From fc6415bcb0f58f03adb910e56d7e1df6368794e0 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 5 Jul 2005 15:17:45 -0700 Subject: [PATCH] [TCP]: Fix quick-ack decrementing with TSO. On each packet output, we call tcp_dec_quickack_mode() if the ACK flag is set. It drops tp->ack.quick until it hits zero, at which time we deflate the ATO value. When doing TSO, we are emitting multiple packets with ACK set, so we should decrement tp->ack.quick that many segments. Note that, unlike this case, tcp_enter_cwr() should not take the tcp_skb_pcount(skb) into consideration. That function, one time, readjusts tp->snd_cwnd and moves into TCP_CA_CWR state. Signed-off-by: David S. Miller --- include/net/tcp.h | 13 +++++++++---- net/ipv4/tcp_output.c | 6 +++--- 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index ec9e20c27179..afe41c5de2f2 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -721,11 +721,16 @@ static inline int tcp_ack_scheduled(struct tcp_sock *tp) return tp->ack.pending&TCP_ACK_SCHED; } -static __inline__ void tcp_dec_quickack_mode(struct tcp_sock *tp) +static __inline__ void tcp_dec_quickack_mode(struct tcp_sock *tp, unsigned int pkts) { - if (tp->ack.quick && --tp->ack.quick == 0) { - /* Leaving quickack mode we deflate ATO. */ - tp->ack.ato = TCP_ATO_MIN; + if (tp->ack.quick) { + if (pkts >= tp->ack.quick) { + tp->ack.quick = 0; + + /* Leaving quickack mode we deflate ATO. */ + tp->ack.ato = TCP_ATO_MIN; + } else + tp->ack.quick -= pkts; } } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 0e17c244875c..389deeb2a457 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -140,11 +140,11 @@ static inline void tcp_event_data_sent(struct tcp_sock *tp, tp->ack.pingpong = 1; } -static __inline__ void tcp_event_ack_sent(struct sock *sk) +static __inline__ void tcp_event_ack_sent(struct sock *sk, unsigned int pkts) { struct tcp_sock *tp = tcp_sk(sk); - tcp_dec_quickack_mode(tp); + tcp_dec_quickack_mode(tp, pkts); tcp_clear_xmit_timer(sk, TCP_TIME_DACK); } @@ -355,7 +355,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb) tp->af_specific->send_check(sk, th, skb->len, skb); if (tcb->flags & TCPCB_FLAG_ACK) - tcp_event_ack_sent(sk); + tcp_event_ack_sent(sk, tcp_skb_pcount(skb)); if (skb->len != tcp_header_size) tcp_event_data_sent(tp, skb, sk); -- 2.20.1