From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- net/ipv4/tcp_scalable.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 net/ipv4/tcp_scalable.c (limited to 'net/ipv4/tcp_scalable.c') diff --git a/net/ipv4/tcp_scalable.c b/net/ipv4/tcp_scalable.c new file mode 100644 index 000000000..333bcb241 --- /dev/null +++ b/net/ipv4/tcp_scalable.c @@ -0,0 +1,62 @@ +/* Tom Kelly's Scalable TCP + * + * See http://www.deneholme.net/tom/scalable/ + * + * John Heffner + */ + +#include +#include + +/* These factors derived from the recommended values in the aer: + * .01 and and 7/8. We use 50 instead of 100 to account for + * delayed ack. + */ +#define TCP_SCALABLE_AI_CNT 50U +#define TCP_SCALABLE_MD_SCALE 3 + +static void tcp_scalable_cong_avoid(struct sock *sk, u32 ack, u32 acked) +{ + struct tcp_sock *tp = tcp_sk(sk); + + if (!tcp_is_cwnd_limited(sk)) + return; + + if (tp->snd_cwnd <= tp->snd_ssthresh) + tcp_slow_start(tp, acked); + else + tcp_cong_avoid_ai(tp, min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT), + 1); +} + +static u32 tcp_scalable_ssthresh(struct sock *sk) +{ + const struct tcp_sock *tp = tcp_sk(sk); + + return max(tp->snd_cwnd - (tp->snd_cwnd>>TCP_SCALABLE_MD_SCALE), 2U); +} + +static struct tcp_congestion_ops tcp_scalable __read_mostly = { + .ssthresh = tcp_scalable_ssthresh, + .cong_avoid = tcp_scalable_cong_avoid, + + .owner = THIS_MODULE, + .name = "scalable", +}; + +static int __init tcp_scalable_register(void) +{ + return tcp_register_congestion_control(&tcp_scalable); +} + +static void __exit tcp_scalable_unregister(void) +{ + tcp_unregister_congestion_control(&tcp_scalable); +} + +module_init(tcp_scalable_register); +module_exit(tcp_scalable_unregister); + +MODULE_AUTHOR("John Heffner"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Scalable TCP"); -- cgit v1.2.3-54-g00ecf