On Wed, Jul 04, 2018 at 11:54:37PM +0200, Maxime Coquelin wrote:
[...]
> @@ -225,6 +231,15 @@ struct vring_desc_packed {
> uint16_t index;
> 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 desc_event_off_wrap;
> + uint16_t desc_event_flags;
> +};
As all above types (including struct vring_desc_packed)
and macros are being protected by VIRTIO_F_RING_PACKED,
and they won't be defined if VIRTIO_F_RING_PACKED is
defined in kernel header. We may want to unify the names.
For the types, we may have below types defined in
linux uapi:
struct vring_packed;
struct vring_packed_desc;
struct vring_packed_desc_event;
They can also be named as:
struct vring_packed;
struct vring_desc_packed;
struct vring_packed_desc_event;
We need to choose one of them or something else.
For the `struct vring_packed_desc_event`, it can
be defined as:
struct vring_packed_desc_event {
uint16_t off_wrap;
uint16_t flags;
};
or
struct vring_packed_desc_event {
uint16_t desc_event_off_wrap;
uint16_t desc_event_flags;
};
We need to choose one of them or something else.
For the `struct vring_packed_desc`, it can be
defined as:
struct vring_packed_desc {
uint64_t addr;
uint32_t len;
uint16_t index;
uint16_t flags;
};
or
struct vring_packed_desc {
uint64_t addr;
uint32_t len;
uint16_t id; // index -> id
uint16_t flags;
};
We need to choose one of them or something else.
> #endif
>
[...]
> +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 kick = false;
> +
> + /* Flush used desc update. */
> + rte_smp_mb();
> +
> + if (!(dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))) {
> + if (vq->driver_event->desc_event_flags !=
> + VRING_EVENT_F_DISABLE)
> + kick = true;
> + goto kick;
> + }
> +
> + old = vq->signalled_used;
We also need to check whether vq->signalled_used is valid?
> + new = vq->last_used_idx;
> + vq->signalled_used = new;
> +
> + if (vq->driver_event->desc_event_flags != VRING_EVENT_F_DESC) {
> + if (vq->driver_event->desc_event_flags !=
> + VRING_EVENT_F_DISABLE)
> + kick = true;
> + goto kick;
> + }
> +
> + rte_smp_rmb();
> +
> + off_wrap = vq->driver_event->desc_event_off_wrap;
> + off = off_wrap & ~(1 << 15);
> +
> + if (vq->used_wrap_counter != off_wrap >> 15)
> + off -= vq->size;
> +
> + if (vhost_need_event(off, new, old))
> + kick = true;
If new <= old, old needs to -= vq->size?
> +kick:
> + if (kick)
> + eventfd_write(vq->callfd, (eventfd_t)1);
> +}
> +
[...]
On 07/05/2018 07:12 AM, Tiwei Bie wrote:
> On Wed, Jul 04, 2018 at 11:54:37PM +0200, Maxime Coquelin wrote:
> [...]
>> @@ -225,6 +231,15 @@ struct vring_desc_packed {
>> uint16_t index;
>> 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 desc_event_off_wrap;
>> + uint16_t desc_event_flags;
>> +};
>
> As all above types (including struct vring_desc_packed)
> and macros are being protected by VIRTIO_F_RING_PACKED,
> and they won't be defined if VIRTIO_F_RING_PACKED is
> defined in kernel header. We may want to unify the names.
>
> For the types, we may have below types defined in
> linux uapi:
>
> struct vring_packed;
> struct vring_packed_desc;
> struct vring_packed_desc_event;
>
> They can also be named as:
>
> struct vring_packed;
> struct vring_desc_packed;
> struct vring_packed_desc_event;
>
> We need to choose one of them or something else.
>
> For the `struct vring_packed_desc_event`, it can
> be defined as:
>
> struct vring_packed_desc_event {
> uint16_t off_wrap;
> uint16_t flags;
> };
>
> or
>
> struct vring_packed_desc_event {
> uint16_t desc_event_off_wrap;
> uint16_t desc_event_flags;
> };
>
> We need to choose one of them or something else.
>
> For the `struct vring_packed_desc`, it can be
> defined as:
>
> struct vring_packed_desc {
> uint64_t addr;
> uint32_t len;
> uint16_t index;
> uint16_t flags;
> };
>
> or
>
> struct vring_packed_desc {
> uint64_t addr;
> uint32_t len;
> uint16_t id; // index -> id
> uint16_t flags;
> };
>
> We need to choose one of them or something else.
>
I will align on Kernel header.
>> #endif
>>
> [...]
>> +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 kick = false;
>> +
>> + /* Flush used desc update. */
>> + rte_smp_mb();
>> +
>> + if (!(dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))) {
>> + if (vq->driver_event->desc_event_flags !=
>> + VRING_EVENT_F_DISABLE)
>> + kick = true;
>> + goto kick;
>> + }
>> +
>> + old = vq->signalled_used;
>
> We also need to check whether vq->signalled_used is valid?
Yes, thanks for pointing this out.
So if not valid, I'll kick if desc_event_flags != VRING_EVENT_F_DISABLE.
>> + new = vq->last_used_idx;
>> + vq->signalled_used = new;
>> +
>> + if (vq->driver_event->desc_event_flags != VRING_EVENT_F_DESC) {
>> + if (vq->driver_event->desc_event_flags !=
>> + VRING_EVENT_F_DISABLE)
>> + kick = true;
>> + goto kick;
>> + }
>> +
>> + rte_smp_rmb();
>> +
>> + off_wrap = vq->driver_event->desc_event_off_wrap;
>> + off = off_wrap & ~(1 << 15);
>> +
>> + if (vq->used_wrap_counter != off_wrap >> 15)
>> + off -= vq->size;
>> +
>> + if (vhost_need_event(off, new, old))
>> + kick = true;
>
> If new <= old, old needs to -= vq->size?
Right, I'll fix it in next version.
Thanks!
Maxime
>> +kick:
>> + if (kick)
>> + eventfd_write(vq->callfd, (eventfd_t)1);
>> +}
>> +
> [...]
>
@@ -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;
}
@@ -604,7 +619,11 @@ 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 +644,52 @@ 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->desc_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->desc_event_off_wrap = vq->last_avail_idx |
+ vq->avail_wrap_counter << 15;
+ }
+
+ rte_smp_wmb();
+
+ vq->device_event->desc_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;
}
@@ -95,8 +95,14 @@ 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;
@@ -225,6 +231,15 @@ struct vring_desc_packed {
uint16_t index;
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 desc_event_off_wrap;
+ uint16_t desc_event_flags;
+};
#endif
/*
@@ -648,7 +663,7 @@ 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 +690,46 @@ 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 kick = false;
+
+ /* Flush used desc update. */
+ rte_smp_mb();
+
+ if (!(dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))) {
+ if (vq->driver_event->desc_event_flags !=
+ VRING_EVENT_F_DISABLE)
+ kick = true;
+ goto kick;
+ }
+
+ old = vq->signalled_used;
+ new = vq->last_used_idx;
+ vq->signalled_used = new;
+
+ if (vq->driver_event->desc_event_flags != VRING_EVENT_F_DESC) {
+ if (vq->driver_event->desc_event_flags !=
+ VRING_EVENT_F_DISABLE)
+ kick = true;
+ goto kick;
+ }
+
+ rte_smp_rmb();
+
+ off_wrap = vq->driver_event->desc_event_off_wrap;
+ off = off_wrap & ~(1 << 15);
+
+ 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_ */
@@ -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;
}
@@ -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;