*
* TCP Low Priority is a distributed algorithm whose goal is to utilize only
* the excess network bandwidth as compared to the ``fair share`` of
- * bandwidth as targeted by TCP. Available from:
- * http://www.ece.rice.edu/~akuzma/Doc/akuzma/TCP-LP.pdf
+ * bandwidth as targeted by TCP.
*
- * Original Author:
- * Aleksandar Kuzmanovic <akuzma@northwestern.edu>
- *
- * See http://www-ece.rice.edu/networks/TCP-LP/ for their implementation.
* As of 2.6.13, Linux supports pluggable congestion control algorithms.
* Due to the limitation of the API, we take the following changes from
* the original TCP-LP implementation:
* o OWD is handled in relative format, where local time stamp will in
* tcp_time_stamp format.
*
- * Port from 2.4.19 to 2.6.16 as module by:
- * Wong Hoi Sing Edison <hswong3i@gmail.com>
- * Hung Hing Lun <hlhung3i@gmail.com>
+ * Original Author:
+ * Aleksandar Kuzmanovic <akuzma@northwestern.edu>
+ * Available from:
+ * http://www.ece.rice.edu/~akuzma/Doc/akuzma/TCP-LP.pdf
+ * Original implementation for 2.4.19:
+ * http://www-ece.rice.edu/networks/TCP-LP/
*
- * Version: $Id: tcp_lp.c,v 1.22 2006-05-02 18:18:19 hswong3i Exp $
+ * 2.6.x module Authors:
+ * Wong Hoi Sing, Edison <hswong3i@gmail.com>
+ * Hung Hing Lun, Mike <hlhung3i@gmail.com>
+ * SourceForge project page:
+ * http://tcp-lp-mod.sourceforge.net/
*/
-#include <linux/config.h>
#include <linux/module.h>
#include <net/tcp.h>
* Will only call newReno CA when away from inference.
* From TCP-LP's paper, this will be handled in additive increasement.
*/
-static void tcp_lp_cong_avoid(struct sock *sk, u32 ack, u32 rtt, u32 in_flight,
- int flag)
+static void tcp_lp_cong_avoid(struct sock *sk, u32 ack, u32 in_flight, int flag)
{
struct lp *lp = inet_csk_ca(sk);
if (!(lp->flag & LP_WITHIN_INF))
- tcp_reno_cong_avoid(sk, ack, rtt, in_flight, flag);
+ tcp_reno_cong_avoid(sk, ack, in_flight, flag);
}
/**
if (m < 0)
m = -m;
- if (rhz != 0) {
+ if (rhz > 0) {
m -= rhz >> 6; /* m is now error in remote HZ est */
rhz += m; /* 63/64 old + 1/64 new */
} else
rhz = m << 6;
+ out:
/* record time for successful remote HZ calc */
- lp->flag |= LP_VALID_RHZ;
+ if ((rhz >> 6) > 0)
+ lp->flag |= LP_VALID_RHZ;
+ else
+ lp->flag &= ~LP_VALID_RHZ;
- out:
/* record reference time stamp */
lp->remote_ref_time = tp->rx_opt.rcv_tsval;
lp->local_ref_time = tp->rx_opt.rcv_tsecr;
* 3. calc smoothed OWD (SOWD).
* Most ideas come from the original TCP-LP implementation.
*/
-static void tcp_lp_rtt_sample(struct sock *sk, u32 usrtt)
+static void tcp_lp_rtt_sample(struct sock *sk, u32 rtt)
{
struct lp *lp = inet_csk_ca(sk);
s64 mowd = tcp_lp_owd_calculator(sk);
* newReno in increase case.
* We work it out by following the idea from TCP-LP's paper directly
*/
-static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked)
+static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked, ktime_t last)
{
struct tcp_sock *tp = tcp_sk(sk);
struct lp *lp = inet_csk_ca(sk);
+ if (!ktime_equal(last, net_invalid_timestamp()))
+ tcp_lp_rtt_sample(sk, ktime_to_us(net_timedelta(last)));
+
/* calc inference */
if (tcp_time_stamp > tp->rx_opt.rcv_tsecr)
lp->inference = 3 * (tcp_time_stamp - tp->rx_opt.rcv_tsecr);
}
static struct tcp_congestion_ops tcp_lp = {
+ .flags = TCP_CONG_RTT_STAMP,
.init = tcp_lp_init,
.ssthresh = tcp_reno_ssthresh,
.cong_avoid = tcp_lp_cong_avoid,
.min_cwnd = tcp_reno_min_cwnd,
- .rtt_sample = tcp_lp_rtt_sample,
.pkts_acked = tcp_lp_pkts_acked,
.owner = THIS_MODULE,
static int __init tcp_lp_register(void)
{
- BUG_ON(sizeof(struct lp) > ICSK_CA_PRIV_SIZE);
+ BUILD_BUG_ON(sizeof(struct lp) > ICSK_CA_PRIV_SIZE);
return tcp_register_congestion_control(&tcp_lp);
}
module_init(tcp_lp_register);
module_exit(tcp_lp_unregister);
-MODULE_AUTHOR("Wong Hoi Sing Edison, Hung Hing Lun");
+MODULE_AUTHOR("Wong Hoi Sing Edison, Hung Hing Lun Mike");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("TCP Low Priority");