diff options
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 19 | ||||
| -rw-r--r-- | include/linux/tcp.h | 3 | ||||
| -rw-r--r-- | include/net/tcp.h | 19 | ||||
| -rw-r--r-- | net/ipv4/inet_diag.c | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp.c | 3 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 60 | ||||
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp_metrics.c | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp_minisocks.c | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 11 | ||||
| -rw-r--r-- | net/ipv4/tcp_timer.c | 3 | ||||
| -rw-r--r-- | net/ipv6/tcp_ipv6.c | 1 |
12 files changed, 12 insertions, 111 deletions
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 7dd65c9cf707..7de2cf79e16f 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -246,21 +246,12 @@ tcp_dsack - BOOLEAN Allows TCP to send "duplicate" SACKs. tcp_early_retrans - INTEGER - Enable Early Retransmit (ER), per RFC 5827. ER lowers the threshold - for triggering fast retransmit when the amount of outstanding data is - small and when no previously unsent data can be transmitted (such - that limited transmit could be used). Also controls the use of - Tail loss probe (TLP) that converts RTOs occurring due to tail - losses into fast recovery (draft-dukkipati-tcpm-tcp-loss-probe-01). + Tail loss probe (TLP) converts RTOs occurring due to tail + losses into fast recovery (draft-ietf-tcpm-rack). Note that + TLP requires RACK to function properly (see tcp_recovery below) Possible values: - 0 disables ER - 1 enables ER - 2 enables ER but delays fast recovery and fast retransmit - by a fourth of RTT. This mitigates connection falsely - recovers when network has a small degree of reordering - (less than 3 packets). - 3 enables delayed ER and TLP. - 4 enables TLP only. + 0 disables TLP + 3 or 4 enables TLP Default: 3 tcp_ecn - INTEGER diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 8e5f4c15d0e5..4733368f953a 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -224,8 +224,7 @@ struct tcp_sock { repair : 1, frto : 1;/* F-RTO (RFC5682) activated in CA_Loss */ u8 repair_queue; - u8 do_early_retrans:1,/* Enable RFC5827 early-retransmit */ - syn_data:1, /* SYN includes data */ + u8 syn_data:1, /* SYN includes data */ syn_fastopen:1, /* SYN includes Fast Open option */ syn_fastopen_exp:1,/* SYN includes Fast Open exp. option */ syn_data_acked:1,/* data in SYN is acked by SYN-ACK */ diff --git a/include/net/tcp.h b/include/net/tcp.h index 423438dd6fe9..c55d65f74f7f 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -565,7 +565,6 @@ void tcp_skb_collapse_tstamp(struct sk_buff *skb, const struct sk_buff *next_skb); /* tcp_input.c */ -void tcp_resume_early_retransmit(struct sock *sk); void tcp_rearm_rto(struct sock *sk); void tcp_synack_rtt_meas(struct sock *sk, struct request_sock *req); void tcp_reset(struct sock *sk); @@ -1037,24 +1036,6 @@ static inline void tcp_enable_fack(struct tcp_sock *tp) tp->rx_opt.sack_ok |= TCP_FACK_ENABLED; } -/* TCP early-retransmit (ER) is similar to but more conservative than - * the thin-dupack feature. Enable ER only if thin-dupack is disabled. - */ -static inline void tcp_enable_early_retrans(struct tcp_sock *tp) -{ - struct net *net = sock_net((struct sock *)tp); - - tp->do_early_retrans = sysctl_tcp_early_retrans && - sysctl_tcp_early_retrans < 4 && !sysctl_tcp_thin_dupack && - !