X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=net%2Fipv4%2Ftcp_output.c;h=b7325e0b406a8486fad7bc6da6b24f5ade426415;hb=dfb4b9dceb35c567a595ae5e9d035cfda044a103;hp=caf2e2cff29365ece4d1075ac2eae72c7bf12816;hpb=1dd465cac8d3ba18a9840d032f6604147269c031;p=linux-2.6-omap-h63xx.git diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index caf2e2cff29..b7325e0b406 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -194,12 +194,11 @@ void tcp_select_initial_window(int __space, __u32 mss, * will be satisfied with 2. */ if (mss > (1<<*rcv_wscale)) { - int init_cwnd; - - if (mss > 1460) + int init_cwnd = 4; + if (mss > 1460*3) init_cwnd = 2; - else - init_cwnd = (mss > 1095) ? 3 : 4; + else if (mss > 1460) + init_cwnd = 3; if (*rcv_wnd > init_cwnd*mss) *rcv_wnd = init_cwnd*mss; } @@ -263,122 +262,139 @@ static __inline__ u16 tcp_select_window(struct sock *sk) * We are working here with either a clone of the original * SKB, or a fresh unique copy made by the retransmit engine. */ -static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb) +static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, gfp_t gfp_mask) { - if (skb != NULL) { - const struct inet_connection_sock *icsk = inet_csk(sk); - struct inet_sock *inet = inet_sk(sk); - struct tcp_sock *tp = tcp_sk(sk); - struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); - int tcp_header_size = tp->tcp_header_len; - struct tcphdr *th; - int sysctl_flags; - int err; + const struct inet_connection_sock *icsk = inet_csk(sk); + struct inet_sock *inet; + struct tcp_sock *tp; + struct tcp_skb_cb *tcb; + int tcp_header_size; + struct tcphdr *th; + int sysctl_flags; + int err; + + BUG_ON(!skb || !tcp_skb_pcount(skb)); + + /* If congestion control is doing timestamping, we must + * take such a timestamp before we potentially clone/copy. + */ + if (icsk->icsk_ca_ops->rtt_sample) + __net_timestamp(skb); + + if (likely(clone_it)) { + if (unlikely(skb_cloned(skb))) + skb = pskb_copy(skb, gfp_mask); + else + skb = skb_clone(skb, gfp_mask); + if (unlikely(!skb)) + return -ENOBUFS; + } - BUG_ON(!tcp_skb_pcount(skb)); + inet = inet_sk(sk); + tp = tcp_sk(sk); + tcb = TCP_SKB_CB(skb); + tcp_header_size = tp->tcp_header_len; #define SYSCTL_FLAG_TSTAMPS 0x1 #define SYSCTL_FLAG_WSCALE 0x2 #define SYSCTL_FLAG_SACK 0x4 - /* If congestion control is doing timestamping */ - if (icsk->icsk_ca_ops->rtt_sample) - __net_timestamp(skb); - - sysctl_flags = 0; - if (tcb->flags & TCPCB_FLAG_SYN) { - tcp_header_size = sizeof(struct tcphdr) + TCPOLEN_MSS; - if(sysctl_tcp_timestamps) { - tcp_header_size += TCPOLEN_TSTAMP_ALIGNED; - sysctl_flags |= SYSCTL_FLAG_TSTAMPS; - } - if(sysctl_tcp_window_scaling) { - tcp_header_size += TCPOLEN_WSCALE_ALIGNED; - sysctl_flags |= SYSCTL_FLAG_WSCALE; - } - if(sysctl_tcp_sack) { - sysctl_flags |= SYSCTL_FLAG_SACK; - if(!(sysctl_flags & SYSCTL_FLAG_TSTAMPS)) - tcp_header_size += TCPOLEN_SACKPERM_ALIGNED; - } - } else if (tp->rx_opt.eff_sacks) { - /* A SACK is 2 pad bytes, a 2 byte header, plus - * 2 32-bit sequence numbers for each SACK block. - */ - tcp_header_size += (TCPOLEN_SACK_BASE_ALIGNED + - (tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK)); + sysctl_flags = 0; + if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) { + tcp_header_size = sizeof(struct tcphdr) + TCPOLEN_MSS; + if(sysctl_tcp_timestamps) { + tcp_header_size += TCPOLEN_TSTAMP_ALIGNED; + sysctl_flags |= SYSCTL_FLAG_TSTAMPS; } - - if (tcp_packets_in_flight(tp) == 0) - tcp_ca_event(sk, CA_EVENT_TX_START); - - th = (struct tcphdr *) skb_push(skb, tcp_header_size); - skb->h.th = th; - skb_set_owner_w(skb, sk); - - /* Build TCP header and checksum it. */ - th->source = inet->sport; - th->dest = inet->dport; - th->seq = htonl(tcb->seq); - th->ack_seq = htonl(tp->rcv_nxt); - *(((__u16 *)th) + 6) = htons(((tcp_header_size >> 2) << 12) | tcb->flags); - if (tcb->flags & TCPCB_FLAG_SYN) { - /* RFC1323: The window in SYN & SYN/ACK segments - * is never scaled. - */ - th->window = htons(tp->rcv_wnd); - } else { - th->window = htons(tcp_select_window(sk)); + if (sysctl_tcp_window_scaling) { + tcp_header_size += TCPOLEN_WSCALE_ALIGNED; + sysctl_flags |= SYSCTL_FLAG_WSCALE; } - th->check = 0; - th->urg_ptr = 0; - - if (tp->urg_mode && - between(tp->snd_up, tcb->seq+1, tcb->seq+0xFFFF)) { - th->urg_ptr = htons(tp->snd_up-tcb->seq); - th->urg = 1; + if (sysctl_tcp_sack) { + sysctl_flags |= SYSCTL_FLAG_SACK; + if (!