Function virtio_dev_tx_split

dpdk/lib/vhost/virtio_net.c:3103–3194

}

__rte_always_inline
static uint16_t
virtio_dev_tx_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
	struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count,
	bool legacy_ol_flags)
	__rte_shared_locks_required(&vq->access_lock)
	__rte_shared_locks_required(&vq->iotlb_lock)
{
	uint16_t i;
	uint16_t avail_entries;
	static bool allocerr_warned;

	/*
	 * The ordering between avail index and
	 * desc reads needs to be enforced.
	 */
	avail_entries = rte_atomic_load_explicit((unsigned short __rte_atomic *)&vq->avail->idx,
		rte_memory_order_acquire) - vq->last_avail_idx;
	if (avail_entries == 0)
		return 0;

	rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]);

	VHOST_LOG_DATA(dev->ifname, DEBUG, "%s\n", __func__);

	count = RTE_MIN(count, MAX_PKT_BURST);
	count = RTE_MIN(count, avail_entries);
	VHOST_LOG_DATA(dev->ifname, DEBUG, "about to dequeue %u buffers\n", count);

	if (rte_pktmbuf_alloc_bulk(mbuf_pool, pkts, count))
		return 0;

	for (i = 0; i < count; i++) {
		struct buf_vector buf_vec[BUF_VECTOR_MAX];
		uint16_t head_idx;
		uint32_t buf_len;
		uint16_t nr_vec = 0;
		int err;

		if (unlikely(fill_vec_buf_split(dev, vq,
						vq->last_avail_idx + i,
						&nr_vec, buf_vec,
						&head_idx, &buf_len,
						VHOST_ACCESS_RO) < 0))
			break;

		update_shadow_used_ring_split(vq, head_idx, 0);

		if (unlikely(buf_len <= dev->vhost_hlen))
			break;

		buf_len -= dev->vhost_hlen;

		err = virtio_dev_pktmbuf_prep(dev, pkts[i], buf_len);
		if (unlikely(err)) {
			/*
			 * mbuf allocation fails for jumbo packets when external
			 * buffer allocation is not allowed and linear buffer