From d738cd8fca948e45d53120247cb7a5f5be3ca09e Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ilpo=20J=C3=A4rvinen?= Date: Sat, 24 Mar 2007 21:03:23 -0700 Subject: [PATCH] [TCP]: Add highest_sack seqno, points to globally highest SACK MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit It is guaranteed to be valid only when !tp->sacked_out. In most cases this seqno is available in the last ACK but there is no guarantee for that. The new fast recovery loss marking algorithm needs this as entry point. Signed-off-by: Ilpo Järvinen Signed-off-by: David S. Miller --- include/linux/tcp.h | 2 ++ net/ipv4/tcp_input.c | 8 +++++++- 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/include/linux/tcp.h b/include/linux/tcp.h index c6b9f92..c072f88 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -333,6 +333,8 @@ struct tcp_sock { struct tcp_sack_block_wire recv_sack_cache[4]; + u32 highest_sack; /* Start seq of globally highest revd SACK (valid only in slowpath) */ + /* from STCP, retrans queue hinting */ struct sk_buff* lost_skb_hint; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index f893e90..813f204 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -979,8 +979,10 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ int i; int first_sack_index; - if (!tp->sacked_out) + if (!tp->sacked_out) { tp->fackets_out = 0; + tp->highest_sack = tp->snd_una; + } prior_fackets = tp->fackets_out; /* Check for D-SACK. */ @@ -1217,6 +1219,10 @@ 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)) + tp->highest_sack = TCP_SKB_CB(skb)->seq; } else { if (dup_sack && (sacked&TCPCB_RETRANS)) reord = min(fack_count, reord); -- 2.7.4