diff options
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 65 |
1 files changed, 56 insertions, 9 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 8afb0950a697..ab87f0285b72 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -778,6 +778,16 @@ new_measure: tp->rcvq_space.time = tp->tcp_mstamp; } +static void tcp_save_lrcv_flowlabel(struct sock *sk, const struct sk_buff *skb) +{ +#if IS_ENABLED(CONFIG_IPV6) + struct inet_connection_sock *icsk = inet_csk(sk); + + if (skb->protocol == htons(ETH_P_IPV6)) + icsk->icsk_ack.lrcv_flowlabel = ntohl(ip6_flowlabel(ipv6_hdr(skb))); +#endif +} + /* There is something which you must keep in mind when you analyze the * behavior of the tp->ato delayed ack timeout interval. When a * connection starts up, we want to ack as quickly as possible. The @@ -826,6 +836,7 @@ static void tcp_event_data_recv(struct sock *sk, struct sk_buff *skb) } } icsk->icsk_ack.lrcvtime = now; + tcp_save_lrcv_flowlabel(sk, skb); tcp_ecn_check_ce(sk, skb); @@ -940,8 +951,8 @@ static void tcp_update_pacing_rate(struct sock *sk) * without any lock. We want to make sure compiler wont store * intermediate values in this location. */ - WRITE_ONCE(sk->sk_pacing_rate, min_t(u64, rate, - sk->sk_max_pacing_rate)); + WRITE_ONCE(sk->sk_pacing_rate, + min_t(u64, rate, READ_ONCE(sk->sk_max_pacing_rate))); } /* Calculate rto without backoff. This is the second half of Van Jacobson's @@ -2101,6 +2112,10 @@ void tcp_clear_retrans(struct tcp_sock *tp) tp->undo_marker = 0; tp->undo_retrans = -1; tp->sacked_out = 0; + tp->rto_stamp = 0; + tp->total_rto = 0; + tp->total_rto_recoveries = 0; + tp->total_rto_time = 0; } static inline void tcp_init_undo(struct tcp_sock *tp) @@ -2838,6 +2853,14 @@ void tcp_enter_recovery(struct sock *sk, bool ece_ack) tcp_set_ca_state(sk, TCP_CA_Recovery); } +static void tcp_update_rto_time(struct tcp_sock *tp) +{ + if (tp->rto_stamp) { + tp->total_rto_time += tcp_time_stamp(tp) - tp->rto_stamp; + tp->rto_stamp = 0; + } +} + /* Process an ACK in CA_Loss state. Move to CA_Open if lost data are * recovered or spurious. Otherwise retransmits more on partial ACKs. */ @@ -3042,6 +3065,8 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, break; case TCP_CA_Loss: tcp_process_loss(sk, flag, num_dupack, rexmit); + if (icsk->icsk_ca_state != TCP_CA_Loss) + tcp_update_rto_time(tp); tcp_identify_packet_loss(sk, ack_flag); if (!(icsk->icsk_ca_state == TCP_CA_Open || (*ack_flag & FLAG_LOST_RETRANS))) @@ -4499,12 +4524,23 @@ static void tcp_rcv_spurious_retrans(struct sock *sk, const struct sk_buff *skb) { /* When the ACK path fails or drops most ACKs, the sender would * timeout and spuriously retransmit the same segment repeatedly. - * The receiver remembers and reflects via DSACKs. Leverage the - * DSACK state and change the txhash to re-route speculatively. + * If it seems our ACKs are not reaching the other side, + * based on receiving a duplicate data segment with new flowlabel + * (suggesting the sender suffered an RTO), and we are not already + * repathing due to our own RTO, then rehash the socket to repath our + * packets. */ - if (TCP_SKB_CB(skb)->seq == tcp_sk(sk)->duplicate_sack[0].start_seq && +#if IS_ENABLED(CONFIG_IPV6) + if (inet_csk(sk)->icsk_ca_state != TCP_CA_Loss && + skb->protocol == htons(ETH_P_IPV6) && + (tcp_sk(sk)->inet_conn.icsk_ack.lrcv_flowlabel != + ntohl(ip6_flowlabel(ipv6_hdr(skb)))) && sk_rethink_txhash(sk)) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDUPLICATEDATAREHASH); + + /* Save last flowlabel after a spurious retrans. */ + tcp_save_lrcv_flowlabel(sk, skb); +#endif } static void tcp_send_dupack(struct sock *sk, const struct sk_buff *skb) @@ -4821,6 +4857,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) u32 seq, end_seq; bool fragstolen; + tcp_save_lrcv_flowlabel(sk, skb); tcp_ecn_check_ce(sk, skb); if (unlikely(tcp_try_rmem_schedule(sk, skb, skb->truesize))) { @@ -5566,6 +5603,14 @@ static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible) tcp_in_quickack_mode(sk) || /* Protocol state mandates a one-time immediate ACK */ inet_csk(sk)->icsk_ack.pending & ICSK_ACK_NOW) { + /* If we are running from __release_sock() in user context, + * Defer the ack until tcp_release_cb(). + */ + if (sock_owned_by_user_nocheck(sk) && + READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_backlog_ack_defer)) { + set_bit(TCP_ACK_DEFERRED, &sk->sk_tsq_flags); + return; + } send_now: tcp_send_ack(sk); return; @@ -6449,22 +6494,24 @@ reset_and_undo: static void tcp_rcv_synrecv_state_fastopen(struct sock *sk) { + struct tcp_sock *tp = tcp_sk(sk); struct request_sock *req; /* If we are still handling the SYNACK RTO, see if timestamp ECR allows * undo. If peer SACKs triggered fast recovery, we can't undo here. */ - if (inet_csk(sk)->icsk_ca_state == TCP_CA_Loss) - tcp_try_undo_loss(sk, false); + if (inet_csk(sk)->icsk_ca_state == TCP_CA_Loss && !tp->packets_out) + tcp_try_undo_recovery(sk); /* Reset rtx states to prevent spurious retransmits_timed_out() */ - tcp_sk(sk)->retrans_stamp = 0; + tcp_update_rto_time(tp); + tp->retrans_stamp = 0; inet_csk(sk)->icsk_retransmits = 0; /* Once we leave TCP_SYN_RECV or TCP_FIN_WAIT_1, * we no longer need req so release it. */ - req = rcu_dereference_protected(tcp_sk(sk)->fastopen_rsk, + req = rcu_dereference_protected(tp->fastopen_rsk, lockdep_sock_is_held(sk)); reqsk_fastopen_remove(sk, req, false); |