diff options
author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2008-09-21 04:24:21 (GMT) |
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committer | David S. Miller <davem@davemloft.net> | 2008-09-21 04:24:21 (GMT) |
commit | 0e1c54c2a405494281e0639aacc90db03b50ae77 (patch) | |
tree | ba5098bdf80603d4b5aa74af11738620f2ea7681 /net/ipv4 | |
parent | 08ebd1721ab8fd362e90ae17b461c07b23fa2824 (diff) | |
download | linux-0e1c54c2a405494281e0639aacc90db03b50ae77.tar.xz |
tcp: reorganize retransmit code loops
Both loops are quite similar, so they can be combined
with little effort. As a result, forward_skb_hint becomes
obsolete as well.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
-rw-r--r-- | net/ipv4/tcp_output.c | 79 |
1 files changed, 33 insertions, 46 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 9f44be6..b5b4ddc 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2032,7 +2032,9 @@ 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; + struct sk_buff *hole = NULL; int mib_idx; + int fwd_rexmitting = 0; if (!tp->lost_out) tp->retransmit_high = tp->snd_una; @@ -2049,7 +2051,8 @@ void tcp_xmit_retransmit_queue(struct sock *sk) if (skb == tcp_send_head(sk)) break; /* we could do better than to assign each time */ - tp->retransmit_skb_hint = skb; + if (hole == NULL) + tp->retransmit_skb_hint = skb; /* Assume this retransmit will generate * only one packet for congestion window @@ -2060,65 +2063,49 @@ void tcp_xmit_retransmit_queue(struct sock *sk) */ if (tcp_packets_in_flight(tp) >= tp->snd_cwnd) return; - if (!before(TCP_SKB_CB(skb)->seq, tp->retransmit_high)) - break; - if (sacked & (TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS)) - continue; - - if (!(sacked & TCPCB_LOST)) - continue; - - if (tcp_retransmit_skb(sk, skb)) { - tp->retransmit_skb_hint = NULL; - return; - } - if (icsk->icsk_ca_state != TCP_CA_Loss) - mib_idx = LINUX_MIB_TCPFASTRETRANS; - else - mib_idx = LINUX_MIB_TCPSLOWSTARTRETRANS; - NET_INC_STATS_BH(sock_net(sk), mib_idx); - - if (skb == tcp_write_queue_head(sk)) - inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, - inet_csk(sk)->icsk_rto, - TCP_RTO_MAX); - } - - /* OK, demanded retransmission is finished. */ - if (!tcp_can_forward_retransmit(sk)) - return; - if (tp->forward_skb_hint) - skb = tp->forward_skb_hint; - else - skb = tcp_write_queue_head(sk); + if (fwd_rexmitting) { +begin_fwd: + if (!before(TCP_SKB_CB(skb)->seq, tcp_highest_sack_seq(tp))) + break; + mib_idx = LINUX_MIB_TCPFORWARDRETRANS; - tcp_for_write_queue_from(skb, sk) { - if (skb == tcp_send_head(sk)) - break; - tp->forward_skb_hint = skb; + } else if (!before(TCP_SKB_CB(skb)->seq, tp->retransmit_high)) { + if (!tcp_can_forward_retransmit(sk)) + break; + /* Backtrack if necessary to non-L'ed skb */ + if (hole != NULL) { + skb = hole; + hole = NULL; + } + fwd_rexmitting = 1; + goto begin_fwd; - if (!before(TCP_SKB_CB(skb)->seq, tcp_highest_sack_seq(tp))) - break; + } else if (!(sacked & TCPCB_LOST)) { + if (hole == NULL && !(sacked & TCPCB_SACKED_RETRANS)) + hole = skb; + continue; - if (tcp_packets_in_flight(tp) >= tp->snd_cwnd) - break; + } else { + if (icsk->icsk_ca_state != TCP_CA_Loss) + mib_idx = LINUX_MIB_TCPFASTRETRANS; + else + mib_idx = LINUX_MIB_TCPSLOWSTARTRETRANS; + } - if (TCP_SKB_CB(skb)->sacked & TCPCB_TAGBITS) + if (sacked & (TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS)) continue; - /* Ok, retransmit it. */ if (tcp_retransmit_skb(sk, skb)) { - tp->forward_skb_hint = NULL; - break; + tp->retransmit_skb_hint = NULL; + return; } + NET_INC_STATS_BH(sock_net(sk), mib_idx); if (skb == tcp_write_queue_head(sk)) inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, inet_csk(sk)->icsk_rto, TCP_RTO_MAX); - - NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPFORWARDRETRANS); } } |