tcp_stamp_us_delta
return tcp_stamp_us_delta(tp->tcp_mstamp, tp->accecn_opt_tstamp) * ecn_beacon >=
tcp_stamp_us_delta(tp->delivered_mstamp, bbr->cycle_mstamp) >
epoch_us = tcp_stamp_us_delta(tp->delivered_mstamp,
rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, xmit_time);
ack_us = tcp_stamp_us_delta(tp->tcp_mstamp,
rs->interval_us = tcp_stamp_us_delta(tp->first_tx_mstamp,
rtt_us = tcp_stamp_us_delta(tcp_clock_us(), tcp_rsk(req)->snt_synack);
seq_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, first_ackt);
ca_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, last_ackt);
sack_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, sack->first_sackt);
ca_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, sack->last_sackt);
sack_rtt_us > tcp_stamp_us_delta(tp->tcp_mstamp,
delta_us = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcv_rtt_est.time);
time = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcvq_space.time);
tcp_stamp_us_delta(tp->tcp_mstamp, tcp_skb_timestamp_us(skb));
time = tcp_stamp_us_delta(mstamp, READ_ONCE(msk->rcvq_space.time));