tcp: fix ssthresh and undo for consecutive short FRTO episodes

[firefly-linux-kernel-4.4.55.git] / net / ipv4 / tcp_input.c

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 4f6cfbc577753c7bef689c07b80991d41a467537..a906e0200ff26144727a1c6c90718cf1fa492dde 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2687,7 +2687,6 @@ static void tcp_enter_recovery(struct sock *sk, bool ece_ack)
  */
 static void tcp_process_loss(struct sock *sk, int flag, bool is_dupack)
 {
-       struct inet_connection_sock *icsk = inet_csk(sk);
        struct tcp_sock *tp = tcp_sk(sk);
        bool recovered = !before(tp->snd_una, tp->high_seq);
 
@@ -2713,12 +2712,9 @@ static void tcp_process_loss(struct sock *sk, int flag, bool is_dupack)
 
        if (recovered) {
                /* F-RTO RFC5682 sec 3.1 step 2.a and 1st part of step 3.a */
-               icsk->icsk_retransmits = 0;
                tcp_try_undo_recovery(sk);
                return;
        }
-       if (flag & FLAG_DATA_ACKED)
-               icsk->icsk_retransmits = 0;
        if (tcp_is_reno(tp)) {
                /* A Reno DUPACK means new data in F-RTO step 2.b above are
                 * delivered. Lower inflight to clock out (re)tranmissions.
@@ -3405,8 +3401,10 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
            icsk->icsk_pending == ICSK_TIME_LOSS_PROBE)
                tcp_rearm_rto(sk);
 
-       if (after(ack, prior_snd_una))
+       if (after(ack, prior_snd_una)) {
                flag |= FLAG_SND_UNA_ADVANCED;
+               icsk->icsk_retransmits = 0;
+       }
 
        prior_fackets = tp->fackets_out;