nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

[TCP]: Fix quick-ack decrementing with TSO.

Browse source 
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 <davem@davemloft.net>
This commit is contained in:
David S. Miller 2005-07-05 15:17:45 -07:00
parent c65f7f00c5
commit fc6415bcb0
2 changed files with 12 additions and 7 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

9
include/net/tcp.h
View file

@ -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) {
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;
}
}

6
net/ipv4/tcp_output.c
View file

@ -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);