diff options
Diffstat (limited to 'net/ipv4/tcp_yeah.c')
| -rw-r--r-- | net/ipv4/tcp_yeah.c | 105 |
1 files changed, 46 insertions, 59 deletions
diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c index 46dd1bee583..599b79b8eac 100644 --- a/net/ipv4/tcp_yeah.c +++ b/net/ipv4/tcp_yeah.c @@ -3,37 +3,31 @@ * YeAH TCP * * For further details look at: - * http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf + * https://web.archive.org/web/20080316215752/http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf * */ +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/skbuff.h> +#include <linux/inet_diag.h> -#include "tcp_yeah.h" +#include <net/tcp.h> -/* Default values of the Vegas variables, in fixed-point representation - * with V_PARAM_SHIFT bits to the right of the binary point. - */ -#define V_PARAM_SHIFT 1 +#include "tcp_vegas.h" -#define TCP_YEAH_ALPHA 80 //lin number of packets queued at the bottleneck -#define TCP_YEAH_GAMMA 1 //lin fraction of queue to be removed per rtt -#define TCP_YEAH_DELTA 3 //log minimum fraction of cwnd to be removed on loss -#define TCP_YEAH_EPSILON 1 //log maximum fraction to be removed on early decongestion -#define TCP_YEAH_PHY 8 //lin maximum delta from base -#define TCP_YEAH_RHO 16 //lin minumum number of consecutive rtt to consider competition on loss -#define TCP_YEAH_ZETA 50 //lin minimum number of state switchs to reset reno_count +#define TCP_YEAH_ALPHA 80 /* number of packets queued at the bottleneck */ +#define TCP_YEAH_GAMMA 1 /* fraction of queue to be removed per rtt */ +#define TCP_YEAH_DELTA 3 /* log minimum fraction of cwnd to be removed on loss */ +#define TCP_YEAH_EPSILON 1 /* log maximum fraction to be removed on early decongestion */ +#define TCP_YEAH_PHY 8 /* maximum delta from base */ +#define TCP_YEAH_RHO 16 /* minimum number of consecutive rtt to consider competition on loss */ +#define TCP_YEAH_ZETA 50 /* minimum number of state switches to reset reno_count */ #define TCP_SCALABLE_AI_CNT 100U /* YeAH variables */ struct yeah { - /* Vegas */ - u32 beg_snd_nxt; /* right edge during last RTT */ - u32 beg_snd_una; /* left edge during last RTT */ - u32 beg_snd_cwnd; /* saves the size of the cwnd */ - u8 doing_vegas_now;/* if true, do vegas for this RTT */ - u16 cntRTT; /* # of RTTs measured within last RTT */ - u32 minRTT; /* min of RTTs measured within last RTT (in usec) */ - u32 baseRTT; /* the min of all Vegas RTT measurements seen (in usec) */ + struct vegas vegas; /* must be first */ /* YeAH */ u32 lastQ; @@ -64,30 +58,32 @@ static void tcp_yeah_init(struct sock *sk) } -static void tcp_yeah_pkts_acked(struct sock *sk, u32 pkts_acked) +static void tcp_yeah_pkts_acked(struct sock *sk, u32 pkts_acked, s32 rtt_us) { const struct inet_connection_sock *icsk = inet_csk(sk); struct yeah *yeah = inet_csk_ca(sk); if (icsk->icsk_ca_state == TCP_CA_Open) yeah->pkts_acked = pkts_acked; + + tcp_vegas_pkts_acked(sk, pkts_acked, rtt_us); } -static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, - u32 seq_rtt, u32 in_flight, int flag) +static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); struct yeah *yeah = 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 if (!yeah->doing_reno_now) { + if (tp->snd_cwnd <= tp->snd_ssthresh) + tcp_slow_start(tp, acked); + + else if (!yeah->doing_reno_now) { /* Scalable */ - tp->snd_cwnd_cnt+=yeah->pkts_acked; + tp->snd_cwnd_cnt += yeah->pkts_acked; if (tp->snd_cwnd_cnt > min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT)){ if (tp->snd_cwnd < tp->snd_cwnd_clamp) tp->snd_cwnd++; @@ -98,29 +94,22 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, } else { /* Reno */ - - if (tp->snd_cwnd_cnt < tp->snd_cwnd) - tp->snd_cwnd_cnt++; - - if (tp->snd_cwnd_cnt >= tp->snd_cwnd) { - tp->snd_cwnd++; - tp->snd_cwnd_cnt = 0; - } + tcp_cong_avoid_ai(tp, tp->snd_cwnd); } - /* The key players