[PATCH 4/9] [TCP]: Access to highest_sack obsoletes forward_cnt_hint
From: Ilpo Järvinen <hidden>
Date: 2007-05-26 08:36:07
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
From: =?ISO-8859-1?q?Ilpo_J=E4rvinen?= <redacted> In addition, added a reference about the purpose of the loop. Signed-off-by: Ilpo Järvinen <redacted> --- include/linux/tcp.h | 1 - net/ipv4/tcp_output.c | 23 +++++++++-------------- 2 files changed, 9 insertions(+), 15 deletions(-)
diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 63e04f4..1ce9fd4 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h@@ -343,7 +343,6 @@ struct tcp_sock { int fastpath_cnt_hint; int retransmit_cnt_hint; - int forward_cnt_hint; u16 advmss; /* Advertised MSS */ u16 prior_ssthresh; /* ssthresh saved at recovery start */
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index d67fb3d..f33e25b 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c@@ -1931,33 +1931,28 @@ void tcp_xmit_retransmit_queue(struct sock *sk) * and retransmission... Both ways have their merits... * * For now we do not retransmit anything, while we have some new - * segments to send. + * segments to send. In the other cases, follow rule 3 for + * NextSeg() specified in RFC3517. */ if (tcp_may_send_now(sk)) return; - if (tp->forward_skb_hint) { + /* If nothing is SACKed, highest_sack in the loop won't be valid */ + if (!tp->sacked_out) + return; + + if (tp->forward_skb_hint) skb = tp->forward_skb_hint; - packet_cnt = tp->forward_cnt_hint; - } else{ + else skb = tcp_write_queue_head(sk); - packet_cnt = 0; - } tcp_for_write_queue_from(skb, sk) { if (skb == tcp_send_head(sk)) break; - tp->forward_cnt_hint = packet_cnt; tp->forward_skb_hint = skb; - /* Similar to the retransmit loop above we - * can pretend that the retransmitted SKB - * we send out here will be composed of one - * real MSS sized packet because tcp_retransmit_skb() - * will fragment it if necessary. - */ - if (++packet_cnt > tp->fackets_out) + if (after(TCP_SKB_CB(skb)->seq, tp->highest_sack)) break; if (tcp_packets_in_flight(tp) >= tp->snd_cwnd)
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1.5.0.6