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Index: sys/netinet/tcp_stacks/rack.c
===================================================================
--- sys/netinet/tcp_stacks/rack.c
+++ sys/netinet/tcp_stacks/rack.c
@@ -6567,9 +6567,86 @@
rack_cc_conn_init(struct tcpcb *tp)
{
struct tcp_rack *rack;
+ struct hc_metrics_lite metrics;
+ u_int maxseg;
+ int rtt;
rack = (struct tcp_rack *)tp->t_fb_ptr;
- cc_conn_init(tp);
+
+ maxseg = tcp_maxseg(tp);
+ if (tp->t_srtt == 0 && (rtt = metrics.rmx_rtt)) {
+ /* First pull it out of the HC */
+ tp->t_srtt = rtt;
+ tp->t_rttbest = tp->t_srtt + TCP_RTT_SCALE;
+ TCPSTAT_INC(tcps_usedrtt);
+ if (metrics.rmx_rttvar) {
+ tp->t_rttvar = metrics.rmx_rttvar;
+ TCPSTAT_INC(tcps_usedrttvar);
+ } else {
+ /* default variation is +- 1 rtt */
+ tp->t_rttvar =
+ tp->t_srtt * TCP_RTTVAR_SCALE / TCP_RTT_SCALE;
+ }
+ /*
+ * Now convert to rack's internal format.
+ */
+ if (tp->t_srtt > 1) {
+ uint32_t val, frac;
+
+ val = tp->t_srtt >> TCP_RTT_SHIFT;
+ frac = tp->t_srtt & 0x1f;
+ tp->t_srtt = TICKS_2_USEC(val);
+ /*
+ * frac is the fractional part of the srtt (if any)
+ * but its in ticks and every bit represents
+ * 1/32nd of a hz.
+ */
+ if (frac) {
+ if (hz == 1000) {
+ frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE);
+ } else {
+ frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE));
+ }
+ tp->t_srtt += frac;
+ }
+ }
+ if (tp->t_rttvar) {
+ uint32_t val, frac;
+
+ val = tp->t_rttvar >> TCP_RTTVAR_SHIFT;
+ frac = tp->t_rttvar & 0x1f;
+ tp->t_rttvar = TICKS_2_USEC(val);
+ /*
+ * frac is the fractional part of the srtt (if any)
+ * but its in ticks and every bit represents
+ * 1/32nd of a hz.
+ */
+ if (frac) {
+ if (hz == 1000) {
+ frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE);
+ } else {
+ frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE));
+ }
+ tp->t_rttvar += frac;
+ }
+ }
+ RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp),
+ rack_rto_min, rack_rto_max);
+ }
+ /*
+ * Set the initial slow-start flight size.
+ *
+ * If a SYN or SYN/ACK was lost and retransmitted, we have to
+ * reduce the initial CWND to one segment as congestion is likely
+ * requiring us to be cautious.
+ */
+ if (tp->snd_cwnd == 1)
+ tp->snd_cwnd = maxseg; /* SYN(-ACK) lost */
+ else
+ tp->snd_cwnd = tcp_compute_initwnd(maxseg);
+
+ if (CC_ALGO(tp)->conn_init != NULL)
+ CC_ALGO(tp)->conn_init(tp->ccv);
/*
* We want a chance to stay in slowstart as
* we create a connection. TCP spec says that
@@ -12187,7 +12264,8 @@
tp->t_rttvar += frac;
}
}
- tp->t_rxtcur = TICKS_2_USEC(tp->t_rxtcur);
+ RACK_TCPT_RANGESET(tp->t_rxtcur, RACK_REXMTVAL(tp),
+ rack_rto_min, rack_rto_max);
tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow);
if (rack_def_profile)
rack_set_profile(rack, rack_def_profile);
@@ -12230,7 +12308,7 @@
rack_stop_all_timers(tp);
/* Lets setup the fsb block */
rack_start_hpts_timer(rack, tp, tcp_get_usecs(NULL), 0, 0, 0);
- rack_log_rtt_shrinks(rack, us_cts, 0,
+ rack_log_rtt_shrinks(rack, us_cts, tp->t_rxtcur,
__LINE__, RACK_RTTS_INIT);
return (0);
}
Index: sys/netinet/tcp_subr.c
===================================================================
--- sys/netinet/tcp_subr.c
+++ sys/netinet/tcp_subr.c
@@ -2309,62 +2309,6 @@
tp->t_fb->tfb_tcp_timer_stop_all(tp);
}
- /*
- * If we got enough samples through the srtt filter,
- * save the rtt and rttvar in the routing entry.
