+
+/**
+ * TCP segmentation offload. To enable this offload feature for a
+ * packet to be transmitted on hardware supporting TSO:
+ * - set the PKT_TX_TCP_SEG flag in mbuf->ol_flags (this flag implies
+ * PKT_TX_TCP_CKSUM)
+ * - set the flag PKT_TX_IPV4 or PKT_TX_IPV6
+ * - if it's IPv4, set the PKT_TX_IP_CKSUM flag and write the IP checksum
+ * to 0 in the packet
+ * - fill the mbuf offload information: l2_len, l3_len, l4_len, tso_segsz
+ * - calculate the pseudo header checksum without taking ip_len in account,
+ * and set it in the TCP header. Refer to rte_ipv4_phdr_cksum() and
+ * rte_ipv6_phdr_cksum() that can be used as helpers.
+ */
+#define PKT_TX_TCP_SEG (1ULL << 49)
+