TCPT_KEEP
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle);
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle);
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepinit);
if (!callout_expired(&tp->t_timer[TCPT_KEEP])) {
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepintvl);
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle);
PRU_SLOWTIMO | (TCPT_KEEP << 8));
TCP_TIMER_DISARM(tp, TCPT_KEEP);
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepinit);
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepintvl);
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle);
TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepinit);