* sum(delta(snd_una)), or how many bytes
* were acked.
*/
+ struct u64_stats_sync syncp; /* protects 64bit vars (cf tcp_get_info()) */
+
u32 snd_una; /* First byte we want an ack for */
u32 snd_sml; /* Last byte of the most recently transmitted small packet */
u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */