diff options
| author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2007-04-30 11:39:55 +0400 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-30 11:58:12 +0400 |
| commit | 575ee7140dabe9b9c4f66f4f867039b97e548867 (patch) | |
| tree | 035923b29490a85ea7e77c2b0751280f8b7a0ba4 | |
| parent | 157bfc25020f7eb731f94140e099307ade47299e (diff) | |
| download | linux-575ee7140dabe9b9c4f66f4f867039b97e548867.tar.xz | |
[TCP] FRTO: Delay skb available check until it's mandatory
No new data is needed until the first ACK comes, so no need to check
for application limitedness until then.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp_input.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 051f0f815f17..6b669898b197 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1265,20 +1265,15 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ return flag; } -/* F-RTO can only be used if these conditions are satisfied: - * - there must be some unsent new data - * - the advertised window should allow sending it - * - TCP has never retransmitted anything other than head (SACK enhanced - * variant from Appendix B of RFC4138 is more robust here) +/* F-RTO can only be used if TCP has never retransmitted anything other than + * head (SACK enhanced variant from Appendix B of RFC4138 is more robust here) */ int tcp_use_frto(struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; - if (!sysctl_tcp_frto || !tcp_send_head(sk) || - after(TCP_SKB_CB(tcp_send_head(sk))->end_seq, - tp->snd_una + tp->snd_wnd)) + if (!sysctl_tcp_frto) return 0; if (IsSackFrto()) @@ -2710,6 +2705,14 @@ static int tcp_process_frto(struct sock *sk, u32 prior_snd_una, int flag) } if (tp->frto_counter == 1) { + /* Sending of the next skb must be allowed or no FRTO */ + if (!tcp_send_head(sk) || + after(TCP_SKB_CB(tcp_send_head(sk))->end_seq, + tp->snd_una + tp->snd_wnd)) { + tcp_enter_frto_loss(sk, tp->frto_counter + 1, flag); + return 1; + } + tp->snd_cwnd = tcp_packets_in_flight(tp) + 2; tp->frto_counter = 2; return 1; |