diff options
| -rw-r--r-- | net/ipv4/tcp_input.c | 80 |
1 files changed, 43 insertions, 37 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index e8c39488cf58..101054cb13e9 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1106,6 +1106,47 @@ static int tcp_is_sackblock_valid(struct tcp_sock *tp, int is_dsack, return !before(start_seq, end_seq - tp->max_window); } +/* Check for lost retransmit. This superb idea is borrowed from "ratehalving". + * Event "C". Later note: FACK people cheated me again 8), we have to account + * for reordering! Ugly, but should help. + */ +static int tcp_mark_lost_retrans(struct sock *sk, u32 lost_retrans) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct sk_buff *skb; + int flag = 0; + + tcp_for_write_queue(skb, sk) { + u32 ack_seq = TCP_SKB_CB(skb)->ack_seq; + + if (skb == tcp_send_head(sk)) + break; + if (after(TCP_SKB_CB(skb)->seq, lost_retrans)) + break; + if (!after(TCP_SKB_CB(skb)->end_seq, tp->snd_una)) + continue; + + if ((TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) && + after(lost_retrans, ack_seq) && + (tcp_is_fack(tp) || + !before(lost_retrans, + ack_seq + tp->reordering * tp->mss_cache))) { + TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS; + tp->retrans_out -= tcp_skb_pcount(skb); + + /* clear lost hint */ + tp->retransmit_skb_hint = NULL; + + if (!(TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_ACKED))) { + tp->lost_out += tcp_skb_pcount(skb); + TCP_SKB_CB(skb)->sacked |= TCPCB_LOST; + flag |= FLAG_DATA_SACKED; + NET_INC_STATS_BH(LINUX_MIB_TCPLOSTRETRANSMIT); + } + } + } + return flag; +} static int tcp_check_dsack(struct tcp_sock *tp, struct sk_buff *ack_skb, struct tcp_sack_block_wire *sp, int num_sacks, @@ -1422,43 +1463,8 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ } } - /* Check for lost retransmit. This superb idea is - * borrowed from "ratehalving". Event "C". - * Later note: FACK people cheated me again 8), - * we have to account for reordering! Ugly, - * but should help. - */ - if (lost_retrans && icsk->icsk_ca_state == TCP_CA_Recovery) { - struct sk_buff *skb; - - tcp_for_write_queue(skb, sk) { - if (skb == tcp_send_head(sk)) - break; - if (after(TCP_SKB_CB(skb)->seq, lost_retrans)) - break; - if (!after(TCP_SKB_CB(skb)->end_seq, tp->snd_una)) - continue; - if ((TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_RETRANS) && - after(lost_retrans, TCP_SKB_CB(skb)->ack_seq) && - (tcp_is_fack(tp) || - !before(lost_retrans, - TCP_SKB_CB(skb)->ack_seq + tp->reordering * - tp->mss_cache))) { - TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS; - tp->retrans_out -= tcp_skb_pcount(skb); - - /* clear lost hint */ - tp->retransmit_skb_hint = NULL; - - if (!(TCP_SKB_CB(skb)->sacked&(TCPCB_LOST|TCPCB_SACKED_ACKED))) { - tp->lost_out += tcp_skb_pcount(skb); - TCP_SKB_CB(skb)->sacked |= TCPCB_LOST; - flag |= FLAG_DATA_SACKED; - NET_INC_STATS_BH(LINUX_MIB_TCPLOSTRETRANSMIT); - } - } - } - } + if (lost_retrans && icsk->icsk_ca_state == TCP_CA_Recovery) + flag |= tcp_mark_lost_retrans(sk, lost_retrans); tcp_verify_left_out(tp); |