- * 'Enough' is arbitrarily defined as 4 rtt samples.
- * 4 samples is enough for the srtt filter to converge
- * to within enough % of the correct value; fewer samples
- * and we could save a bogus rtt. The danger is not high
- * as tcp quickly recovers from everything.
- * XXX: Works very well but needs some more statistics!
- */
- if (tp->t_rttupdated >= 4) {
- struct hc_metrics_lite metrics;
- uint32_t ssthresh;
-
- bzero(&metrics, sizeof(metrics));
- /*
- * Update the ssthresh always when the conditions below
- * are satisfied. This gives us better new start value
- * for the congestion avoidance for new connections.
- * ssthresh is only set if packet loss occurred on a session.
- *
- * XXXRW: 'so' may be NULL here, and/or socket buffer may be
- * being torn down. Ideally this code would not use 'so'.
- */
- ssthresh = tp->snd_ssthresh;
- if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) {
- /*
- * convert the limit from user data bytes to
- * packets then to packet data bytes.
- */
- ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg;
- if (ssthresh < 2)
- ssthresh = 2;
- ssthresh *= (tp->t_maxseg +
-#ifdef INET6
- (isipv6 ? sizeof (struct ip6_hdr) +
- sizeof (struct tcphdr) :
-#endif
- sizeof (struct tcpiphdr)
-#ifdef INET6
- )
-#endif
- );
- } else
- ssthresh = 0;
- metrics.rmx_ssthresh = ssthresh;
-
- metrics.rmx_rtt = tp->t_srtt;
- metrics.rmx_rttvar = tp->t_rttvar;
- metrics.rmx_cwnd = tp->snd_cwnd;
- metrics.rmx_sendpipe = 0;
- metrics.rmx_recvpipe = 0;
-
- tcp_hc_update(&inp->inp_inc, &metrics);
- }
-
/* free the reassembly queue, if any */
tcp_reass_flush(tp);
@@ -2404,6 +2348,68 @@
TCPSTATES_DEC(tp->t_state);
if (tp->t_fb->tfb_tcp_fb_fini)
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
+
+ /*
+ * If we got enough samples through the srtt filter,
+ * save the rtt and rttvar in the routing entry.
+ * 'Enough' is arbitrarily defined as 4 rtt samples.
+ * 4 samples is enough for the srtt filter to converge
+ * to within enough % of the correct value; fewer samples
+ * and we could save a bogus rtt. The danger is not high
+ * as tcp quickly recovers from everything.
+ * XXX: Works very well but needs some more statistics!
+ *
+ * XXXRRS: Updating must be after the stack fini() since
+ * that may be converting some internal representation of
+ * say srtt etc into the general one used by other stacks.
+ * Lets also at least protect against the so being NULL
+ * as RW stated below.
+ */
+ if ((tp->t_rttupdated >= 4) && (so != NULL)) {
+ struct hc_metrics_lite metrics;
+ uint32_t ssthresh;
+
+ bzero(&metrics, sizeof(metrics));
+ /*
+ * Update the ssthresh always when the conditions below
+ * are satisfied. This gives us better new start value
+ * for the congestion avoidance for new connections.
+ * ssthresh is only set if packet loss occurred on a session.
+ *
+ * XXXRW: 'so' may be NULL here, and/or socket buffer may be
+ * being torn down. Ideally this code would not use 'so'.
+ */
+ ssthresh = tp->snd_ssthresh;
+ if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) {
+ /*
+ * convert the limit from user data bytes to
+ * packets then to packet data bytes.
+ */
+ ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg;
+ if (ssthresh < 2)
+ ssthresh = 2;
+ ssthresh *= (tp->t_maxseg +
+#ifdef INET6
+ (isipv6 ? sizeof (struct ip6_hdr) +
+ sizeof (struct tcphdr) :
+#endif
+ sizeof (struct tcpiphdr)
+#ifdef INET6
+ )
+#endif
+ );
+ } else
+ ssthresh = 0;
+ metrics.rmx_ssthresh = ssthresh;
+
+ metrics.rmx_rtt = tp->t_srtt;
+ metrics.rmx_rttvar = tp->t_rttvar;
+ metrics.rmx_cwnd = tp->snd_cwnd;
+ metrics.rmx_sendpipe = 0;
+ metrics.rmx_recvpipe = 0;
+
+ tcp_hc_update(&inp->inp_inc, &metrics);
+ }
refcount_release(&tp->t_fb->tfb_refcnt);
tp->t_inpcb = NULL;
uma_zfree(V_tcpcb_zone, tp);

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