From 006f582c73f4eda35e06fd323193c3df43fb3459 Mon Sep 17 00:00:00 2001 From: Ilpo Järvinen Date: Sat, 20 Sep 2008 21:20:20 -0700 Subject: tcp: convert retransmit_cnt_hint to seqno MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Main benefit in this is that we can then freely point the retransmit_skb_hint to anywhere we want to because there's no longer need to know what would be the count changes involve, and since this is really used only as a terminator, unnecessary work is one time walk at most, and if some retransmissions are necessary after that point later on, the walk is not full waste of time anyway. Since retransmit_high must be kept valid, all lost markers must ensure that. Now I also have learned how those "holes" in the rexmittable skbs can appear, mtu probe does them. So I removed the misleading comment as well. Signed-off-by: Ilpo Järvinen Signed-off-by: David S. Miller --- net/ipv4/tcp_output.c | 25 +++++++------------------ 1 file changed, 7 insertions(+), 18 deletions(-) (limited to 'net/ipv4/tcp_output.c') diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 11490958a096..cfae61b40c44 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1838,7 +1838,7 @@ void tcp_simple_retransmit(struct sock *sk) struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; unsigned int mss = tcp_current_mss(sk, 0); - int lost = 0; + u32 prior_lost = tp->lost_out; tcp_for_write_queue(skb, sk) { if (skb == tcp_send_head(sk)) @@ -1849,17 +1849,13 @@ void tcp_simple_retransmit(struct sock *sk) TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS; tp->retrans_out -= tcp_skb_pcount(skb); } - if (!(TCP_SKB_CB(skb)->sacked & TCPCB_LOST)) { - TCP_SKB_CB(skb)->sacked |= TCPCB_LOST; - tp->lost_out += tcp_skb_pcount(skb); - lost = 1; - } + tcp_skb_mark_lost_uncond_verify(tp, skb); } } tcp_clear_all_retrans_hints(tp); - if (!lost) + if (prior_lost == tp->lost_out) return; if (tcp_is_reno(tp)) @@ -2009,15 +2005,11 @@ 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; - if (tp->retransmit_skb_hint) { + if (tp->retransmit_skb_hint) skb = tp->retransmit_skb_hint; - packet_cnt = tp->retransmit_cnt_hint; - } else { + else skb = tcp_write_queue_head(sk); - packet_cnt = 0; - } /* First pass: retransmit lost packets. */ if (tp->lost_out) { @@ -2028,7 +2020,6 @@ void tcp_xmit_retransmit_queue(struct sock *sk) break; /* 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 @@ -2039,6 +2030,8 @@ 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_LOST) { if (!(sacked & (TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS))) { @@ -2059,10 +2052,6 @@ void tcp_xmit_retransmit_queue(struct sock *sk) inet_csk(sk)->icsk_rto, TCP_RTO_MAX); } - - packet_cnt += tcp_skb_pcount(skb); - if (packet_cnt >= tp->lost_out) - break; } } } -- cgit v1.2.3