diff options
| -rw-r--r-- | include/net/tcp.h | 2 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 24 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 3 |
3 files changed, 23 insertions, 6 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index 7de4ea3a04d..4fd3eb2f8ec 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -752,6 +752,8 @@ static inline unsigned int tcp_packets_in_flight(const struct tcp_sock *tp) return tp->packets_out - tcp_left_out(tp) + tp->retrans_out; } +extern int tcp_limit_reno_sacked(struct tcp_sock *tp); + /* If cwnd > ssthresh, we may raise ssthresh to be half-way to cwnd. * The exception is rate halving phase, when cwnd is decreasing towards * ssthresh. diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 7d0958785bf..b4812c3cbbc 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1625,13 +1625,11 @@ out: return flag; } -/* If we receive more dupacks than we expected counting segments - * in assumption of absent reordering, interpret this as reordering. - * The only another reason could be bug in receiver TCP. +/* Limits sacked_out so that sum with lost_out isn't ever larger than + * packets_out. Returns zero if sacked_out adjustement wasn't necessary. */ -static void tcp_check_reno_reordering(struct sock *sk, const int addend) +int tcp_limit_reno_sacked(struct tcp_sock *tp) { - struct tcp_sock *tp = tcp_sk(sk); u32 holes; holes = max(tp->lost_out, 1U); @@ -1639,8 +1637,20 @@ static void tcp_check_reno_reordering(struct sock *sk, const int addend) if ((tp->sacked_out + holes) > tp->packets_out) { tp->sacked_out = tp->packets_out - holes; - tcp_update_reordering(sk, tp->packets_out + addend, 0); + return 1; } + return 0; +} + +/* If we receive more dupacks than we expected counting segments + * in assumption of absent reordering, interpret this as reordering. + * The only another reason could be bug in receiver TCP. + */ +static void tcp_check_reno_reordering(struct sock *sk, const int addend) +{ + struct tcp_sock *tp = tcp_sk(sk); + if (tcp_limit_reno_sacked(tp)) + tcp_update_reordering(sk, tp->packets_out + addend, 0); } /* Emulate SACKs for SACKless connection: account for a new dupack. */ @@ -2600,6 +2610,8 @@ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked, int flag) case TCP_CA_Loss: if (flag & FLAG_DATA_ACKED) icsk->icsk_retransmits = 0; + if (tcp_is_reno(tp) && flag & FLAG_SND_UNA_ADVANCED) + tcp_reset_reno_sack(tp); if (!tcp_try_undo_loss(sk)) { tcp_moderate_cwnd(tp); tcp_xmit_retransmit_queue(sk); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 72b9350006f..d29ef79c00c 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1808,6 +1808,9 @@ void tcp_simple_retransmit(struct sock *sk) if (!lost) return; + if (tcp_is_reno(tp)) + tcp_limit_reno_sacked(tp); + tcp_verify_left_out(tp); /* Don't muck with the congestion window here. |