X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fipv4%2Ftcp_vegas.c;h=14504dada1166d57f36f3f603c5fbe5fbd0bfc95;hb=1481b9109fe771ec8b035d7760f42e36d2bed5d4;hp=b49dedcda52df949c159db5b12635c9414a1538a;hpb=c21723edd5f6c288ab613ed658b7140e07fc7209;p=linux-2.6

diff --git a/net/ipv4/tcp_vegas.c b/net/ipv4/tcp_vegas.c
index b49dedcda5..14504dada1 100644
--- a/net/ipv4/tcp_vegas.c
+++ b/net/ipv4/tcp_vegas.c
@@ -162,14 +162,15 @@ void tcp_vegas_cwnd_event(struct sock *sk, enum tcp_ca_event event)
 }
 EXPORT_SYMBOL_GPL(tcp_vegas_cwnd_event);
 
-static void tcp_vegas_cong_avoid(struct sock *sk, u32 ack,
-				 u32 in_flight, int flag)
+static void tcp_vegas_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct vegas *vegas = inet_csk_ca(sk);
 
-	if (!vegas->doing_vegas_now)
-		return tcp_reno_cong_avoid(sk, ack, in_flight, flag);
+	if (!vegas->doing_vegas_now) {
+		tcp_reno_cong_avoid(sk, ack, in_flight);
+		return;
+	}
 
 	/* The key players are v_beg_snd_una and v_beg_snd_nxt.
 	 *
@@ -228,9 +229,10 @@ static void tcp_vegas_cong_avoid(struct sock *sk, u32 ack,
 			/* We don't have enough RTT samples to do the Vegas
 			 * calculation, so we'll behave like Reno.
 			 */
-			tcp_reno_cong_avoid(sk, ack, in_flight, flag);
+			tcp_reno_cong_avoid(sk, ack, in_flight);
 		} else {
-			u32 rtt, target_cwnd, diff;
+			u32 rtt, diff;
+			u64 target_cwnd;
 
 			/* We have enough RTT samples, so, using the Vegas
 			 * algorithm, we determine if we should increase or
@@ -253,8 +255,9 @@ static void tcp_vegas_cong_avoid(struct sock *sk, u32 ack,
 			 * We keep it as a fixed point number with
 			 * V_PARAM_SHIFT bits to the right of the binary point.
 			 */
-			target_cwnd = ((old_wnd * vegas->baseRTT)
-				       << V_PARAM_SHIFT) / rtt;
+			target_cwnd = ((u64)old_wnd * vegas->baseRTT);
+			target_cwnd <<= V_PARAM_SHIFT;
+			do_div(target_cwnd, rtt);
 
 			/* Calculate the difference between the window we had,
 			 * and the window we would like to have. This quantity
@@ -266,26 +269,25 @@ static void tcp_vegas_cong_avoid(struct sock *sk, u32 ack,
 			 */
 			diff = (old_wnd << V_PARAM_SHIFT) - target_cwnd;
 
-			if (tp->snd_cwnd <= tp->snd_ssthresh) {
-				/* Slow start.  */
-				if (diff > gamma) {
-					/* Going too fast. Time to slow down
-					 * and switch to congestion avoidance.
-					 */
-					tp->snd_ssthresh = 2;
-
-					/* Set cwnd to match the actual rate
-					 * exactly:
-					 *   cwnd = (actual rate) * baseRTT
-					 * Then we add 1 because the integer
-					 * truncation robs us of full link
-					 * utilization.
-					 */
-					tp->snd_cwnd = min(tp->snd_cwnd,
-							   (target_cwnd >>
-							    V_PARAM_SHIFT)+1);
+			if (diff > gamma && tp->snd_ssthresh > 2 ) {
+				/* Going too fast. Time to slow down
+				 * and switch to congestion avoidance.
+				 */
+				tp->snd_ssthresh = 2;
+
+				/* Set cwnd to match the actual rate
+				 * exactly:
+				 *   cwnd = (actual rate) * baseRTT
+				 * Then we add 1 because the integer
+				 * truncation robs us of full link
+				 * utilization.
+				 */
+				tp->snd_cwnd = min(tp->snd_cwnd,
+						   ((u32)target_cwnd >>
+						    V_PARAM_SHIFT)+1);
 
-				}
+			} else if (tp->snd_cwnd <= tp->snd_ssthresh) {
+				/* Slow start.  */
 				tcp_slow_start(tp);
 			} else {
 				/* Congestion avoidance. */