vhost: add Rx support for packed ring

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Tiwei Bie <tiwei.bie@intel.com>

diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 2b6ab3c..904981f 100644 (file)
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -130,7 +130,7 @@ update_shadow_used_ring_split(struct vhost_virtqueue *vq,
        vq->shadow_used_split[i].len = len;
 }
 
-static __rte_unused __rte_always_inline void
+static __rte_always_inline void
 flush_shadow_used_ring_packed(struct virtio_net *dev,
                        struct vhost_virtqueue *vq)
 {
@@ -184,7 +184,7 @@ flush_shadow_used_ring_packed(struct virtio_net *dev,
        vhost_log_cache_sync(dev, vq);
 }
 
-static __rte_unused __rte_always_inline void
+static __rte_always_inline void
 update_shadow_used_ring_packed(struct vhost_virtqueue *vq,
                         uint16_t desc_idx, uint16_t len, uint16_t count)
 {
@@ -506,7 +506,7 @@ fill_vec_buf_packed_indirect(struct virtio_net *dev,
        return 0;
 }
 
-static __rte_unused __rte_always_inline int
+static __rte_always_inline int
 fill_vec_buf_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
                                uint16_t avail_idx, uint16_t *desc_count,
                                struct buf_vector *buf_vec, uint16_t *vec_idx,
@@ -561,6 +561,65 @@ fill_vec_buf_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
        return 0;
 }
 
+/*
+ * Returns -1 on fail, 0 on success
+ */
+static inline int
+reserve_avail_buf_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
+                               uint32_t size, struct buf_vector *buf_vec,
+                               uint16_t *nr_vec, uint16_t *num_buffers,
+                               uint16_t *nr_descs)
+{
+       uint16_t avail_idx;
+       uint16_t vec_idx = 0;
+       uint16_t max_tries, tries = 0;
+
+       uint16_t buf_id = 0;
+       uint16_t len = 0;
+       uint16_t desc_count;
+
+       *num_buffers = 0;
+       avail_idx = vq->last_avail_idx;
+
+       if (rxvq_is_mergeable(dev))
+               max_tries = vq->size;
+       else
+               max_tries = 1;
+
+       while (size > 0) {
+               if (unlikely(fill_vec_buf_packed(dev, vq,
+                                               avail_idx, &desc_count,
+                                               buf_vec, &vec_idx,
+                                               &buf_id, &len,
+                                               VHOST_ACCESS_RO) < 0))
+                       return -1;
+
+               len = RTE_MIN(len, size);
+               update_shadow_used_ring_packed(vq, buf_id, len, desc_count);
+               size -= len;
+
+               avail_idx += desc_count;
+               if (avail_idx >= vq->size)
+                       avail_idx -= vq->size;
+
+               *nr_descs += desc_count;
+               tries++;
+               *num_buffers += 1;
+
+               /*
+                * if we tried all available ring items, and still
+                * can't get enough buf, it means something abnormal
+                * happened.
+                */
+               if (unlikely(tries > max_tries))
+                       return -1;
+       }
+
+       *nr_vec = vec_idx;
+
+       return 0;
+}
+
 static __rte_always_inline int
 copy_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq,
                            struct rte_mbuf *m, struct buf_vector *buf_vec,
@@ -773,6 +832,59 @@ virtio_dev_rx_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
        return pkt_idx;
 }
 
+static __rte_always_inline uint32_t
+virtio_dev_rx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
+       struct rte_mbuf **pkts, uint32_t count)
+{
+       uint32_t pkt_idx = 0;
+       uint16_t num_buffers;
+       struct buf_vector buf_vec[BUF_VECTOR_MAX];
+
+       for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
+               uint32_t pkt_len = pkts[pkt_idx]->pkt_len + dev->vhost_hlen;
+               uint16_t nr_vec = 0;
+               uint16_t nr_descs = 0;
+
+               if (unlikely(reserve_avail_buf_packed(dev, vq,
+                                               pkt_len, buf_vec, &nr_vec,
+                                               &num_buffers, &nr_descs) < 0)) {
+                       VHOST_LOG_DEBUG(VHOST_DATA,
+                               "(%d) failed to get enough desc from vring\n",
+                               dev->vid);
+                       vq->shadow_used_idx -= num_buffers;
+                       break;
+               }
+
+               rte_prefetch0((void *)(uintptr_t)buf_vec[0].buf_addr);
+
+               VHOST_LOG_DEBUG(VHOST_DATA, "(%d) current index %d | end index %d\n",
+                       dev->vid, vq->last_avail_idx,
+                       vq->last_avail_idx + num_buffers);
+
+               if (copy_mbuf_to_desc(dev, vq, pkts[pkt_idx],
+                                               buf_vec, nr_vec,
+                                               num_buffers) < 0) {
+                       vq->shadow_used_idx -= num_buffers;
+                       break;
+               }
+
+               vq->last_avail_idx += nr_descs;
+               if (vq->last_avail_idx >= vq->size) {
+                       vq->last_avail_idx -= vq->size;
+                       vq->avail_wrap_counter ^= 1;
+               }
+       }
+
+       do_data_copy_enqueue(dev, vq);
+
+       if (likely(vq->shadow_used_idx)) {
+               flush_shadow_used_ring_packed(dev, vq);
+               vhost_vring_call(dev, vq);
+       }
+
+       return pkt_idx;
+}
+
 static __rte_always_inline uint32_t
 virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
        struct rte_mbuf **pkts, uint32_t count)
@@ -804,7 +916,10 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
        if (count == 0)
                goto out;
 
-       count = virtio_dev_rx_split(dev, vq, pkts, count);
+       if (vq_is_packed(dev))
+               count = virtio_dev_rx_packed(dev, vq, pkts, count);
+       else
+               count = virtio_dev_rx_split(dev, vq, pkts, count);
 
 out:
        if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))