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Diffstat (limited to 'net/ipv4/tcp_lp.c')
-rw-r--r--net/ipv4/tcp_lp.c59
1 files changed, 36 insertions, 23 deletions
diff --git a/net/ipv4/tcp_lp.c b/net/ipv4/tcp_lp.c
index 72f7218b03f5..976b56644a8a 100644
--- a/net/ipv4/tcp_lp.c
+++ b/net/ipv4/tcp_lp.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* TCP Low Priority (TCP-LP)
*
@@ -22,9 +23,9 @@
* Original Author:
* Aleksandar Kuzmanovic <akuzma@northwestern.edu>
* Available from:
- * http://www.ece.rice.edu/~akuzma/Doc/akuzma/TCP-LP.pdf
+ * https://users.cs.northwestern.edu/~akuzma/doc/TCP-LP-ToN.pdf
* Original implementation for 2.4.19:
- * http://www-ece.rice.edu/networks/TCP-LP/
+ * https://users.cs.northwestern.edu/~akuzma/rice/TCP-LP/linux/tcp-lp-linux.htm
*
* 2.6.x module Authors:
* Wong Hoi Sing, Edison <hswong3i@gmail.com>
@@ -37,7 +38,7 @@
#include <net/tcp.h>
/* resolution of owd */
-#define LP_RESOL 1000
+#define LP_RESOL TCP_TS_HZ
/**
* enum tcp_lp_state
@@ -62,7 +63,7 @@ enum tcp_lp_state {
* @sowd: smoothed OWD << 3
* @owd_min: min OWD
* @owd_max: max OWD
- * @owd_max_rsv: resrved max owd
+ * @owd_max_rsv: reserved max owd
* @remote_hz: estimated remote HZ
* @remote_ref_time: remote reference time
* @local_ref_time: local reference time
@@ -88,6 +89,7 @@ struct lp {
/**
* tcp_lp_init
+ * @sk: socket to initialize congestion control algorithm for
*
* Init all required variables.
* Clone the handling from Vegas module implementation.
@@ -110,21 +112,25 @@ static void tcp_lp_init(struct sock *sk)
/**
* tcp_lp_cong_avoid
+ * @sk: socket to avoid congesting
+ * @ack: current ack sequence number
+ * @acked: number of ACKed packets
*
* Implementation of cong_avoid.
* 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 in_flight)
+static void tcp_lp_cong_avoid(struct sock *sk, u32 ack, u32 acked)
{
struct lp *lp = inet_csk_ca(sk);
if (!(lp->flag & LP_WITHIN_INF))
- tcp_reno_cong_avoid(sk, ack, in_flight);
+ tcp_reno_cong_avoid(sk, ack, acked);
}
/**
* tcp_lp_remote_hz_estimator
+ * @sk: socket which needs an estimate for the remote HZs
*
* Estimate remote HZ.
* We keep on updating the estimated value, where original TCP-LP
@@ -147,9 +153,9 @@ static u32 tcp_lp_remote_hz_estimator(struct sock *sk)
tp->rx_opt.rcv_tsecr == lp->local_ref_time)
goto out;
- m = HZ * (tp->rx_opt.rcv_tsval -
- lp->remote_ref_time) / (tp->rx_opt.rcv_tsecr -
- lp->local_ref_time);
+ m = TCP_TS_HZ *
+ (tp->rx_opt.rcv_tsval - lp->remote_ref_time) /
+ (tp->rx_opt.rcv_tsecr - lp->local_ref_time);
if (m < 0)
m = -m;
@@ -175,6 +181,7 @@ static u32 tcp_lp_remote_hz_estimator(struct sock *sk)
/**
* tcp_lp_owd_calculator
+ * @sk: socket to calculate one way delay for
*
* Calculate one way delay (in relative format).
* Original implement OWD as minus of remote time difference to local time
@@ -194,7 +201,7 @@ static u32 tcp_lp_owd_calculator(struct sock *sk)
if (lp->flag & LP_VALID_RHZ) {
owd =
tp->rx_opt.rcv_tsval * (LP_RESOL / lp->remote_hz) -
- tp->rx_opt.rcv_tsecr * (LP_RESOL / HZ);
+ tp->rx_opt.rcv_tsecr * (LP_RESOL / TCP_TS_HZ);
if (owd < 0)
owd = -owd;
}
@@ -209,6 +216,8 @@ static u32 tcp_lp_owd_calculator(struct sock *sk)
/**
* tcp_lp_rtt_sample
+ * @sk: socket to add a rtt sample to
+ * @rtt: round trip time, which is ignored!