(sysctl_tcp_recovery & TCP_RACK_LOSS_DETECTION) && - net->ipv4.sysctl_tcp_reordering == 3; -} - -static inline void tcp_disable_early_retrans(struct tcp_sock *tp) -{ - tp->do_early_retrans = 0; -} - static inline unsigned int tcp_left_out(const struct tcp_sock *tp) { return tp->sacked_out + tp->lost_out; diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index d216e40623d3..3828b3a805cd 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -215,7 +215,6 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, } if (icsk->icsk_pending == ICSK_TIME_RETRANS || - icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { r->idiag_timer = 1; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index c8d46c140b4a..d9023e8ed53e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -406,7 +406,6 @@ void tcp_init_sock(struct sock *sk) tp->mss_cache = TCP_MSS_DEFAULT; tp->reordering = sock_net(sk)->ipv4.sysctl_tcp_reordering; - tcp_enable_early_retrans(tp); tcp_assign_congestion_control(sk); tp->tsoffset = 0; @@ -2477,8 +2476,6 @@ static int do_tcp_setsockopt(struct sock *sk, int level, err = -EINVAL; else { tp->thin_dupack = val; - if (tp->thin_dupack) - tcp_disable_early_retrans(tp); } break; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a041a92348ee..79c819077a59 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -904,8 +904,6 @@ static void tcp_update_reordering(struct sock *sk, const int metric, tcp_disable_fack(tp); } - if (metric > 0) - tcp_disable_early_retrans(tp); tp->rack.reord = 1; } @@ -2054,30 +2052,6 @@ static inline int tcp_dupack_heuristics(const struct tcp_sock *tp) return tcp_is_fack(tp) ? tp->fackets_out : tp->sacked_out + 1; } -static bool tcp_pause_early_retransmit(struct sock *sk, int flag) -{ - struct tcp_sock *tp = tcp_sk(sk); - unsigned long delay; - - /* Delay early retransmit and entering fast recovery for - * max(RTT/4, 2msec) unless ack has ECE mark, no RTT samples - * available, or RTO is scheduled to fire first. - */ - if (sysctl_tcp_early_retrans < 2 || sysctl_tcp_early_retrans > 3 || - (flag & FLAG_ECE) || !tp->srtt_us) - return false; - - delay = max(usecs_to_jiffies(tp->srtt_us >> 5), - msecs_to_jiffies(2)); - - if (!time_after(inet_csk(sk)->icsk_timeout, (jiffies + delay))) - return false; - - inet_csk_reset_xmit_timer(sk, ICSK_TIME_EARLY_RETRANS, delay, - TCP_RTO_MAX); - return true; -} - /* Linux NewReno/SACK/FACK/ECN state machine. * -------------------------------------- * @@ -2221,16 +2195,6 @@ static bool tcp_time_to_recover(struct sock *sk, int flag) tcp_is_sack(tp) && !tcp_send_head(sk)) return true; - /* Trick#6: TCP early retransmit, per RFC5827. To avoid spurious - * retransmissions due to small network reorderings, we implement - * Mitigation A.3 in the RFC and delay the retransmission for a short - * interval if appropriate. - */ - if (tp->do_early_retrans && !tp->retrans_out && tp->sacked_out && - (tp->packets_out >= (tp->sacked_out + 1) && tp->packets_out < 4) && - !tcp_may_send_now(sk)) - return !tcp_pause_early_retransmit(sk, flag); - return false; } @@ -3050,8 +3014,7 @@ void tcp_rearm_rto(struct sock *sk) } else { u32 rto = inet_csk(sk)->icsk_rto; /* Offset the time elapsed after installing regular RTO */ - if (icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || - icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || + if (icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { struct sk_buff *skb = tcp_write_queue_head(sk); const u32 rto_time_stamp = @@ -3068,24 +3031,6 @@ void tcp_rearm_rto(struct sock *sk) } } -/* This function is called when the delayed ER timer fires. TCP enters - * fast recovery and performs fast-retransmit. - */ -void tcp_resume_early_retransmit(struct sock *sk) -{ - struct tcp_sock *tp = tcp_sk(sk); - - tcp_rearm_rto(sk); - - /* Stop if ER is disabled after the delayed ER timer is scheduled */ - if (!tp->do_early_retrans) - return; - - tcp_enter_recovery(sk, false); - tcp_update_scoreboard(sk, 1); - tcp_xmit_retransmit_queue(sk); -} - /* If we get here, the whole TSO packet has not been acked. */ static u32 tcp_tso_acked(struct sock *sk, struct sk_buff *skb) { @@ -3651,8 +3596,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) skb_mstamp_get(&sack_state.ack_time); - if (icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || - icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) + if (icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) tcp_rearm_rto(sk); if (after(ack, prior_snd_una)) { diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index ebf3e0c4967a..63214136cf1c 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2229,7 +2229,6 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) int state; if (icsk->icsk_pending == ICSK_TIME_RETRANS || - icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { timer_active = 1; diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c index ba8f02d0f283..b9ed0d50aead 100644 --- a/net/ipv4/tcp_metrics.c +++ b/net/ipv4/tcp_metrics.c @@ -522,7 +522,6 @@ void tcp_init_metrics(struct sock *sk) val = tcp_metric_get(tm, TCP_METRIC_REORDERING); if (val && tp->reordering != val) { tcp_disable_fack(tp); - tcp_disable_early_retrans(tp); tp->reordering = val; } diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 06fde26a82b7..bdb443471c39 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -468,7 +468,6 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, newtp->sacked_out = 0; newtp->fackets_out = 0; newtp->snd_ssthresh = TCP_INFINITE_SSTHRESH; - tcp_enable_early_retrans(newtp); newtp->tlp_high_seq = 0; newtp->lsndtime = treq->snt_synack.stamp_jiffies; newsk->sk_txhash = treq->txhash; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 6327e4d368a4..9a1a1494b9dd 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -76,10 +76,8 @@ static void tcp_event_new_data_sent(struct sock *sk, const struct sk_buff *skb) tp->snd_nxt = TCP_SKB_CB(skb)->end_seq; tp->packets_out += tcp_skb_pcount(skb); - if (!prior_packets || icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || - icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { + if (!prior_packets || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) tcp_rearm_rto(sk); - } NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPORIGDATASENT, tcp_skb_pcount(skb)); @@ -2289,8 +2287,6 @@ bool tcp_schedule_loss_probe(struct sock *sk) u32 timeout, tlp_time_stamp, rto_time_stamp; u32 rtt = usecs_to_jiffies(tp->srtt_us >> 3); - if (WARN_ON(icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS)) - return false; /* No consecutive loss probes. */ if (WARN_ON(icsk->icsk_pending == ICSK_TIME_LOSS_PROBE)) { tcp_rearm_rto(sk); @@ -2309,8 +2305,9 @@ bool tcp_schedule_loss_probe(struct sock *sk) /* Schedule a loss probe in 2*RTT for SACK capable connections * in Open state, that are either limited by cwnd or application. */ - if (sysctl_tcp_early_retrans < 3 || !tp->packets_out || - !tcp_is_sack(tp) || inet_csk(sk)->icsk_ca_state != TCP_CA_Open) + if ((sysctl_tcp_early_retrans != 3 && sysctl_tcp_early_retrans != 4) || + !tp->packets_out || !tcp_is_sack(tp) || + icsk->icsk_ca_state != TCP_CA_Open) return false; if ((tp->snd_cwnd > tcp_packets_in_flight(tp)) && diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index 953c02a8566e..40d893556e67 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -566,9 +566,6 @@ void tcp_write_timer_handler(struct sock *sk) case ICSK_TIME_REO_TIMEOUT: tcp_rack_reo_timeout(sk); break; - case ICSK_TIME_EARLY_RETRANS: - tcp_resume_early_retransmit(sk); - break; case ICSK_TIME_LOSS_PROBE: tcp_send_loss_probe(sk); break; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f52c3742b404..fc14e04028bf 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1745,7 +1745,6 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) srcp = ntohs(inet->inet_sport); if (icsk->icsk_pending == ICSK_TIME_RETRANS || - icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { timer_active = 1; |