net/ipv4/tcp_bic.c

60 static inline void bictcp_reset(struct bictcp *ca)
62 	ca->cnt = 0;
63 	ca->last_max_cwnd = 0;
64 	ca->last_cwnd = 0;
65 	ca->last_time = 0;
66 	ca->epoch_start = 0;
67 	ca->delayed_ack = 2 << ACK_RATIO_SHIFT;
72 	struct bictcp *ca = inet_csk_ca(sk);
74 	bictcp_reset(ca);
83 static inline void bictcp_update(struct bictcp *ca, u32 cwnd)
85 	if (ca->last_cwnd == cwnd &&
86 	    (s32)(tcp_jiffies32 - ca->last_time) <= HZ / 32)
89 	ca->last_cwnd = cwnd;
90 	ca->last_time = tcp_jiffies32;
92 	if (ca->epoch_start == 0) /* record the beginning of an epoch */
93 		ca->epoch_start = tcp_jiffies32;
97 		ca->cnt = cwnd;
102 	if (cwnd < ca->last_max_cwnd) {
103 		__u32	dist = (ca->last_max_cwnd - cwnd)
108 			ca->cnt = cwnd / max_increment;
111 			ca->cnt = (cwnd * smooth_part) / BICTCP_B;
114 			ca->cnt = cwnd / dist;
117 		if (cwnd < ca->last_max_cwnd + BICTCP_B)
119 			ca->cnt = (cwnd * smooth_part) / BICTCP_B;
120 		else if (cwnd < ca->last_max_cwnd + max_increment*(BICTCP_B-1))
122 			ca->cnt = (cwnd * (BICTCP_B-1))
123 				/ (cwnd - ca->last_max_cwnd);
126 			ca->cnt = cwnd / max_increment;
130 	if (ca->last_max_cwnd == 0) {
131 		if (ca->cnt > 20) /* increase cwnd 5% per RTT */
132 			ca->cnt = 20;
135 	ca->cnt = (ca->cnt << ACK_RATIO_SHIFT) / ca->delayed_ack;
136 	if (ca->cnt == 0)			/* cannot be zero */
137 		ca->cnt = 1;
143 	struct bictcp *ca = inet_csk_ca(sk);
153 	bictcp_update(ca, tcp_snd_cwnd(tp));
154 	tcp_cong_avoid_ai(tp, ca->cnt, acked);
164 	struct bictcp *ca = inet_csk_ca(sk);
166 	ca->epoch_start = 0;	/* end of epoch */
169 	if (tcp_snd_cwnd(tp) < ca->last_max_cwnd && fast_convergence)
170 		ca->last_max_cwnd = (tcp_snd_cwnd(tp) * (BICTCP_BETA_SCALE + beta))
173 		ca->last_max_cwnd = tcp_snd_cwnd(tp);
195 		struct bictcp *ca = inet_csk_ca(sk);
197 		ca->delayed_ack += sample->pkts_acked -
198 			(ca->delayed_ack >> ACK_RATIO_SHIFT);