[dpdk-dev] [PATCH v5 04/13] vhost: add packed ring batch enqueue

[Marvin Liu]

Batch enqueue function will first check whether descriptors are cache
aligned. It will also check prerequisites in the beginning. Batch
enqueue function do not support chained mbufs, single packet enqueue
function will handle it.

Signed-off-by: Marvin Liu <yong.liu at intel.com>

diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 142c14e04..a8130dc06 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -881,6 +881,76 @@ virtio_dev_rx_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
 	return pkt_idx;
 }
 
+static __rte_unused int
+virtio_dev_rx_batch_packed(struct virtio_net *dev,
+			   struct vhost_virtqueue *vq,
+			   struct rte_mbuf **pkts)
+{
+	bool wrap_counter = vq->avail_wrap_counter;
+	struct vring_packed_desc *descs = vq->desc_packed;
+	uint16_t avail_idx = vq->last_avail_idx;
+	uint64_t desc_addrs[PACKED_BATCH_SIZE];
+	struct virtio_net_hdr_mrg_rxbuf *hdrs[PACKED_BATCH_SIZE];
+	uint32_t buf_offset = dev->vhost_hlen;
+	uint64_t lens[PACKED_BATCH_SIZE];
+	uint16_t i;
+
+	if (unlikely(avail_idx & PACKED_BATCH_MASK))
+		return -1;
+
+	if (unlikely((avail_idx + PACKED_BATCH_SIZE) > vq->size))
+		return -1;
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+		if (unlikely(pkts[i]->next != NULL))
+			return -1;
+		if (unlikely(!desc_is_avail(&descs[avail_idx + i],
+					    wrap_counter)))
+			return -1;
+	}
+
+	rte_smp_rmb();
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
+		lens[i] = descs[avail_idx + i].len;
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+		if (unlikely(pkts[i]->pkt_len > (lens[i] - buf_offset)))
+			return -1;
+	}
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
+		desc_addrs[i] = vhost_iova_to_vva(dev, vq,
+						  descs[avail_idx + i].addr,
+						  &lens[i],
+						  VHOST_ACCESS_RW);
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+		if (unlikely(lens[i] != descs[avail_idx + i].len))
+			return -1;
+	}
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+		rte_prefetch0((void *)(uintptr_t)desc_addrs[i]);
+		hdrs[i] = (struct virtio_net_hdr_mrg_rxbuf *)
+					(uintptr_t)desc_addrs[i];
+		lens[i] = pkts[i]->pkt_len + dev->vhost_hlen;
+	}
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
+		virtio_enqueue_offload(pkts[i], &hdrs[i]->hdr);
+
+	vq_inc_last_avail_packed(vq, PACKED_BATCH_SIZE);
+
+	for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+		rte_memcpy((void *)(uintptr_t)(desc_addrs[i] + buf_offset),
+			   rte_pktmbuf_mtod_offset(pkts[i], void *, 0),
+			   pkts[i]->pkt_len);
+	}
+
+	return 0;
+}
+
 static __rte_unused int16_t
 virtio_dev_rx_single_packed(struct virtio_net *dev,
 			    struct vhost_virtqueue *vq,
-- 
2.17.1