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Differential D18960 Diff 54177 sys/netinet/tcp_stacks/fastpath.c

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sys/netinet/tcp_stacks/fastpath.c

Show First 20 Lines • Show All 925 Lines • ▼ Show 20 Lines if (tp->t_flags & TF_NEEDFIN) {
cc_conn_init(tp); cc_conn_init(tp);
tcp_timer_activate(tp, TT_KEEP, TP_KEEPIDLE(tp)); tcp_timer_activate(tp, TT_KEEP, TP_KEEPIDLE(tp));
} }
/* /*
* If segment contains data or ACK, will call tcp_reass() * If segment contains data or ACK, will call tcp_reass()
* later; if not, do so now to pass queued data to user. * later; if not, do so now to pass queued data to user.
*/ */
if (tlen == 0 && (thflags & TH_FIN) == 0) if (tlen == 0 && (thflags & TH_FIN) == 0)
(void) tcp_reass(tp, (struct tcphdr *)0, 0, (void) tcp_reass(tp, (struct tcphdr *)0, NULL, 0,
(struct mbuf *)0); (struct mbuf *)0);
tp->snd_wl1 = th->th_seq - 1; tp->snd_wl1 = th->th_seq - 1;
/* FALLTHROUGH */ /* FALLTHROUGH */
/* /*
* In ESTABLISHED state: drop duplicate ACKs; ACK out of range * In ESTABLISHED state: drop duplicate ACKs; ACK out of range
* ACKs. If the ack is in the range * ACKs. If the ack is in the range
* tp->snd_una < th->th_ack <= tp->snd_max * tp->snd_una < th->th_ack <= tp->snd_max
▲ Show 20 Lines • Show All 516 Lines • ▼ Show 20 Lines if ((tlen || (thflags & TH_FIN)) &&
* connection, and the queue is empty), avoiding linkage into * connection, and the queue is empty), avoiding linkage into
* and removal from the queue and repetition of various * and removal from the queue and repetition of various
* conversions. * conversions.
* Set DELACK for segments received in order, but ack * Set DELACK for segments received in order, but ack
* immediately when segments are out of order (so * immediately when segments are out of order (so
* fast retransmit can work). * fast retransmit can work).
*/ */
if (th->th_seq == tp->rcv_nxt && if (th->th_seq == tp->rcv_nxt &&
LIST_EMPTY(&tp->t_segq) && SEGQ_EMPTY(tp) &&
TCPS_HAVEESTABLISHED(tp->t_state)) { TCPS_HAVEESTABLISHED(tp->t_state)) {
if (DELAY_ACK(tp, tlen)) if (DELAY_ACK(tp, tlen))
tp->t_flags |= TF_DELACK; tp->t_flags |= TF_DELACK;
else else
tp->t_flags |= TF_ACKNOW; tp->t_flags |= TF_ACKNOW;
tp->rcv_nxt += tlen; tp->rcv_nxt += tlen;
thflags = th->th_flags & TH_FIN; thflags = th->th_flags & TH_FIN;
TCPSTAT_INC(tcps_rcvpack); TCPSTAT_INC(tcps_rcvpack);
TCPSTAT_ADD(tcps_rcvbyte, tlen); TCPSTAT_ADD(tcps_rcvbyte, tlen);
SOCKBUF_LOCK(&so->so_rcv); SOCKBUF_LOCK(&so->so_rcv);
if (so->so_rcv.sb_state & SBS_CANTRCVMORE) if (so->so_rcv.sb_state & SBS_CANTRCVMORE)
m_freem(m); m_freem(m);
else else
sbappendstream_locked(&so->so_rcv, m, 0); sbappendstream_locked(&so->so_rcv, m, 0);
/* NB: sorwakeup_locked() does an implicit unlock. */ /* NB: sorwakeup_locked() does an implicit unlock. */
sorwakeup_locked(so); sorwakeup_locked(so);
} else { } else {
/* /*
* XXX: Due to the header drop above "th" is * XXX: Due to the header drop above "th" is
* theoretically invalid by now. Fortunately * theoretically invalid by now. Fortunately
* m_adj() doesn't actually frees any mbufs * m_adj() doesn't actually frees any mbufs
* when trimming from the head. * when trimming from the head.
