ad7c3e55..4fa8dbad3 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -512,6 +512,30 @@  translate_ring_addresses(struct virtio_net *dev, int vq_index)
 		vq = dev->virtqueue[vq_index];
 		addr = &vq->ring_addrs;
 
+		len = sizeof(struct vring_packed_desc_event);
+		vq->driver_event = (struct vring_packed_desc_event *)
+					(uintptr_t)ring_addr_to_vva(dev,
+					vq, addr->avail_user_addr, &len);
+		if (vq->driver_event == NULL ||
+				len != sizeof(struct vring_packed_desc_event)) {
+			RTE_LOG(DEBUG, VHOST_CONFIG,
+				"(%d) failed to find driver area address.\n",
+				dev->vid);
+			return dev;
+		}
+
+		len = sizeof(struct vring_packed_desc_event);
+		vq->device_event = (struct vring_packed_desc_event *)
+					(uintptr_t)ring_addr_to_vva(dev,
+					vq, addr->used_user_addr, &len);
+		if (vq->device_event == NULL ||
+				len != sizeof(struct vring_packed_desc_event)) {
+			RTE_LOG(DEBUG, VHOST_CONFIG,
+				"(%d) failed to find device area address.\n",
+				dev->vid);
+			return dev;
+		}
+
 		return dev;
 	}
 
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index e79a82f45..ccdf73cf4 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -826,7 +826,7 @@  virtio_dev_rx_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
 
 	if (likely(vq->shadow_used_idx)) {
 		flush_shadow_used_ring_split(dev, vq);
-		vhost_vring_call(dev, vq);
+		vhost_vring_call_split(dev, vq);
 	}
 
 	return pkt_idx;
@@ -879,7 +879,7 @@  virtio_dev_rx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
 
 	if (likely(vq->shadow_used_idx)) {
 		flush_shadow_used_ring_packed(dev, vq);
-		vhost_vring_call(dev, vq);
+		vhost_vring_call_packed(dev, vq);
 	}
 
 	return pkt_idx;
@@ -1362,7 +1362,7 @@  virtio_dev_tx_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
 		}
 
 		flush_shadow_used_ring_split(dev, vq);
-		vhost_vring_call(dev, vq);
+		vhost_vring_call_split(dev, vq);
 	}
 
 	rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]);
@@ -1441,7 +1441,7 @@  virtio_dev_tx_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
 		if (unlikely(i < count))
 			vq->shadow_used_idx = i;
 		flush_shadow_used_ring_split(dev, vq);
-		vhost_vring_call(dev, vq);
+		vhost_vring_call_split(dev, vq);
 	}
 
 	return i;
@@ -1477,7 +1477,7 @@  virtio_dev_tx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
 		}
 
 		flush_shadow_used_ring_packed(dev, vq);
-		vhost_vring_call(dev, vq);
+		vhost_vring_call_packed(dev, vq);
 	}
 
 	VHOST_LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__);
@@ -1555,7 +1555,7 @@  virtio_dev_tx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
 		if (unlikely(i < count))
 			vq->shadow_used_idx = i;
 		flush_shadow_used_ring_packed(dev, vq);
-		vhost_vring_call(dev, vq);
+		vhost_vring_call_packed(dev, vq);
 	}
 
 	return i;