diff options
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 61 |
1 files changed, 47 insertions, 14 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index b907456a79f..029c70dfb58 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -436,6 +436,8 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss u16 flags; BUG_ON(len > skb->len); + + clear_all_retrans_hints(tp); nsize = skb_headlen(skb) - len; if (nsize < 0) nsize = 0; @@ -599,7 +601,7 @@ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len) for TCP options, but includes only bare TCP header. tp->rx_opt.mss_clamp is mss negotiated at connection setup. - It is minumum of user_mss and mss received with SYN. + It is minimum of user_mss and mss received with SYN. It also does not include TCP options. tp->pmtu_cookie is last pmtu, seen by this function. @@ -1171,7 +1173,7 @@ u32 __tcp_select_window(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); - /* MSS for the peer's data. Previous verions used mss_clamp + /* MSS for the peer's data. Previous versions used mss_clamp * here. I don't know if the value based on our guesses * of peer's MSS is better for the performance. It's more correct * but may be worse for the performance because of rcv_mss @@ -1260,7 +1262,10 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m BUG_ON(tcp_skb_pcount(skb) != 1 || tcp_skb_pcount(next_skb) != 1); - /* Ok. We will be able to collapse the packet. */ + /* changing transmit queue under us so clear hints */ + clear_all_retrans_hints(tp); + + /* Ok. We will be able to collapse the packet. */ __skb_unlink(next_skb, &sk->sk_write_queue); memcpy(skb_put(skb, next_skb_size), next_skb->data, next_skb_size); @@ -1330,6 +1335,8 @@ void tcp_simple_retransmit(struct sock *sk) } } + clear_all_retrans_hints(tp); + if (!lost) return; @@ -1361,7 +1368,7 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb) int err; /* Do not sent more than we queued. 1/4 is reserved for possible - * copying overhead: frgagmentation, tunneling, mangling etc. + * copying overhead: fragmentation, tunneling, mangling etc. */ if (atomic_read(&sk->sk_wmem_alloc) > min(sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2), sk->sk_sndbuf)) @@ -1468,13 +1475,25 @@ void tcp_xmit_retransmit_queue(struct sock *sk) const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; - int packet_cnt = tp->lost_out; + int packet_cnt; + + if (tp->retransmit_skb_hint) { + skb = tp->retransmit_skb_hint; + packet_cnt = tp->retransmit_cnt_hint; + }else{ + skb = sk->sk_write_queue.next; + packet_cnt = 0; + } /* First pass: retransmit lost packets. */ - if (packet_cnt) { - sk_stream_for_retrans_queue(skb, sk) { + if (tp->lost_out) { + sk_stream_for_retrans_queue_from(skb, sk) { __u8 sacked = TCP_SKB_CB(skb)->sacked; + /* we could do better than to assign each time */ + tp->retransmit_skb_hint = skb; + tp->retransmit_cnt_hint = packet_cnt; + /* Assume this retransmit will generate * only one packet for congestion window * calculation purposes. This works because @@ -1485,10 +1504,12 @@ void tcp_xmit_retransmit_queue(struct sock *sk) if (tcp_packets_in_flight(tp) >= tp->snd_cwnd) return; - if (sacked&TCPCB_LOST) { + if (sacked & TCPCB_LOST) { if (!(sacked&(TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS))) { - if (tcp_retransmit_skb(sk, skb)) + if (tcp_retransmit_skb(sk, skb)) { + tp->retransmit_skb_hint = NULL; return; + } if (icsk->icsk_ca_state != TCP_CA_Loss) NET_INC_STATS_BH(LINUX_MIB_TCPFASTRETRANS); else @@ -1501,8 +1522,8 @@ void tcp_xmit_retransmit_queue(struct sock *sk) TCP_RTO_MAX); } - packet_cnt -= tcp_skb_pcount(skb); - if (packet_cnt <= 0) + packet_cnt += tcp_skb_pcount(skb); + if (packet_cnt >= tp->lost_out) break; } } @@ -1528,9 +1549,18 @@ void tcp_xmit_retransmit_queue(struct sock *sk) if (tcp_may_send_now(sk, tp)) return; - packet_cnt = 0; + if (tp->forward_skb_hint) { + skb = tp->forward_skb_hint; + packet_cnt = tp->forward_cnt_hint; + } else{ + skb = sk->sk_write_queue.next; + packet_cnt = 0; + } + + sk_stream_for_retrans_queue_from(skb, sk) { + tp->forward_cnt_hint = packet_cnt; + tp->forward_skb_hint = skb; - sk_stream_for_retrans_queue(skb, sk) { /* Similar to the retransmit loop above we * can pretend that the retransmitted SKB * we send out here will be composed of one @@ -1547,8 +1577,10 @@ void tcp_xmit_retransmit_queue(struct sock *sk) continue; /* Ok, retransmit it. */ - if (tcp_retransmit_skb(sk, skb)) + if (tcp_retransmit_skb(sk, skb)) { + tp->forward_skb_hint = NULL; break; + } if (skb == skb_peek(&sk->sk_write_queue)) inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, @@ -2058,3 +2090,4 @@ EXPORT_SYMBOL(tcp_connect); EXPORT_SYMBOL(tcp_make_synack); EXPORT_SYMBOL(tcp_simple_retransmit); EXPORT_SYMBOL(tcp_sync_mss); +EXPORT_SYMBOL(sysctl_tcp_tso_win_divisor); |