From 9f58f3b721f52a4d3f497ea57f830ccd307f1d76 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ilpo=20J=C3=A4rvinen?= Date: Thu, 15 Nov 2007 19:42:54 -0800 Subject: [PATCH] [TCP]: Make lost retrans detection more self-contained MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Highest_sack_end_seq is no longer calculated in the loop, thus it can be pushed to the worker function altogether making that function independent of the sacktag. Signed-off-by: Ilpo Järvinen Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 31294b52ad42..7a2bfd85fff0 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1115,16 +1115,23 @@ static int tcp_is_sackblock_valid(struct tcp_sock *tp, int is_dsack, * * 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). Also calculate the lowest snd_nxt among the - * remaining retransmitted skbs to avoid some costly processing per ACKs. + * highest SACK block). Also calculate the lowest snd_nxt among the remaining + * retransmitted skbs to avoid some costly processing per ACKs. */ -static int tcp_mark_lost_retrans(struct sock *sk, u32 received_upto) +static int tcp_mark_lost_retrans(struct sock *sk) { + const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; int flag = 0; int cnt = 0; u32 new_low_seq = tp->snd_nxt; + u32 received_upto = TCP_SKB_CB(tp->highest_sack)->end_seq; + + if (!tcp_is_fack(tp) || !tp->retrans_out || + !after(received_upto, tp->lost_retrans_low) || + icsk->icsk_ca_state != TCP_CA_Recovery) + return flag; tcp_for_write_queue(skb, sk) { u32 ack_seq = TCP_SKB_CB(skb)->ack_seq; @@ -1245,7 +1252,6 @@ 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 highest_sack_end_seq; int flag = 0; int found_dup_sack = 0; int cached_fack_count; @@ -1513,11 +1519,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ flag &= ~FLAG_ONLY_ORIG_SACKED; } - highest_sack_end_seq = TCP_SKB_CB(tp->highest_sack)->end_seq; - if (tcp_is_fack(tp) && tp->retrans_out && - after(highest_sack_end_seq, tp->lost_retrans_low) && - icsk->icsk_ca_state == TCP_CA_Recovery) - flag |= tcp_mark_lost_retrans(sk, highest_sack_end_seq); + flag |= tcp_mark_lost_retrans(sk); tcp_verify_left_out(tp); -- 2.20.1