(sysctl_flags & SYSCTL_FLAG_TSTAMPS)) + tcp_header_size += TCPOLEN_SACKPERM_ALIGNED; } + } else if (unlikely(tp->rx_opt.eff_sacks)) { + /* A SACK is 2 pad bytes, a 2 byte header, plus + * 2 32-bit sequence numbers for each SACK block. + */ + tcp_header_size += (TCPOLEN_SACK_BASE_ALIGNED + + (tp->rx_opt.eff_sacks * + TCPOLEN_SACK_PERBLOCK)); + } + + if (tcp_packets_in_flight(tp) == 0) + tcp_ca_event(sk, CA_EVENT_TX_START); + + th = (struct tcphdr *) skb_push(skb, tcp_header_size); + skb->h.th = th; + skb_set_owner_w(skb, sk); + + /* Build TCP header and checksum it. */ + th->source = inet->sport; + th->dest = inet->dport; + th->seq = htonl(tcb->seq); + th->ack_seq = htonl(tp->rcv_nxt); + *(((__u16 *)th) + 6) = htons(((tcp_header_size >> 2) << 12) | + tcb->flags); + + if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) { + /* RFC1323: The window in SYN & SYN/ACK segments + * is never scaled. + */ + th->window = htons(tp->rcv_wnd); + } else { + th->window = htons(tcp_select_window(sk)); + } + th->check = 0; + th->urg_ptr = 0; - if (tcb->flags & TCPCB_FLAG_SYN) { - tcp_syn_build_options((__u32 *)(th + 1), - tcp_advertise_mss(sk), - (sysctl_flags & SYSCTL_FLAG_TSTAMPS), - (sysctl_flags & SYSCTL_FLAG_SACK), - (sysctl_flags & SYSCTL_FLAG_WSCALE), - tp->rx_opt.rcv_wscale, - tcb->when, - tp->rx_opt.ts_recent); - } else { - tcp_build_and_update_options((__u32 *)(th + 1), - tp, tcb->when); + if (unlikely(tp->urg_mode && + between(tp->snd_up, tcb->seq+1, tcb->seq+0xFFFF))) { + th->urg_ptr = htons(tp->snd_up-tcb->seq); + th->urg = 1; + } - TCP_ECN_send(sk, tp, skb, tcp_header_size); - } - tp->af_specific->send_check(sk, th, skb->len, skb); + if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) { + tcp_syn_build_options((__u32 *)(th + 1), + tcp_advertise_mss(sk), + (sysctl_flags & SYSCTL_FLAG_TSTAMPS), + (sysctl_flags & SYSCTL_FLAG_SACK), + (sysctl_flags & SYSCTL_FLAG_WSCALE), + tp->rx_opt.rcv_wscale, + tcb->when, + tp->rx_opt.ts_recent); + } else { + tcp_build_and_update_options((__u32 *)(th + 1), + tp, tcb->when); + TCP_ECN_send(sk, tp, skb, tcp_header_size); + } - if (tcb->flags & TCPCB_FLAG_ACK) - tcp_event_ack_sent(sk, tcp_skb_pcount(skb)); + tp->af_specific->send_check(sk, th, skb->len, skb); - if (skb->len != tcp_header_size) - tcp_event_data_sent(tp, skb, sk); + if (likely(tcb->flags & TCPCB_FLAG_ACK)) + tcp_event_ack_sent(sk, tcp_skb_pcount(skb)); - TCP_INC_STATS(TCP_MIB_OUTSEGS); + if (skb->len != tcp_header_size) + tcp_event_data_sent(tp, skb, sk); - err = tp->af_specific->queue_xmit(skb, 0); - if (err <= 0) - return err; + TCP_INC_STATS(TCP_MIB_OUTSEGS); - tcp_enter_cwr(sk); + err = tp->af_specific->queue_xmit(skb, 0); + if (unlikely(err <= 0)) + return err; + + tcp_enter_cwr(sk); + + /* NET_XMIT_CN is special. It does not guarantee, + * that this packet is lost. It tells that device + * is about to start to drop packets or already + * drops some packets of the same priority and + * invokes us to send less aggressively. + */ + return err == NET_XMIT_CN ? 0 : err; - /* NET_XMIT_CN is special. It does not guarantee, - * that this packet is lost. It tells that device - * is about to start to drop packets or already - * drops some packets of the same priority and - * invokes us to send less aggressively. - */ - return err == NET_XMIT_CN ? 