diff options
-rw-r--r-- | net/ipv4/tcp_input.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 4b255fe999d..41163ddc312 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1851,19 +1851,22 @@ static inline u32 tcp_cwnd_min(const struct sock *sk) } /* Decrease cwnd each second ack. */ -static void tcp_cwnd_down(struct sock *sk) +static void tcp_cwnd_down(struct sock *sk, int flag) { struct tcp_sock *tp = tcp_sk(sk); int decr = tp->snd_cwnd_cnt + 1; - tp->snd_cwnd_cnt = decr&1; - decr >>= 1; + if ((flag&FLAG_FORWARD_PROGRESS) || + (IsReno(tp) && !(flag&FLAG_NOT_DUP))) { + tp->snd_cwnd_cnt = decr&1; + decr >>= 1; - if (decr && tp->snd_cwnd > tcp_cwnd_min(sk)) - tp->snd_cwnd -= decr; + if (decr && tp->snd_cwnd > tcp_cwnd_min(sk)) + tp->snd_cwnd -= decr; - tp->snd_cwnd = min(tp->snd_cwnd, tcp_packets_in_flight(tp)+1); - tp->snd_cwnd_stamp = tcp_time_stamp; + tp->snd_cwnd = min(tp->snd_cwnd, tcp_packets_in_flight(tp)+1); + tp->snd_cwnd_stamp = tcp_time_stamp; + } } /* Nothing was retransmitted or returned timestamp is less @@ -2060,7 +2063,7 @@ static void tcp_try_to_open(struct sock *sk, int flag) } tcp_moderate_cwnd(tp); } else { - tcp_cwnd_down(sk); + tcp_cwnd_down(sk, flag); } } @@ -2260,7 +2263,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una, if (is_dupack || tcp_head_timedout(sk)) tcp_update_scoreboard(sk); - tcp_cwnd_down(sk); + tcp_cwnd_down(sk, flag); tcp_xmit_retransmit_queue(sk); } |