diff options
| -rw-r--r-- | net/ipv4/tcp_input.c | 37 |
1 files changed, 22 insertions, 15 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a0660391213..d5e0fcc22a3 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1109,27 +1109,34 @@ static int tcp_is_sackblock_valid(struct tcp_sock *tp, int is_dsack, /* 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. + * + * Search retransmitted skbs from write_queue that were sent when snd_nxt was + * less than what is now known to be received by the other end (derived from + * SACK blocks by the caller). */ -static int tcp_mark_lost_retrans(struct sock *sk, u32 lost_retrans) +static int tcp_mark_lost_retrans(struct sock *sk, u32 received_upto) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; int flag = 0; + int cnt = 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)) + if (cnt == tp->retrans_out) 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) && + if (!(TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS)) + continue; + + if (after(received_upto, ack_seq) && (tcp_is_fack(tp) || - !before(lost_retrans, + !before(received_upto, ack_seq + tp->reordering * tp->mss_cache))) { TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS; tp->retrans_out -= tcp_skb_pcount(skb); @@ -1143,6 +1150,8 @@ static int tcp_mark_lost_retrans(struct sock *sk, u32 lost_retrans) flag |= FLAG_DATA_SACKED; NET_INC_STATS_BH(LINUX_MIB_TCPLOSTRETRANSMIT); } + } else { + cnt += tcp_skb_pcount(skb); } } return flag; @@ -1225,7 +1234,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ int num_sacks = (ptr[1] - TCPOLEN_SACK_BASE)>>3; int reord = tp->packets_out; int prior_fackets; - u32 lost_retrans = 0; + u32 highest_sack_end_seq = 0; int flag = 0; int found_dup_sack = 0; int cached_fack_count; @@ -1396,11 +1405,6 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ continue; } - if ((sacked&TCPCB_SACKED_RETRANS) && - after(end_seq, TCP_SKB_CB(skb)->ack_seq) && - (!lost_retrans || after(end_seq, lost_retrans))) - lost_retrans = end_seq; - if (!in_sack) continue; @@ -1454,9 +1458,10 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ if (fack_count > tp->fackets_out) tp->fackets_out = fack_count; - if (after(TCP_SKB_CB(skb)->seq, - tp->highest_sack)) + if (after(TCP_SKB_CB(skb)->seq, tp->highest_sack)) { tp->highest_sack = TCP_SKB_CB(skb)->seq; + highest_sack_end_seq = TCP_SKB_CB(skb)->end_seq; + } } else { if (dup_sack && (sacked&TCPCB_RETRANS)) reord = min(fack_count, reord); @@ -1476,8 +1481,10 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ } } - if (lost_retrans && icsk->icsk_ca_state == TCP_CA_Recovery) - flag |= tcp_mark_lost_retrans(sk, lost_retrans); + if (tp->retrans_out && highest_sack_end_seq && + after(highest_sack_end_seq, tp->high_seq) && + icsk->icsk_ca_state == TCP_CA_Recovery) + flag |= tcp_mark_lost_retrans(sk, highest_sack_end_seq); tcp_verify_left_out(tp); |