diff options
Diffstat (limited to 'net/ipv4/tcp_veno.c')
| -rw-r--r-- | net/ipv4/tcp_veno.c | 51 |
1 files changed, 27 insertions, 24 deletions
diff --git a/net/ipv4/tcp_veno.c b/net/ipv4/tcp_veno.c index ce57bf302f6..27b9825753d 100644 --- a/net/ipv4/tcp_veno.c +++ b/net/ipv4/tcp_veno.c @@ -6,7 +6,7 @@ * "TCP Veno: TCP Enhancement for Transmission over Wireless Access Networks." * IEEE Journal on Selected Areas in Communication, * Feb. 2003. - * See http://www.ntu.edu.sg/home5/ZHOU0022/papers/CPFu03a.pdf + * See http://www.ie.cuhk.edu.hk/fileadmin/staff_upload/soung/Journal/J3.pdf */ #include <linux/mm.h> @@ -69,10 +69,16 @@ static void tcp_veno_init(struct sock *sk) } /* Do rtt sampling needed for Veno. */ -static void tcp_veno_rtt_calc(struct sock *sk, u32 usrtt) +static void tcp_veno_pkts_acked(struct sock *sk, u32 cnt, s32 rtt_us) { struct veno *veno = inet_csk_ca(sk); - u32 vrtt = usrtt + 1; /* Never allow zero rtt or basertt */ + u32 vrtt; + + if (rtt_us < 0) + return; + + /* Never allow zero rtt or baseRTT */ + vrtt = rtt_us + 1; /* Filter to find propagation delay: */ if (vrtt < veno->basertt) @@ -108,17 +114,18 @@ static void tcp_veno_cwnd_event(struct sock *sk, enum tcp_ca_event event) tcp_veno_init(sk); } -static void tcp_veno_cong_avoid(struct sock *sk, u32 ack, - u32 seq_rtt, u32 in_flight, int flag) +static void tcp_veno_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct veno *veno = inet_csk_ca(sk); - if (!veno->doing_veno_now) - return tcp_reno_cong_avoid(sk, ack, seq_rtt, in_flight, flag); + if (!veno->doing_veno_now) { + tcp_reno_cong_avoid(sk, ack, acked); + return; + } /* limited by applications */ - if (!tcp_is_cwnd_limited(sk, in_flight)) + if (!tcp_is_cwnd_limited(sk)) return; /* We do the Veno calculations only if we got enough rtt samples */ @@ -126,9 +133,10 @@ static void tcp_veno_cong_avoid(struct sock *sk, u32 ack, /* We don't have enough rtt samples to do the Veno * calculation, so we'll behave like Reno. */ - tcp_reno_cong_avoid(sk, ack, seq_rtt, in_flight, flag); + tcp_reno_cong_avoid(sk, ack, acked); } else { - u32 rtt, target_cwnd; + u64 target_cwnd; + u32 rtt; /* We have enough rtt samples, so, using the Veno * algorithm, we determine the state of the network. @@ -136,34 +144,29 @@ static void tcp_veno_cong_avoid(struct sock *sk, u32 ack, rtt = veno->minrtt; - target_cwnd = ((tp->snd_cwnd * veno->basertt) - << V_PARAM_SHIFT) / rtt; + target_cwnd = (tp->snd_cwnd * veno->basertt); + target_cwnd <<= V_PARAM_SHIFT; + do_div(target_cwnd, rtt); veno->diff = (tp->snd_cwnd << V_PARAM_SHIFT) - target_cwnd; if (tp->snd_cwnd <= tp->snd_ssthresh) { /* Slow start. */ - tcp_slow_start(tp); + tcp_slow_start(tp, acked); } else { /* Congestion avoidance. */ if (veno->diff < beta) { /* In the "non-congestive state", increase cwnd * every rtt. */ - if (tp->snd_cwnd_cnt >= tp->snd_cwnd) { - if (tp->snd_cwnd < tp->snd_cwnd_clamp) - tp->snd_cwnd++; - tp->snd_cwnd_cnt = 0; - } else - tp->snd_cwnd_cnt++; + tcp_cong_avoid_ai(tp, tp->snd_cwnd); } else { /* In the "congestive state", increase cwnd * every other rtt. */ if (tp->snd_cwnd_cnt >= tp->snd_cwnd) { - if (veno->inc - && tp->snd_cwnd < - tp->snd_cwnd_clamp) { + if (veno->inc && + tp->snd_cwnd < tp->snd_cwnd_clamp) { tp->snd_cwnd++; veno->inc = 0; } else @@ -198,11 +201,11 @@ static u32 tcp_veno_ssthresh(struct sock *sk) return max(tp->snd_cwnd >> 1U, 2U); } -static struct tcp_congestion_ops tcp_veno = { +static struct tcp_congestion_ops tcp_veno __read_mostly = { .init = tcp_veno_init, .ssthresh = tcp_veno_ssthresh, .cong_avoid = tcp_veno_cong_avoid, - .rtt_sample = tcp_veno_rtt_calc, + .pkts_acked = tcp_veno_pkts_acked, .set_state = tcp_veno_state, .cwnd_event = tcp_veno_cwnd_event, |