From 9890092e46b2996bb85f7f973e69424cb5c07bc0 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 26 Sep 2014 22:37:35 +0200 Subject: net: tcp: more detailed ACK events and events for CE marked packets DataCenter TCP (DCTCP) determines cwnd growth based on ECN information and ACK properties, e.g. ACK that updates window is treated differently than DUPACK. Also DCTCP needs information whether ACK was delayed ACK. Furthermore, DCTCP also implements a CE state machine that keeps track of CE markings of incoming packets. Therefore, extend the congestion control framework to provide these event types, so that DCTCP can be properly implemented as a normal congestion algorithm module outside of the core stack. Joint work with Daniel Borkmann and Glenn Judd. Signed-off-by: Florian Westphal Signed-off-by: Daniel Borkmann Signed-off-by: Glenn Judd Acked-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/ipv4/tcp_output.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/ipv4/tcp_output.c') diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 20e73271d75c..124f9e4e4594 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3130,6 +3130,8 @@ void tcp_send_delayed_ack(struct sock *sk) int ato = icsk->icsk_ack.ato; unsigned long timeout; + tcp_ca_event(sk, CA_EVENT_DELAYED_ACK); + if (ato > TCP_DELACK_MIN) { const struct tcp_sock *tp = tcp_sk(sk); int max_ato = HZ / 2; @@ -3186,6 +3188,8 @@ void tcp_send_ack(struct sock *sk) if (sk->sk_state == TCP_CLOSE) return; + tcp_ca_event(sk, CA_EVENT_NON_DELAYED_ACK); + /* We are not putting this on the write queue, so * tcp_transmit_skb() will set the ownership to this * sock. -- cgit v1.2.3