From 7752237e9f07b316f81aebdc43f0d7c9a4ba0acf Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Mon, 23 Apr 2007 22:28:23 -0700 Subject: [TCP] TCP YEAH: Use vegas dont copy it. Rather than using a copy of vegas code, the YEAH code should just have it exported so there is common code. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/ipv4/tcp_yeah.c | 53 ++++++++++++++++++++++++----------------------------- 1 file changed, 24 insertions(+), 29 deletions(-) (limited to 'net/ipv4/tcp_yeah.c') diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c index 81ef02c1649a..545ed237ab53 100644 --- a/net/ipv4/tcp_yeah.c +++ b/net/ipv4/tcp_yeah.c @@ -6,13 +6,14 @@ * http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf * */ +#include +#include +#include +#include -#include "tcp_yeah.h" +#include -/* 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 @@ -26,14 +27,7 @@ /* 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; @@ -84,9 +78,10 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, if (!tcp_is_cwnd_limited(sk, in_flight)) return; - if (tp->snd_cwnd <= tp->snd_ssthresh) { + if (tp->snd_cwnd <= tp->snd_ssthresh) tcp_slow_start(tp); - } else if (!yeah->doing_reno_now) { + + else if (!yeah->doing_reno_now) { /* Scalable */ tp->snd_cwnd_cnt+=yeah->pkts_acked; @@ -110,19 +105,19 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, } } - /* 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. * @@ -132,7 +127,7 @@ 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 @@ -143,7 +138,7 @@ 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; @@ -158,18 +153,18 @@ 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)) { + 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 , @@ -208,13 +203,13 @@ 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; } } -- cgit v1.2.3-59-g8ed1b