0 : err; - } - return -ENOBUFS; #undef SYSCTL_FLAG_TSTAMPS #undef SYSCTL_FLAG_WSCALE #undef SYSCTL_FLAG_SACK @@ -436,8 +452,9 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss int nsize, old_factor; u16 flags; - BUG_ON(len >= skb->len); + BUG_ON(len > skb->len); + clear_all_retrans_hints(tp); nsize = skb_headlen(skb) - len; if (nsize < 0) nsize = 0; @@ -601,7 +618,7 @@ 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. @@ -1036,7 +1053,7 @@ static int tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle) TCP_SKB_CB(skb)->when = tcp_time_stamp; - if (unlikely(tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)))) + if (unlikely(tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC))) break; /* Advance the send_head. This one is sent out. @@ -1109,7 +1126,7 @@ void tcp_push_one(struct sock *sk, unsigned int mss_now) /* Send it out now. */ TCP_SKB_CB(skb)->when = tcp_time_stamp; - if (likely(!tcp_transmit_skb(sk, skb_clone(skb, sk->sk_allocation)))) { + if (likely(!tcp_transmit_skb(sk, skb, 1, sk->sk_allocation))) { update_send_head(sk, tp, skb); tcp_cwnd_validate(sk, tp); return; @@ -1173,7 +1190,7 @@ 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 @@ -1262,7 +1279,10 @@ 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); @@ -1332,6 +1352,8 @@ void tcp_simple_retransmit(struct sock *sk) } } + clear_all_retrans_hints(tp); + if (!lost) return; @@ -1363,7 +1385,7 @@ 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)) @@ -1424,9 +1446,7 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb) */ TCP_SKB_CB(skb)->when = tcp_time_stamp; - err = tcp_transmit_skb(sk, (skb_cloned(skb) ? - pskb_copy(skb, GFP_ATOMIC): - skb_clone(skb, GFP_ATOMIC))); + err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC); if (err == 0) { /* Update global TCP statistics. */ @@ -1470,13 +1490,25 @@ 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 @@ -1487,10 +1519,12 @@ 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 @@ -1503,8 +1537,8 @@ 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; } } @@ -1530,9 +1564,18 @@ 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 @@ -1549,8 +1592,10 @@ 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, @@ -1611,7 +1656,7 @@ void tcp_send_fin(struct sock *sk) * was unread data in the receive queue. This behavior is recommended * by draft-ietf-tcpimpl-prob-03.txt section 3.10. -DaveM */ -void tcp_send_active_reset(struct sock *sk, unsigned int __nocast priority) +void tcp_send_active_reset(struct sock *sk, gfp_t priority) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; @@ -1635,7 +1680,7 @@ void tcp_send_active_reset(struct sock *sk, unsigned int __nocast priority) TCP_SKB_CB(skb)->seq = tcp_acceptable_seq(sk, tp); TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq; TCP_SKB_CB(skb)->when = tcp_time_stamp; - if (tcp_transmit_skb(sk, skb)) + if (tcp_transmit_skb(sk, skb, 0, priority)) NET_INC_STATS(LINUX_MIB_TCPABORTFAILED); } @@ -1670,7 +1715,7 @@ int tcp_send_synack(struct sock *sk) TCP_ECN_send_synack(tcp_sk(sk), skb); } TCP_SKB_CB(skb)->when = tcp_time_stamp; - return tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)); + return tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC); } /* @@ -1831,7 +1876,7 @@ int tcp_connect(struct sock *sk) __skb_queue_tail(&sk->sk_write_queue, buff); sk_charge_skb(sk, buff); tp->packets_out += tcp_skb_pcount(buff); - tcp_transmit_skb(sk, skb_clone(buff, GFP_KERNEL)); + tcp_transmit_skb(sk, buff, 1, GFP_KERNEL); TCP_INC_STATS(TCP_MIB_ACTIVEOPENS); /* Timer for repeating the SYN until an answer. */ @@ -1927,7 +1972,7 @@ void tcp_send_ack(struct sock *sk) /* Send it off, this clears delayed acks for us. */ TCP_SKB_CB(buff)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk, tp); TCP_SKB_CB(buff)->when = tcp_time_stamp; - tcp_transmit_skb(sk, buff); + tcp_transmit_skb(sk, buff, 0, GFP_ATOMIC); } } @@ -1967,7 +2012,7 @@ static int tcp_xmit_probe_skb(struct sock *sk, int urgent) TCP_SKB_CB(skb)->seq = urgent ? tp->snd_una : tp->snd_una - 1; TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq; TCP_SKB_CB(skb)->when = tcp_time_stamp; - return tcp_transmit_skb(sk, skb); + return tcp_transmit_skb(sk, skb, 0, GFP_ATOMIC); } int tcp_write_wakeup(struct sock *sk) @@ -2000,7 +2045,7 @@ int tcp_write_wakeup(struct sock *sk) TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH; TCP_SKB_CB(skb)->when = tcp_time_stamp; - err = tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)); + err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC); if (!err) { update_send_head(sk, tp, skb); } @@ -2060,3 +2105,4 @@ 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);