diff options
| author | Eric Dumazet <[email protected]> | 2018-06-27 15:47:21 +0000 |
|---|---|---|
| committer | David S. Miller <[email protected]> | 2018-06-28 13:01:04 +0000 |
| commit | 15ecbe94a45ef88491ca459b26efdd02f91edb6d (patch) | |
| tree | def3573e62862a41bb840c8fcdca92665484131c /net/ipv4/tcp_input.c | |
| parent | bpfilter: include bpfilter_umh in assembly instead of using objcopy (diff) | |
| download | kernel-15ecbe94a45ef88491ca459b26efdd02f91edb6d.tar.gz kernel-15ecbe94a45ef88491ca459b26efdd02f91edb6d.zip | |
tcp: add one more quick ack after after ECN events
Larry Brakmo proposal ( https://patchwork.ozlabs.org/patch/935233/
tcp: force cwnd at least 2 in tcp_cwnd_reduction) made us rethink
about our recent patch removing ~16 quick acks after ECN events.
tcp_enter_quickack_mode(sk, 1) makes sure one immediate ack is sent,
but in the case the sender cwnd was lowered to 1, we do not want
to have a delayed ack for the next packet we will receive.
Fixes: 522040ea5fdd ("tcp: do not aggressively quick ack after ECN events")
Signed-off-by: Eric Dumazet <[email protected]>
Reported-by: Neal Cardwell <[email protected]>
Cc: Lawrence Brakmo <[email protected]>
Acked-by: Neal Cardwell <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 355d3dffd021..045d930d01a9 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -265,7 +265,7 @@ static void __tcp_ecn_check_ce(struct sock *sk, const struct sk_buff *skb) * it is probably a retransmit. */ if (tp->ecn_flags & TCP_ECN_SEEN) - tcp_enter_quickack_mode(sk, 1); + tcp_enter_quickack_mode(sk, 2); break; case INET_ECN_CE: if (tcp_ca_needs_ecn(sk)) @@ -273,7 +273,7 @@ static void __tcp_ecn_check_ce(struct sock *sk, const struct sk_buff *skb) if (!(tp->ecn_flags & TCP_ECN_DEMAND_CWR)) { /* Better not delay acks, sender can have a very low cwnd */ - tcp_enter_quickack_mode(sk, 1); + tcp_enter_quickack_mode(sk, 2); tp->ecn_flags |= TCP_ECN_DEMAND_CWR; } tp->ecn_flags |= TCP_ECN_SEEN; |