From a51f5f604afd81089a3871fcdbe25578072c9d67 Mon Sep 17 00:00:00 2001
From: Neal Cardwell <ncardwell@google.com>
Date: Wed, 16 Nov 2011 08:58:03 +0000
Subject: [PATCH] --- yaml --- r: 277982 b: refs/heads/master c:
 e95ae2f2cf10f7bf27b492aa6188f3cd745de162 h: refs/heads/master v: v3

---
 [refs]                     |  2 +-
 trunk/net/ipv4/tcp_input.c | 10 +++++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 9083d15df039..a9a128606ef3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5628adf1a0ff39b9e76e1a8e1c94dadabfd46914
+refs/heads/master: e95ae2f2cf10f7bf27b492aa6188f3cd745de162
diff --git a/trunk/net/ipv4/tcp_input.c b/trunk/net/ipv4/tcp_input.c
index b49e41864037..751d39060fb8 100644
--- a/trunk/net/ipv4/tcp_input.c
+++ b/trunk/net/ipv4/tcp_input.c
@@ -3805,10 +3805,14 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	return -1;
 
 old_ack:
+	/* If data was SACKed, tag it and see if we should send more data.
+	 * If data was DSACKed, see if we can undo a cwnd reduction.
+	 */
 	if (TCP_SKB_CB(skb)->sacked) {
-		tcp_sacktag_write_queue(sk, skb, prior_snd_una);
-		if (icsk->icsk_ca_state == TCP_CA_Open)
-			tcp_try_keep_open(sk);
+		flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una);
+		newly_acked_sacked = tp->sacked_out - prior_sacked;
+		tcp_fastretrans_alert(sk, pkts_acked, newly_acked_sacked,
+				      is_dupack, flag);
 	}
 
 	SOCK_DEBUG(sk, "Ack %u before %u:%u\n", ack, tp->snd_una, tp->snd_nxt);