are v_beg_snd_una and v_beg_snd_nxt. + /* The key players are v_vegas.beg_snd_una and v_beg_snd_nxt. * * These are so named because they represent the approximate values * of snd_una and snd_nxt at the beginning of the current RTT. More * precisely, they represent the amount of data sent during the RTT. * At the end of the RTT, when we receive an ACK for v_beg_snd_nxt, - * we will calculate that (v_beg_snd_nxt - v_beg_snd_una) outstanding + * we will calculate that (v_beg_snd_nxt - v_vegas.beg_snd_una) outstanding * bytes of data have been ACKed during the course of the RTT, giving * an "actual" rate of: * - * (v_beg_snd_nxt - v_beg_snd_una) / (rtt duration) + * (v_beg_snd_nxt - v_vegas.beg_snd_una) / (rtt duration) * - * Unfortunately, v_beg_snd_una is not exactly equal to snd_una, + * Unfortunately, v_vegas.beg_snd_una is not exactly equal to snd_una, * because delayed ACKs can cover more than one segment, so they * don't line up yeahly with the boundaries of RTTs. * @@ -130,7 +119,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, * So we keep track of our cwnd separately, in v_beg_snd_cwnd. */ - if (after(ack, yeah->beg_snd_nxt)) { + if (after(ack, yeah->vegas.beg_snd_nxt)) { /* We do the Vegas calculations only if we got enough RTT * samples that we can be reasonably sure that we got @@ -141,7 +130,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, * If we have 3 samples, we should be OK. */ - if (yeah->cntRTT > 2) { + if (yeah->vegas.cntRTT > 2) { u32 rtt, queue; u64 bw; @@ -156,20 +145,20 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, * of delayed ACKs, at the cost of noticing congestion * a bit later. */ - rtt = yeah->minRTT; + rtt = yeah->vegas.minRTT; /* Compute excess number of packets above bandwidth * Avoid doing full 64 bit divide. */ bw = tp->snd_cwnd; - bw *= rtt - yeah->baseRTT; + bw *= rtt - yeah->vegas.baseRTT; do_div(bw, rtt); queue = bw; if (queue > TCP_YEAH_ALPHA || - rtt - yeah->baseRTT > (yeah->baseRTT / TCP_YEAH_PHY)) { - if (queue > TCP_YEAH_ALPHA - && tp->snd_cwnd > yeah->reno_count) { + rtt - yeah->vegas.baseRTT > (yeah->vegas.baseRTT / TCP_YEAH_PHY)) { + if (queue > TCP_YEAH_ALPHA && + tp->snd_cwnd > yeah->reno_count) { u32 reduction = min(queue / TCP_YEAH_GAMMA , tp->snd_cwnd >> TCP_YEAH_EPSILON); @@ -206,13 +195,13 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, /* Save the extent of the current window so we can use this * at the end of the next RTT. */ - yeah->beg_snd_una = yeah->beg_snd_nxt; - yeah->beg_snd_nxt = tp->snd_nxt; - yeah->beg_snd_cwnd = tp->snd_cwnd; + yeah->vegas.beg_snd_una = yeah->vegas.beg_snd_nxt; + yeah->vegas.beg_snd_nxt = tp->snd_nxt; + yeah->vegas.beg_snd_cwnd = tp->snd_cwnd; /* Wipe the slate clean for the next RTT. */ - yeah->cntRTT = 0; - yeah->minRTT = 0x7fffffff; + yeah->vegas.cntRTT = 0; + yeah->vegas.minRTT = 0x7fffffff; } } @@ -224,11 +213,11 @@ static u32 tcp_yeah_ssthresh(struct sock *sk) { if (yeah->doing_reno_now < TCP_YEAH_RHO) { reduction = yeah->lastQ; - reduction = min( reduction, max(tp->snd_cwnd>>1, 2U) ); + reduction = min(reduction, max(tp->snd_cwnd>>1, 2U)); - reduction = max( reduction, tp->snd_cwnd >> TCP_YEAH_DELTA); + reduction = max(reduction, tp->snd_cwnd >> TCP_YEAH_DELTA); } else - reduction = max(tp->snd_cwnd>>1,2U); + reduction = max(tp->snd_cwnd>>1, 2U); yeah->fast_count = 0; yeah->reno_count = max(yeah->reno_count>>1, 2U); @@ -236,12 +225,10 @@ static u32 tcp_yeah_ssthresh(struct sock *sk) { return tp->snd_cwnd - reduction; } -static struct tcp_congestion_ops tcp_yeah = { +static struct tcp_congestion_ops tcp_yeah __read_mostly = { .init = tcp_yeah_init, .ssthresh = tcp_yeah_ssthresh, .cong_avoid = tcp_yeah_cong_avoid, - .min_cwnd = tcp_reno_min_cwnd, - .rtt_sample = tcp_vegas_rtt_calc, .set_state = tcp_vegas_state, .cwnd_event = tcp_vegas_cwnd_event, .get_info = tcp_vegas_get_info, |
