[dpdk-dev] [PATCH v6 14/15] vhost: add notification for packed ring
Maxime Coquelin
maxime.coquelin at redhat.com
Wed Jul 4 18:02:18 CEST 2018
On 07/03/2018 08:06 AM, Jason Wang wrote:
>
>
> On 2018年07月02日 16:16, Maxime Coquelin wrote:
>> Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
>> ---
>> lib/librte_vhost/vhost.c | 73
>> ++++++++++++++++++++++++++++++++++++----
>> lib/librte_vhost/vhost.h | 71
>> ++++++++++++++++++++++++++++++++++----
>> lib/librte_vhost/vhost_user.c | 24 +++++++++++++
>> lib/librte_vhost/virtio-packed.h | 11 ++++++
>> lib/librte_vhost/virtio_net.c | 12 +++----
>> 5 files changed, 172 insertions(+), 19 deletions(-)
>>
>> diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
>> index 8538302c9..78f20c402 100644
>> --- a/lib/librte_vhost/vhost.c
>> +++ b/lib/librte_vhost/vhost.c
>> @@ -171,6 +171,24 @@ vring_translate_packed(struct virtio_net *dev,
>> struct vhost_virtqueue *vq)
>> 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;
>> }
>> @@ -595,7 +613,11 @@ 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;
>> }
>> @@ -616,20 +638,59 @@ rte_vhost_avail_entries(int vid, uint16_t queue_id)
>> return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx;
>> }
>> +static inline int
>> +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;
>> +
>> + return 0;
>> +}
>> +
>> +static inline int
>> +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 = RING_EVENT_FLAGS_DISABLE;
>> + return 0;
>> + }
>> +
>> + flags = RING_EVENT_FLAGS_ENABLE;
>> + if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
>> + flags = RING_EVENT_FLAGS_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;
>> +
>> + rte_smp_wmb();
>> +
>> + return 0;
>> +}
>> +
>> 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))
>> + return vhost_enable_notify_packed(dev, vq, enable);
>> else
>> - dev->virtqueue[queue_id]->used->flags |= VRING_USED_F_NO_NOTIFY;
>> - return 0;
>> + return vhost_enable_notify_split(vq, enable);
>> }
>> void
>> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
>> index 6ea8fb896..728fd2f6b 100644
>> --- a/lib/librte_vhost/vhost.h
>> +++ b/lib/librte_vhost/vhost.h
>> @@ -21,6 +21,7 @@
>> #include "rte_vhost.h"
>> #include "rte_vdpa.h"
>> +#include "virtio-packed.h"
>> /* Used to indicate that the device is running on a data core */
>> #define VIRTIO_DEV_RUNNING 1
>> @@ -95,8 +96,14 @@ 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;
>> @@ -613,7 +620,7 @@ 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_mb();
>> @@ -624,11 +631,11 @@ vhost_vring_call(struct virtio_net *dev, struct
>> vhost_virtqueue *vq)
>> uint16_t new = vq->last_used_idx;
>> VHOST_LOG_DEBUG(VHOST_DATA, "%s: used_event_idx=%d, old=%d,
>> new=%d\n",
>> - __func__,
>> - vhost_used_event(vq),
>> - old, new);
>> + __func__,
>> + vhost_used_event(vq),
>> + old, new);
>> if (vhost_need_event(vhost_used_event(vq), new, old)
>> - && (vq->callfd >= 0)) {
>> + && (vq->callfd >= 0)) {
>> vq->signalled_used = vq->last_used_idx;
>> eventfd_write(vq->callfd, (eventfd_t) 1);
>> }
>
> Looks like a style fixes, move those to another patch?
Indeed, I'll remove this style fixes in next version.
>> @@ -640,4 +647,54 @@ 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, 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 !=
>> + RING_EVENT_FLAGS_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 != RING_EVENT_FLAGS_DESC) {
>> + if (vq->driver_event->desc_event_flags !=
>> + RING_EVENT_FLAGS_DISABLE)
>> + kick = true;
>> + goto kick;
>> + }
>> +
>> + rte_smp_rmb();
>> +
>> + off_wrap = vq->driver_event->desc_event_off_wrap;
>> + off = off_wrap & ~(1 << 15);
>> + wrap = vq->used_wrap_counter;
>> +
>> + if (new < old) {
>> + new += vq->size;
>> + wrap ^= 1;
>> + }
>> +
>> + if (wrap != off_wrap >> 15)
>> + off += vq->size;
>> +
>
> Jusy FYI. Maybe we can switch to a more compact version like Tiwei used:
>
> ...
> wrap_counter = off_wrap >> 15;
> event_idx = off_wrap & ~(1<<15);
> if (wrap_counter != vq->avail_wrap_counter)
> event_idx -= vq->vring_packed.num;
>
> if (flags == VRING_EVENT_F_DESC)
> needs_kick = vring_need_event(event_idx, new, old);
> else
> needs_kick = (flags != VRING_EVENT_F_DISABLE);
>
> (I've switched to this version in vhost).
Sure, it is indeed simpler.
Thanks,
Maxime
> Thanks
>
>> + 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 b2b57de57..bda515bdb 100644
>> --- a/lib/librte_vhost/vhost_user.c
>> +++ b/lib/librte_vhost/vhost_user.c
>> @@ -523,6 +523,30 @@ 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 == 0 ||
>> + 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 == 0 ||
>> + 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-packed.h
>> b/lib/librte_vhost/virtio-packed.h
>> index d386cb6df..ce3b28313 100644
>> --- a/lib/librte_vhost/virtio-packed.h
>> +++ b/lib/librte_vhost/virtio-packed.h
>> @@ -19,6 +19,17 @@ struct vring_desc_packed {
>> uint16_t flags;
>> };
>> +#define RING_EVENT_FLAGS_ENABLE 0x0
>> +#define RING_EVENT_FLAGS_DISABLE 0x1
>> +#define RING_EVENT_FLAGS_DESC 0x2
>> +#define RING_EVENT_FLAGS_MASK 0xFFFC
>> +#define RING_EVENT_WRAP_MASK 0x8000
>> +#define RING_EVENT_OFF_MASK 0x7FFF
>> +
>> +struct vring_packed_desc_event {
>> + uint16_t desc_event_off_wrap;
>> + uint16_t desc_event_flags;
>> +};
>> static inline bool
>> desc_is_avail(struct vring_desc_packed *desc, bool wrap_counter)
>> diff --git a/lib/librte_vhost/virtio_net.c
>> b/lib/librte_vhost/virtio_net.c
>> index 03dd38235..11c10aaf8 100644
>> --- a/lib/librte_vhost/virtio_net.c
>> +++ b/lib/librte_vhost/virtio_net.c
>> @@ -824,7 +824,7 @@ 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;
>> @@ -877,7 +877,7 @@ 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;
>> @@ -1360,7 +1360,7 @@ 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)]);
>> @@ -1439,7 +1439,7 @@ 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;
>
More information about the dev
mailing list