*/ */
thflags = tcp_reass(tp, th, &tlen, m); thflags = tcp_reass(tp, th, &save_start, &tlen, m);
tp->t_flags |= TF_ACKNOW; tp->t_flags |= TF_ACKNOW;
} }
if (tlen > 0 && (tp->t_flags & TF_SACK_PERMIT)) if (tlen > 0 && (tp->t_flags & TF_SACK_PERMIT))
tcp_update_sack_list(tp, save_start, save_start + tlen); tcp_update_sack_list(tp, save_start, save_start + tlen);
#if 0 #if 0
/* /*
* Note the amount of data that peer has sent into * Note the amount of data that peer has sent into
* our window, in order to estimate the sender's * our window, in order to estimate the sender's
▲ Show 20 Lines • Show All 400 Lines • ▼ Show 20 Lines#endif
* be TH_NEEDSYN. * be TH_NEEDSYN.
*/ */
if (__predict_true(tp->t_state == TCPS_ESTABLISHED && if (__predict_true(tp->t_state == TCPS_ESTABLISHED &&
th->th_seq == tp->rcv_nxt && th->th_seq == tp->rcv_nxt &&
(thflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) == TH_ACK && (thflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) == TH_ACK &&
tp->snd_nxt == tp->snd_max && tp->snd_nxt == tp->snd_max &&
can_enter && can_enter &&
((tp->t_flags & (TF_NEEDSYN|TF_NEEDFIN)) == 0) && ((tp->t_flags & (TF_NEEDSYN|TF_NEEDFIN)) == 0) &&
LIST_EMPTY(&tp->t_segq) && SEGQ_EMPTY(tp) &&
((to.to_flags & TOF_TS) == 0 || ((to.to_flags & TOF_TS) == 0 ||
TSTMP_GEQ(to.to_tsval, tp->ts_recent)))) { TSTMP_GEQ(to.to_tsval, tp->ts_recent)))) {
if (__predict_true((tlen == 0) && if (__predict_true((tlen == 0) &&
(SEQ_LEQ(th->th_ack, tp->snd_max) && (SEQ_LEQ(th->th_ack, tp->snd_max) &&
!IN_RECOVERY(tp->t_flags) && !IN_RECOVERY(tp->t_flags) &&
(to.to_flags & TOF_SACK) == 0 && (to.to_flags & TOF_SACK) == 0 &&
TAILQ_EMPTY(&tp->snd_holes)))) { TAILQ_EMPTY(&tp->snd_holes)))) {
/* We are done */ /* We are done */
▲ Show 20 Lines • Show All 435 Lines • ▼ Show 20 Lines#endif
* Make sure that the hidden state-flags are also off. * Make sure that the hidden state-flags are also off.
* Since we check for TCPS_ESTABLISHED first, it can only * Since we check for TCPS_ESTABLISHED first, it can only
* be TH_NEEDSYN. * be TH_NEEDSYN.
*/ */
if (__predict_true(tp->t_state == TCPS_ESTABLISHED) && if (__predict_true(tp->t_state == TCPS_ESTABLISHED) &&
__predict_true(((to.to_flags & TOF_SACK) == 0)) && __predict_true(((to.to_flags & TOF_SACK) == 0)) &&
__predict_true(tlen == 0) && __predict_true(tlen == 0) &&
__predict_true((thflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) == TH_ACK) && __predict_true((thflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) == TH_ACK) &&
__predict_true(LIST_EMPTY(&tp->t_segq)) && __predict_true(SEGQ_EMPTY(tp)) &&
__predict_true(th->th_seq == tp->rcv_nxt)) { __predict_true(th->th_seq == tp->rcv_nxt)) {
if (tcp_fastack(m, th, so, tp, &to, drop_hdrlen, tlen, if (tcp_fastack(m, th, so, tp, &to, drop_hdrlen, tlen,
ti_locked, tiwin)) { ti_locked, tiwin)) {
return; return;
} }
} }
tcp_do_slowpath(m, th, so, tp, &to, drop_hdrlen, tlen, tcp_do_slowpath(m, th, so, tp, &to, drop_hdrlen, tlen,
ti_locked, tiwin, thflags); ti_locked, tiwin, thflags);
▲ Show 20 Lines • Show All 63 Lines • Show Last 20 Lines