diff options
| author | Yuchung Cheng <ycheng@google.com> | 2012-05-02 17:30:04 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-05-03 04:56:10 +0400 |
| commit | 750ea2bafa55aaed208b2583470ecd7122225634 (patch) | |
| tree | 7656d7697566b0cecc7fbbdd8dbae288bca6d7e3 /include | |
| parent | eed530b6c67624db3f2cf477bac7c4d005d8f7ba (diff) | |
| download | linux-750ea2bafa55aaed208b2583470ecd7122225634.tar.xz | |
tcp: early retransmit: delayed fast retransmit
Implementing the advanced early retransmit (sysctl_tcp_early_retrans==2).
Delays the fast retransmit by an interval of RTT/4. We borrow the
RTO timer to implement the delay. If we receive another ACK or send
a new packet, the timer is cancelled and restored to original RTO
value offset by time elapsed. When the delayed-ER timer fires,
we enter fast recovery and perform fast retransmit.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/tcp.h | 3 | ||||
| -rw-r--r-- | include/net/tcp.h | 3 |
2 files changed, 5 insertions, 1 deletions
diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 7859b416d46e..d9b42c5be088 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -372,7 +372,8 @@ struct tcp_sock { repair : 1, unused : 1; u8 repair_queue; - u8 do_early_retrans:1;/* Enable RFC5827 early-retransmit */ + u8 do_early_retrans:1,/* Enable RFC5827 early-retransmit */ + early_retrans_delayed:1; /* Delayed ER timer installed */ /* RTT measurement */ u32 srtt; /* smoothed round trip time << 3 */ diff --git a/include/net/tcp.h b/include/net/tcp.h index 685437a16c97..5283aa4bfa23 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -500,6 +500,8 @@ extern void tcp_send_delayed_ack(struct sock *sk); /* tcp_input.c */ extern void tcp_cwnd_application_limited(struct sock *sk); +extern void tcp_resume_early_retransmit(struct sock *sk); +extern void tcp_rearm_rto(struct sock *sk); /* tcp_timer.c */ extern void tcp_init_xmit_timers(struct sock *); @@ -805,6 +807,7 @@ static inline void tcp_enable_early_retrans(struct tcp_sock *tp) { tp->do_early_retrans = sysctl_tcp_early_retrans && !sysctl_tcp_thin_dupack && sysctl_tcp_reordering == 3; + tp->early_retrans_delayed = 0; } static inline void tcp_disable_early_retrans(struct tcp_sock *tp) |