From 91ced13c64a69d472a81571e4b7a4195f5b8ce5b Mon Sep 17 00:00:00 2001
From: Yuchung Cheng <ycheng@google.com>
Date: Wed, 20 Mar 2013 13:32:59 +0000
Subject: [PATCH] --- yaml --- r: 368582 b: refs/heads/master c:
 ab42d9ee3d215ab74a49818ffc53771a88ce7ddf h: refs/heads/master v: v3

---
 [refs]                     |  2 +-
 trunk/net/ipv4/tcp_input.c | 42 +++++++++++++++++++++++---------------
 2 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/[refs] b/[refs]
index 2e3ff62241b0..1c0254bb1a8b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9b44190dc114c1720b34975b5bfc65aece112ced
+refs/heads/master: ab42d9ee3d215ab74a49818ffc53771a88ce7ddf
diff --git a/trunk/net/ipv4/tcp_input.c b/trunk/net/ipv4/tcp_input.c
index 231c79fe91f3..8d821e45b917 100644
--- a/trunk/net/ipv4/tcp_input.c
+++ b/trunk/net/ipv4/tcp_input.c
@@ -2664,6 +2664,30 @@ static void tcp_enter_recovery(struct sock *sk, bool ece_ack)
 	tcp_set_ca_state(sk, TCP_CA_Recovery);
 }
 
+/* Process an ACK in CA_Loss state. Move to CA_Open if lost data are
+ * recovered or spurious. Otherwise retransmits more on partial ACKs.
+ */
+static void tcp_process_loss(struct sock *sk, int flag)
+{
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	struct tcp_sock *tp = tcp_sk(sk);
+
+	if (!before(tp->snd_una, tp->high_seq)) {
+		icsk->icsk_retransmits = 0;
+		tcp_try_undo_recovery(sk);
+		return;
+	}
+
+	if (flag & FLAG_DATA_ACKED)
+		icsk->icsk_retransmits = 0;
+	if (tcp_is_reno(tp) && flag & FLAG_SND_UNA_ADVANCED)
+		tcp_reset_reno_sack(tp);
+	if (tcp_try_undo_loss(sk))
+		return;
+	tcp_moderate_cwnd(tp);
+	tcp_xmit_retransmit_queue(sk);
+}
+
 /* Process an event, which can update packets-in-flight not trivially.
  * Main goal of this function is to calculate new estimate for left_out,
  * taking into account both packets sitting in receiver's buffer and
@@ -2710,12 +2734,6 @@ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked,
 		tp->retrans_stamp = 0;
 	} else if (!before(tp->snd_una, tp->high_seq)) {
 		switch (icsk->icsk_ca_state) {
-		case TCP_CA_Loss:
-			icsk->icsk_retransmits = 0;
-			if (tcp_try_undo_recovery(sk))
-				return;
-			break;
-
 		case TCP_CA_CWR:
 			/* CWR is to be held something *above* high_seq
 			 * is ACKed for CWR bit to reach receiver. */
@@ -2746,18 +2764,10 @@ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked,
 		newly_acked_sacked = pkts_acked + tp->sacked_out - prior_sacked;
 		break;
 	case TCP_CA_Loss:
-		if (flag & FLAG_DATA_ACKED)
-			icsk->icsk_retransmits = 0;
-		if (tcp_is_reno(tp) && flag & FLAG_SND_UNA_ADVANCED)
-			tcp_reset_reno_sack(tp);
-		if (!tcp_try_undo_loss(sk)) {
-			tcp_moderate_cwnd(tp);
-			tcp_xmit_retransmit_queue(sk);
-			return;
-		}
+		tcp_process_loss(sk, flag);
 		if (icsk->icsk_ca_state != TCP_CA_Open)
 			return;
-		/* Loss is undone; fall through to processing in Open state. */
+		/* Fall through to processing in Open state. */
 	default:
 		if (tcp_is_reno(tp)) {
 			if (flag & FLAG_SND_UNA_ADVANCED)