From 03fba0479600114f32d29eee74ca3eaa364606bf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen@helsinki.fi>
Date: Thu, 3 May 2007 13:28:35 -0700
Subject: [PATCH] [TCP] Highspeed: Limited slow-start is nowadays in
 tcp_slow_start
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Reuse limited slow-start (RFC3742) included into tcp_cong instead
of having another implementation in High Speed TCP.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/ipv4/tcp_highspeed.c | 24 +++---------------------
 1 file changed, 3 insertions(+), 21 deletions(-)

diff --git a/net/ipv4/tcp_highspeed.c b/net/ipv4/tcp_highspeed.c
index a291097fcc0a..43d624e5043c 100644
--- a/net/ipv4/tcp_highspeed.c
+++ b/net/ipv4/tcp_highspeed.c
@@ -97,10 +97,6 @@ struct hstcp {
 	u32	ai;
 };
 
-static int max_ssthresh = 100;
-module_param(max_ssthresh, int, 0644);
-MODULE_PARM_DESC(max_ssthresh, "limited slow start threshold (RFC3742)");
-
 static void hstcp_init(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
@@ -122,23 +118,9 @@ static void hstcp_cong_avoid(struct sock *sk, u32 adk, u32 rtt,
 	if (!tcp_is_cwnd_limited(sk, in_flight))
 		return;
 
-	if (tp->snd_cwnd <= tp->snd_ssthresh) {
-		/* RFC3742: limited slow start
-		 * the window is increased by 1/K MSS for each arriving ACK,
-		 * for K = int(cwnd/(0.5 max_ssthresh))
-		 */
-		if (max_ssthresh > 0 && tp->snd_cwnd > max_ssthresh) {
-			u32 k = max(tp->snd_cwnd / (max_ssthresh >> 1), 1U);
-			if (++tp->snd_cwnd_cnt >= k) {
-				if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-					tp->snd_cwnd++;
-				tp->snd_cwnd_cnt = 0;
-			}
-		} else {
-			if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-				tp->snd_cwnd++;
-		}
-	} else {
+	if (tp->snd_cwnd <= tp->snd_ssthresh)
+		tcp_slow_start(tp);
+	else {
 		/* Update AIMD parameters.
 		 *
 		 * We want to guarantee that: