[dpdk-dev] [PATCH v6 05/13] vhost: add packed ring single dequeue

[Marvin Liu]

Add vhost single packet dequeue function for packed ring and meanwhile
left space for shadow used ring update function.

Signed-off-by: Marvin Liu <yong.liu at intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin at redhat.com>

diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index a8130dc06..e1b06c1ce 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -1551,6 +1551,61 @@ virtio_dev_tx_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
 	return i;
 }
 
+static __rte_always_inline int
+vhost_dequeue_single_packed(struct virtio_net *dev,
+			    struct vhost_virtqueue *vq,
+			    struct rte_mempool *mbuf_pool,
+			    struct rte_mbuf **pkts,
+			    uint16_t *buf_id,
+			    uint16_t *desc_count)
+{
+	struct buf_vector buf_vec[BUF_VECTOR_MAX];
+	uint32_t dummy_len;
+	uint16_t nr_vec = 0;
+	int err;
+
+	if (unlikely(fill_vec_buf_packed(dev, vq,
+					 vq->last_avail_idx, desc_count,
+					 buf_vec, &nr_vec,
+					 buf_id, &dummy_len,
+					 VHOST_ACCESS_RO) < 0))
+		return -1;
+
+	*pkts = rte_pktmbuf_alloc(mbuf_pool);
+	if (unlikely(*pkts == NULL)) {
+		RTE_LOG(ERR, VHOST_DATA,
+			"Failed to allocate memory for mbuf.\n");
+		return -1;
+	}
+
+	err = copy_desc_to_mbuf(dev, vq, buf_vec, nr_vec, *pkts,
+				mbuf_pool);
+	if (unlikely(err)) {
+		rte_pktmbuf_free(*pkts);
+		return -1;
+	}
+
+	return 0;
+}
+
+static __rte_unused int
+virtio_dev_tx_single_packed(struct virtio_net *dev,
+			    struct vhost_virtqueue *vq,
+			    struct rte_mempool *mbuf_pool,
+			    struct rte_mbuf **pkts)
+{
+
+	uint16_t buf_id, desc_count;
+
+	if (vhost_dequeue_single_packed(dev, vq, mbuf_pool, pkts, &buf_id,
+					&desc_count))
+		return -1;
+
+	vq_inc_last_avail_packed(vq, desc_count);
+
+	return 0;
+}
+
 static __rte_noinline uint16_t
 virtio_dev_tx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
 	struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count)
-- 
2.17.1