diff options
Diffstat (limited to 'net/ipv4/tcp_bic.c')
| -rw-r--r-- | net/ipv4/tcp_bic.c | 63 |
1 files changed, 25 insertions, 38 deletions
diff --git a/net/ipv4/tcp_bic.c b/net/ipv4/tcp_bic.c index f45e1c242440..58358bf92e1b 100644 --- a/net/ipv4/tcp_bic.c +++ b/net/ipv4/tcp_bic.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Binary Increase Congestion control for TCP * Home page: @@ -17,7 +18,6 @@ #include <linux/module.h> #include <net/tcp.h> - #define BICTCP_BETA_SCALE 1024 /* Scale factor beta calculation * max_cwnd = snd_cwnd * beta */ @@ -46,12 +46,10 @@ MODULE_PARM_DESC(initial_ssthresh, "initial value of slow start threshold"); module_param(smooth_part, int, 0644); MODULE_PARM_DESC(smooth_part, "log(B/(B*Smin))/log(B/(B-1))+B, # of RTT from Wmax-B to Wmax"); - /* BIC TCP Parameters */ struct bictcp { u32 cnt; /* increase cwnd by 1 after ACKs */ - u32 last_max_cwnd; /* last maximum snd_cwnd */ - u32 loss_cwnd; /* congestion window at last loss */ + u32 last_max_cwnd; /* last maximum snd_cwnd */ u32 last_cwnd; /* the last snd_cwnd */ u32 last_time; /* time when updated last_cwnd */ u32 epoch_start; /* beginning of an epoch */ @@ -74,7 +72,6 @@ static void bictcp_init(struct sock *sk) struct bictcp *ca = inet_csk_ca(sk); bictcp_reset(ca); - ca->loss_cwnd = 0; if (initial_ssthresh) tcp_sk(sk)->snd_ssthresh = initial_ssthresh; @@ -86,14 +83,14 @@ static void bictcp_init(struct sock *sk) static inline void bictcp_update(struct bictcp *ca, u32 cwnd) { if (ca->last_cwnd == cwnd && - (s32)(tcp_time_stamp - ca->last_time) <= HZ / 32) + (s32)(tcp_jiffies32 - ca->last_time) <= HZ / 32) return; ca->last_cwnd = cwnd; - ca->last_time = tcp_time_stamp; + ca->last_time = tcp_jiffies32; if (ca->epoch_start == 0) /* record the beginning of an epoch */ - ca->epoch_start = tcp_time_stamp; + ca->epoch_start = tcp_jiffies32; /* start off normal */ if (cwnd <= low_window) { @@ -103,7 +100,7 @@ static inline void bictcp_update(struct bictcp *ca, u32 cwnd) /* binary increase */ if (cwnd < ca->last_max_cwnd) { - __u32 dist = (ca->last_max_cwnd - cwnd) + __u32 dist = (ca->last_max_cwnd - cwnd) / BICTCP_B; if (dist > max_increment) @@ -140,21 +137,21 @@ static inline void bictcp_update(struct bictcp *ca, u32 cwnd) ca->cnt = 1; } -static void bictcp_cong_avoid(struct sock *sk, u32 ack, u32 in_flight) +static void bictcp_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); - if (!tcp_is_cwnd_limited(sk, in_flight)) + if (!tcp_is_cwnd_limited(sk)) return; - if (tp->snd_cwnd <= tp->snd_ssthresh) - tcp_slow_start(tp); - else { - bictcp_update(ca, tp->snd_cwnd); - tcp_cong_avoid_ai(tp, ca->cnt); + if (tcp_in_slow_start(tp)) { + acked = tcp_slow_start(tp, acked); + if (!acked) + return; } - + bictcp_update(ca, tcp_snd_cwnd(tp)); + tcp_cong_avoid_ai(tp, ca->cnt, acked); } /* @@ -169,26 +166,16 @@ static u32 bictcp_recalc_ssthresh(struct sock *sk) ca->epoch_start = 0; /* end of epoch */ /* Wmax and fast convergence */ - if (tp->snd_cwnd < ca->last_max_cwnd && fast_convergence) - ca->last_max_cwnd = (tp->snd_cwnd * (BICTCP_BETA_SCALE + beta)) + if (tcp_snd_cwnd(tp) < ca->last_max_cwnd && fast_convergence) + ca->last_max_cwnd = (tcp_snd_cwnd(tp) * (BICTCP_BETA_SCALE + beta)) / (2 * BICTCP_BETA_SCALE); else - ca->last_max_cwnd = tp->snd_cwnd; + ca->last_max_cwnd = tcp_snd_cwnd(tp); - ca->loss_cwnd = tp->snd_cwnd; - - - if (tp->snd_cwnd <= low_window) - return max(tp->snd_cwnd >> 1U, 2U); + if (tcp_snd_cwnd(tp) <= low_window) + return max(tcp_snd_cwnd(tp) >> 1U, 2U); else - return max((tp->snd_cwnd * beta) / BICTCP_BETA_SCALE, 2U); -} - -static u32 bictcp_undo_cwnd(struct sock *sk) -{ - const struct tcp_sock *tp = tcp_sk(sk); - const struct bictcp *ca = inet_csk_ca(sk); - return max(tp->snd_cwnd, ca->loss_cwnd); + return max((tcp_snd_cwnd(tp) * beta) / BICTCP_BETA_SCALE, 2U); } static void bictcp_state(struct sock *sk, u8 new_state) @@ -200,24 +187,24 @@ static void bictcp_state(struct sock *sk, u8 new_state) /* Track delayed acknowledgment ratio using sliding window * ratio = (15*ratio + sample) / 16 */ -static void bictcp_acked(struct sock *sk, u32 cnt, s32 rtt) +static void bictcp_acked(struct sock *sk, const struct ack_sample *sample) { const struct inet_connection_sock *icsk = inet_csk(sk); if (icsk->icsk_ca_state == TCP_CA_Open) { struct bictcp *ca = inet_csk_ca(sk); - cnt -= ca->delayed_ack >> ACK_RATIO_SHIFT; - ca->delayed_ack += cnt; + + ca->delayed_ack += sample->pkts_acked - + (ca->delayed_ack >> ACK_RATIO_SHIFT); } } - static struct tcp_congestion_ops bictcp __read_mostly = { .init = bictcp_init, .ssthresh = bictcp_recalc_ssthresh, .cong_avoid = bictcp_cong_avoid, .set_state = bictcp_state, - .undo_cwnd = bictcp_undo_cwnd, + .undo_cwnd = tcp_reno_undo_cwnd, .pkts_acked = bictcp_acked, .owner = THIS_MODULE, .name = "bic", |
