From 6e588548c650cea30d365f5543471bed68f882e3 Mon Sep 17 00:00:00 2001
From: "David S. Miller" <davem@sunset.davemloft.net>
Date: Thu, 30 Aug 2007 22:10:28 -0700
Subject: [PATCH] --- yaml --- r: 64593 b: refs/heads/master c:
 05bb1fad1cde025a864a90cfeb98dcbefe78a44a h: refs/heads/master i:   64591:
 54fb139e3ada5f1e1385d3ddfbaca1af785378dc v: v3

---
 [refs]                          |  2 +-
 trunk/include/linux/rtnetlink.h |  2 ++
 trunk/net/ipv4/tcp_input.c      | 14 ++++++++++++--
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 025028e3629f..b5493df40a27 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 378be2c08314fc46e3f814fa264ff8ebdb79712f
+refs/heads/master: 05bb1fad1cde025a864a90cfeb98dcbefe78a44a
diff --git a/trunk/include/linux/rtnetlink.h b/trunk/include/linux/rtnetlink.h
index c91476ce314a..dff3192374f8 100644
--- a/trunk/include/linux/rtnetlink.h
+++ b/trunk/include/linux/rtnetlink.h
@@ -351,6 +351,8 @@ enum
 #define RTAX_INITCWND RTAX_INITCWND
 	RTAX_FEATURES,
 #define RTAX_FEATURES RTAX_FEATURES
+	RTAX_RTO_MIN,
+#define RTAX_RTO_MIN RTAX_RTO_MIN
 	__RTAX_MAX
 };
 
diff --git a/trunk/net/ipv4/tcp_input.c b/trunk/net/ipv4/tcp_input.c
index 9785df37a65f..1ee72127462b 100644
--- a/trunk/net/ipv4/tcp_input.c
+++ b/trunk/net/ipv4/tcp_input.c
@@ -555,6 +555,16 @@ static void tcp_event_data_recv(struct sock *sk, struct sk_buff *skb)
 		tcp_grow_window(sk, skb);
 }
 
+static u32 tcp_rto_min(struct sock *sk)
+{
+	struct dst_entry *dst = __sk_dst_get(sk);
+	u32 rto_min = TCP_RTO_MIN;
+
+	if (dst_metric_locked(dst, RTAX_RTO_MIN))
+		rto_min = dst->metrics[RTAX_RTO_MIN-1];
+	return rto_min;
+}
+
 /* Called to compute a smoothed rtt estimate. The data fed to this
  * routine either comes from timestamps, or from segments that were
  * known _not_ to have been retransmitted [see Karn/Partridge
@@ -616,13 +626,13 @@ static void tcp_rtt_estimator(struct sock *sk, const __u32 mrtt)
 			if (tp->mdev_max < tp->rttvar)
 				tp->rttvar -= (tp->rttvar-tp->mdev_max)>>2;
 			tp->rtt_seq = tp->snd_nxt;
-			tp->mdev_max = TCP_RTO_MIN;
+			tp->mdev_max = tcp_rto_min(sk);
 		}
 	} else {
 		/* no previous measure. */
 		tp->srtt = m<<3;	/* take the measured time to be rtt */
 		tp->mdev = m<<1;	/* make sure rto = 3*rtt */
-		tp->mdev_max = tp->rttvar = max(tp->mdev, TCP_RTO_MIN);
+		tp->mdev_max = tp->rttvar = max(tp->mdev, tcp_rto_min(sk));
 		tp->rtt_seq = tp->snd_nxt;
 	}
 }