diff options
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 57 |
1 files changed, 53 insertions, 4 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index b565c8a8e7ba..fb053942dba2 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2108,6 +2108,10 @@ 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) @@ -2452,8 +2456,22 @@ static bool tcp_skb_spurious_retrans(const struct tcp_sock *tp, */ static inline bool tcp_packet_delayed(const struct tcp_sock *tp) { - return tp->retrans_stamp && - tcp_tsopt_ecr_before(tp, tp->retrans_stamp); + const struct sock *sk = (const struct sock *)tp; + + if (tp->retrans_stamp && + tcp_tsopt_ecr_before(tp, tp->retrans_stamp)) + return true; /* got echoed TS before first retransmission */ + + /* Check if nothing was retransmitted (retrans_stamp==0), which may + * happen in fast recovery due to TSQ. But we ignore zero retrans_stamp + * in TCP_SYN_SENT, since when we set FLAG_SYN_ACKED we also clear + * retrans_stamp even if we had retransmitted the SYN. + */ + if (!tp->retrans_stamp && /* no record of a retransmit/SYN? */ + sk->sk_state != TCP_SYN_SENT) /* not the FLAG_SYN_ACKED case? */ + return true; /* nothing was retransmitted */ + + return false; } /* Undo procedures. */ @@ -2487,6 +2505,16 @@ static bool tcp_any_retrans_done(const struct sock *sk) return false; } +/* If loss recovery is finished and there are no retransmits out in the + * network, then we clear retrans_stamp so that upon the next loss recovery + * retransmits_timed_out() and timestamp-undo are using the correct value. + */ +static void tcp_retrans_stamp_cleanup(struct sock *sk) +{ + if (!tcp_any_retrans_done(sk)) + tcp_sk(sk)->retrans_stamp = 0; +} + static void DBGUNDO(struct sock *sk, const char *msg) { #if FASTRETRANS_DEBUG > 1 @@ -2854,6 +2882,9 @@ void tcp_enter_recovery(struct sock *sk, bool ece_ack) struct tcp_sock *tp = tcp_sk(sk); int mib_idx; + /* Start the clock with our fast retransmit, for undo and ETIMEDOUT. */ + tcp_retrans_stamp_cleanup(sk); + if (tcp_is_reno(tp)) mib_idx = LINUX_MIB_TCPRENORECOVERY; else @@ -2872,6 +2903,14 @@ 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. */ @@ -3076,6 +3115,8 @@ 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))) @@ -6513,9 +6554,17 @@ static void tcp_rcv_synrecv_state_fastopen(struct sock *sk) 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() */ - tp->retrans_stamp = 0; + tcp_update_rto_time(tp); inet_csk(sk)->icsk_retransmits = 0; + /* In tcp_fastopen_synack_timer() on the first SYNACK RTO we set + * retrans_stamp but don't enter CA_Loss, so in case that happened we + * need to zero retrans_stamp here to prevent spurious + * retransmits_timed_out(). However, if the ACK of our SYNACK caused us + * to enter CA_Recovery then we need to leave retrans_stamp as it was + * set entering CA_Recovery, for correct retransmits_timed_out() and + * undo behavior. + */ + tcp_retrans_stamp_cleanup(sk); /* Once we leave TCP_SYN_RECV or TCP_FIN_WAIT_1, * we no longer need req so release it. |