From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neal Cardwell Subject: [PATCH 1/5] tcp: make is_dupack a parameter to tcp_fastretrans_alert() Date: Wed, 16 Nov 2011 13:58:01 -0500 Message-ID: <1321469885-10885-1-git-send-email-ncardwell@google.com> Cc: netdev@vger.kernel.org, ilpo.jarvinen@helsinki.fi, Nandita Dukkipati , Yuchung Cheng , Tom Herbert , Neal Cardwell To: David Miller Return-path: Received: from mail-wy0-f202.google.com ([74.125.82.202]:45634 "EHLO mail-wy0-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751907Ab1KPTDc (ORCPT ); Wed, 16 Nov 2011 14:03:32 -0500 Received: by wye20 with SMTP id 20so18915wye.1 for ; Wed, 16 Nov 2011 11:03:30 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: Allow callers to decide whether an ACK is a duplicate ACK. This is a prerequisite to allowing fastretrans_alert to be called from new contexts, such as the no_queue and old_ack code paths, from which we have extra info that tells us whether an ACK is a dupack. Signed-off-by: Neal Cardwell --- net/ipv4/tcp_input.c | 12 ++++++++---- 1 files changed, 8 insertions(+), 4 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 52b5c2d..f772aaa 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3009,11 +3009,11 @@ static void tcp_update_cwnd_in_recovery(struct sock *sk, int newly_acked_sacked, * tcp_xmit_retransmit_queue(). */ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked, - int newly_acked_sacked, int flag) + int newly_acked_sacked, bool is_dupack, + int flag) { struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); - int is_dupack = !(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP)); int do_lost = is_dupack || ((flag & FLAG_DATA_SACKED) && (tcp_fackets_out(tp) > tp->reordering)); int fast_rexmit = 0, mib_idx; @@ -3681,10 +3681,12 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) u32 prior_snd_una = tp->snd_una; u32 ack_seq = TCP_SKB_CB(skb)->seq; u32 ack = TCP_SKB_CB(skb)->ack_seq; + bool is_dupack = false; u32 prior_in_flight; u32 prior_fackets; int prior_packets; int prior_sacked = tp->sacked_out; + int pkts_acked = 0; int newly_acked_sacked = 0; int frto_cwnd = 0; @@ -3757,6 +3759,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) /* See if we can take anything off of the retransmit queue. */ flag |= tcp_clean_rtx_queue(sk, prior_fackets, prior_snd_una); + pkts_acked = prior_packets - tp->packets_out; newly_acked_sacked = (prior_packets - prior_sacked) - (tp->packets_out - tp->sacked_out); @@ -3771,8 +3774,9 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) if ((flag & FLAG_DATA_ACKED) && !frto_cwnd && tcp_may_raise_cwnd(sk, flag)) tcp_cong_avoid(sk, ack, prior_in_flight); - tcp_fastretrans_alert(sk, prior_packets - tp->packets_out, - newly_acked_sacked, flag); + is_dupack = !(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP)); + tcp_fastretrans_alert(sk, pkts_acked, newly_acked_sacked, + is_dupack, flag); } else { if ((flag & FLAG_DATA_ACKED) && !frto_cwnd) tcp_cong_avoid(sk, ack, prior_in_flight); -- 1.7.3.1