Function tx_only_begin

dpdk/app/test-pmd/txonly.c:416–488

}

static int
tx_only_begin(portid_t pi)
{
	uint16_t pkt_hdr_len, pkt_data_len;
	int dynf;

	pkt_hdr_len = (uint16_t)(sizeof(struct rte_ether_hdr) +
				 sizeof(struct rte_ipv4_hdr) +
				 sizeof(struct rte_udp_hdr));
	pkt_data_len = tx_pkt_length - pkt_hdr_len;

	if ((tx_pkt_split == TX_PKT_SPLIT_RND || txonly_multi_flow) &&
	    tx_pkt_seg_lengths[0] < pkt_hdr_len) {
		TESTPMD_LOG(ERR,
			    "Random segment number or multiple flow is enabled, "
			    "but tx_pkt_seg_lengths[0] %u < %u (needed)\n",
			    tx_pkt_seg_lengths[0], pkt_hdr_len);
		return -EINVAL;
	}

	setup_pkt_udp_ip_headers(&pkt_ip_hdr, &pkt_udp_hdr, pkt_data_len);

	timestamp_enable = false;
	timestamp_mask = 0;
	timestamp_off = -1;
	dynf = rte_mbuf_dynflag_lookup
				(RTE_MBUF_DYNFLAG_TX_TIMESTAMP_NAME, NULL);
	if (dynf >= 0)
		timestamp_mask = 1ULL << dynf;
	dynf = rte_mbuf_dynfield_lookup
				(RTE_MBUF_DYNFIELD_TIMESTAMP_NAME, NULL);
	if (dynf >= 0)
		timestamp_off = dynf;
	timestamp_enable = tx_pkt_times_inter &&
			   timestamp_mask &&
			   timestamp_off >= 0 &&
			   !rte_eth_read_clock(pi, &timestamp_initial[pi]);

	if (timestamp_enable) {
		pkt_hdr_len += sizeof(struct tx_timestamp);

		if (tx_pkt_split == TX_PKT_SPLIT_RND) {
			if (tx_pkt_seg_lengths[0] < pkt_hdr_len) {
				TESTPMD_LOG(ERR,
					    "Time stamp and random segment number are enabled, "
					    "but tx_pkt_seg_lengths[0] %u < %u (needed)\n",
					    tx_pkt_seg_lengths[0], pkt_hdr_len);
				return -EINVAL;
			}
		} else {
			uint16_t total = 0;
			uint8_t i;

			for (i = 0; i < tx_pkt_nb_segs; i++) {
				total += tx_pkt_seg_lengths[i];
				if (total >= pkt_hdr_len)
					break;
			}