*
* Implementation or rtt_sample.
* Will take the following action,
@@ -253,6 +262,8 @@ static void tcp_lp_rtt_sample(struct sock *sk, u32 rtt)
/**
* tcp_lp_pkts_acked
+ * @sk: socket requiring congestion avoidance calculations
+ * @sample: ACK sample containing timing and rate information
*
* Implementation of pkts_acked.
* Deal with active drop under Early Congestion Indication.
@@ -260,20 +271,23 @@ static void tcp_lp_rtt_sample(struct sock *sk, u32 rtt)
* 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, s32 rtt_us)
+static void tcp_lp_pkts_acked(struct sock *sk, const struct ack_sample *sample)
{
struct tcp_sock *tp = tcp_sk(sk);
struct lp *lp = inet_csk_ca(sk);
+ u32 now = tcp_time_stamp_ts(tp);
+ u32 delta;
- if (rtt_us > 0)
- tcp_lp_rtt_sample(sk, rtt_us);
+ if (sample->rtt_us > 0)
+ tcp_lp_rtt_sample(sk, sample->rtt_us);
/* calc inference */
- if (tcp_time_stamp > tp->rx_opt.rcv_tsecr)
- lp->inference = 3 * (tcp_time_stamp - tp->rx_opt.rcv_tsecr);
+ delta = now - tp->rx_opt.rcv_tsecr;
+ if ((s32)delta > 0)
+ lp->inference = 3 * delta;
/* test if within inference */
- if (lp->last_drop && (tcp_time_stamp - lp->last_drop < lp->inference))
+ if (lp->last_drop && (now - lp->last_drop < lp->inference))
lp->flag |= LP_WITHIN_INF;
else
lp->flag &= ~LP_WITHIN_INF;
@@ -286,7 +300,7 @@ static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked, s32 rtt_us)
lp->flag &= ~LP_WITHIN_THR;
pr_debug("TCP-LP: %05o|%5u|%5u|%15u|%15u|%15u\n", lp->flag,
- tp->snd_cwnd, lp->remote_hz, lp->owd_min, lp->owd_max,
+ tcp_snd_cwnd(tp), lp->remote_hz, lp->owd_min, lp->owd_max,
lp->sowd >> 3);
if (lp->flag & LP_WITHIN_THR)
@@ -294,7 +308,7 @@ static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked, s32 rtt_us)
/* FIXME: try to reset owd_min and owd_max here
* so decrease the chance the min/max is no longer suitable
- * and will usually within threshold when whithin inference */
+ * and will usually within threshold when within inference */
lp->owd_min = lp->sowd >> 3;
lp->owd_max = lp->sowd >> 2;
lp->owd_max_rsv = lp->sowd >> 2;
@@ -302,23 +316,22 @@ static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked, s32 rtt_us)
/* happened within inference
* drop snd_cwnd into 1 */
if (lp->flag & LP_WITHIN_INF)
- tp->snd_cwnd = 1U;
+ tcp_snd_cwnd_set(tp, 1U);
/* happened after inference
* cut snd_cwnd into half */
else
- tp->snd_cwnd = max(tp->snd_cwnd >> 1U, 1U);
+ tcp_snd_cwnd_set(tp, max(tcp_snd_cwnd(tp) >> 1U, 1U));
/* record this drop time */
- lp->last_drop = tcp_time_stamp;
+ lp->last_drop = now;
}
static struct tcp_congestion_ops tcp_lp __read_mostly = {
- .flags = TCP_CONG_RTT_STAMP,
.init = tcp_lp_init,
.ssthresh = tcp_reno_ssthresh,
+ .undo_cwnd = tcp_reno_undo_cwnd,
.cong_avoid = tcp_lp_cong_avoid,
- .min_cwnd = tcp_reno_min_cwnd,
.pkts_acked = tcp_lp_pkts_acked,
.owner = THIS_MODULE,
generated by cgit (git 2.34.1) at 2025-12-21 21:13:30 +0000