diff options
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 79 |
1 files changed, 49 insertions, 30 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 5e63ed09658d..a6375ca2a59e 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -511,35 +511,6 @@ static inline int tcp_skb_is_last(const struct sock *sk, return skb->next == (struct sk_buff *)&sk->sk_write_queue; } -/* Push out any pending frames which were held back due to - * TCP_CORK or attempt at coalescing tiny packets. - * The socket must be locked by the caller. - */ -void __tcp_push_pending_frames(struct sock *sk, struct tcp_sock *tp, - unsigned cur_mss, int nonagle) -{ - struct sk_buff *skb = sk->sk_send_head; - - if (skb) { - if (!tcp_skb_is_last(sk, skb)) - nonagle = TCP_NAGLE_PUSH; - if (!tcp_snd_test(sk, skb, cur_mss, nonagle) || - tcp_write_xmit(sk, nonagle)) - tcp_check_probe_timer(sk, tp); - } - tcp_cwnd_validate(sk, tp); -} - -void __tcp_data_snd_check(struct sock *sk, struct sk_buff *skb) -{ - struct tcp_sock *tp = tcp_sk(sk); - - if (after(TCP_SKB_CB(skb)->end_seq, tp->snd_una + tp->snd_wnd) || - tcp_packets_in_flight(tp) >= tp->snd_cwnd || - tcp_write_xmit(sk, tp->nonagle)) - tcp_check_probe_timer(sk, tp); -} - int tcp_may_send_now(struct sock *sk, struct tcp_sock *tp) { struct sk_buff *skb = sk->sk_send_head; @@ -841,6 +812,26 @@ unsigned int tcp_current_mss(struct sock *sk, int large) return mss_now; } +/* Congestion window validation. (RFC2861) */ + +static inline void tcp_cwnd_validate(struct sock *sk, struct tcp_sock *tp) +{ + __u32 packets_out = tp->packets_out; + + if (packets_out >= tp->snd_cwnd) { + /* Network is feed fully. */ + tp->snd_cwnd_used = 0; + tp->snd_cwnd_stamp = tcp_time_stamp; + } else { + /* Network starves. */ + if (tp->packets_out > tp->snd_cwnd_used) + tp->snd_cwnd_used = tp->packets_out; + + if ((s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >= tp->rto) + tcp_cwnd_application_limited(sk); + } +} + /* This routine writes packets to the network. It advances the * send_head. This happens as incoming acks open up the remote * window for us. @@ -848,7 +839,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large) * Returns 1, if no segments are in flight and we have queued segments, but * cannot send anything now because of SWS or another problem. */ -int tcp_write_xmit(struct sock *sk, int nonagle) +static int tcp_write_xmit(struct sock *sk, int nonagle) { struct tcp_sock *tp = tcp_sk(sk); unsigned int mss_now; @@ -901,6 +892,34 @@ int tcp_write_xmit(struct sock *sk, int nonagle) return 0; } +/* Push out any pending frames which were held back due to + * TCP_CORK or attempt at coalescing tiny packets. + * The socket must be locked by the caller. + */ +void __tcp_push_pending_frames(struct sock *sk, struct tcp_sock *tp, + unsigned cur_mss, int nonagle) +{ + struct sk_buff *skb = sk->sk_send_head; + + if (skb) { + if (!tcp_skb_is_last(sk, skb)) + nonagle = TCP_NAGLE_PUSH; + if (!tcp_snd_test(sk, skb, cur_mss, nonagle) || + tcp_write_xmit(sk, nonagle)) + tcp_check_probe_timer(sk, tp); + } +} + +void __tcp_data_snd_check(struct sock *sk, struct sk_buff *skb) +{ + struct tcp_sock *tp = tcp_sk(sk); + + if (after(TCP_SKB_CB(skb)->end_seq, tp->snd_una + tp->snd_wnd) || + tcp_packets_in_flight(tp) >= tp->snd_cwnd || + tcp_write_xmit(sk, tp->nonagle)) + tcp_check_probe_timer(sk, tp); +} + /* This function returns the amount that we can raise the * usable window based on the following constraints * |