1 files changed, 25 insertions, 34 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index b55f60f6fcb..3357f69e353 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -182,7 +182,7 @@ static void tcp_incr_quickack(struct sock *sk)
 		icsk->icsk_ack.quick = min(quickacks, TCP_MAX_QUICKACKS);
 }
 
-void tcp_enter_quickack_mode(struct sock *sk)
+static void tcp_enter_quickack_mode(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	tcp_incr_quickack(sk);
@@ -428,10 +428,10 @@ EXPORT_SYMBOL(tcp_initialize_rcv_mss);
  *
  * The algorithm for RTT estimation w/o timestamps is based on
  * Dynamic Right-Sizing (DRS) by Wu Feng and Mike Fisk of LANL.
- * <http://www.lanl.gov/radiant/website/pubs/drs/lacsi2001.ps>
+ * <http://public.lanl.gov/radiant/pubs.html#DRS>
  *
  * More detail on this code can be found at
- * <http://www.psc.edu/~jheffner/senior_thesis.ps>,
+ * <http://staff.psc.edu/jheffner/>,
  * though this reference is out of date.  A new paper
  * is pending.
  */
@@ -805,25 +805,12 @@ void tcp_update_metrics(struct sock *sk)
 	}
 }
 
-/* Numbers are taken from RFC3390.
- *
- * John Heffner states:
- *
- *	The RFC specifies a window of no more than 4380 bytes
- *	unless 2*MSS > 4380.  Reading the pseudocode in the RFC
- *	is a bit misleading because they use a clamp at 4380 bytes
- *	rather than use a multiplier in the relevant range.
- */
 __u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst)
 {
 	__u32 cwnd = (dst ? dst_metric(dst, RTAX_INITCWND) : 0);
 
-	if (!cwnd) {
-		if (tp->mss_cache > 1460)
-			cwnd = 2;
-		else
-			cwnd = (tp->mss_cache > 1095) ? 3 : 4;
-	}
+	if (!cwnd)
+		cwnd = rfc3390_bytes_to_packets(tp->mss_cache);
 	return min_t(__u32, cwnd, tp->snd_cwnd_clamp);
 }
 
@@ -2314,7 +2301,7 @@ static inline int tcp_dupack_heuristics(struct tcp_sock *tp)
 
 static inline int tcp_skb_timedout(struct sock *sk, struct sk_buff *skb)
 {
-	return (tcp_time_stamp - TCP_SKB_CB(skb)->when > inet_csk(sk)->icsk_rto);
+	return tcp_time_stamp - TCP_SKB_CB(skb)->when > inet_csk(sk)->icsk_rto;
 }
 
 static inline int tcp_head_timedout(struct sock *sk)
@@ -2508,7 +2495,7 @@ static void tcp_timeout_skbs(struct sock *sk)
 /* Mark head of queue up as lost. With RFC3517 SACK, the packets is
  * is against sacked "cnt", otherwise it's against facked "cnt"
  */
-static void tcp_mark_head_lost(struct sock *sk, int packets)
+static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct sk_buff *skb;
@@ -2516,13 +2503,13 @@ static void tcp_mark_head_lost(struct sock *sk, int packets)
 	int err;
 	unsigned int mss;
 
-	if (packets == 0)
-		return;
-
 	WARN_ON(packets > tp->packets_out);
 	if (tp->lost_skb_hint) {
 		skb = tp->lost_skb_hint;
 		cnt = tp->lost_cnt_hint;
+		/* Head already handled? */
+		if (mark_head && skb != tcp_write_queue_head(sk))
+			return;
 	} else {
 		skb = tcp_write_queue_head(sk);
 		cnt = 0;
@@ -2557,6 +2544,9 @@ static void tcp_mark_head_lost(struct sock *sk, int packets)
 		}
 
 		tcp_skb_mark_lost(tp, skb);
+
+		if (mark_head)
+			break;
 	}
 	tcp_verify_left_out(tp);
 }
@@ -2568,17 +2558,18 @@ static void tcp_update_scoreboard(struct sock *sk, int fast_rexmit)
 	struct tcp_sock *tp = tcp_sk(sk);
 
 	if (tcp_is_reno(tp)) {
-		tcp_mark_head_lost(sk, 1);
+		tcp_mark_head_lost(sk, 1, 1);
 	} else if (tcp_is_fack(tp)) {
 		int lost = tp->fackets_out - tp->reordering;
 		if (lost <= 0)
 			lost = 1;
-		tcp_mark_head_lost(sk, lost);
+		tcp_mark_head_lost(sk, lost, 0);
 	} else {
 		int sacked_upto = tp->sacked_out - tp->reordering;
-		if (sacked_upto < fast_rexmit)
-			sacked_upto = fast_rexmit;
-		tcp_mark_head_lost(sk, sacked_upto);
+		if (sacked_upto >= 0)
+			tcp_mark_head_lost(sk, sacked_upto, 0);
+		else if (fast_rexmit)
+			tcp_mark_head_lost(sk, 1, 1);
 	}
 
 	tcp_timeout_skbs(sk);
@@ -2887,7 +2878,7 @@ static void tcp_mtup_probe_success(struct sock *sk)
 		       icsk->icsk_mtup.probe_size;
 	tp->snd_cwnd_cnt = 0;
 	tp->snd_cwnd_stamp = tcp_time_stamp;
-	tp->rcv_ssthresh = tcp_current_ssthresh(sk);
+	tp->snd_ssthresh = tcp_current_ssthresh(sk);
 
 	icsk->icsk_mtup.search_low = icsk->icsk_mtup.probe_size;
 	icsk->icsk_mtup.probe_size = 0;
@@ -2984,7 +2975,7 @@ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked, int flag)
 	    before(tp->snd_una, tp->high_seq) &&
 	    icsk->icsk_ca_state != TCP_CA_Open &&
 	    tp->fackets_out > tp->reordering) {
-		tcp_mark_head_lost(sk, tp->fackets_out - tp->reordering);
+		tcp_mark_head_lost(sk, tp->fackets_out - tp->reordering, 0);
 		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPLOSS);
 	}
 
@@ -3412,8 +3403,8 @@ static void tcp_ack_probe(struct sock *sk)
 
 static inline int tcp_ack_is_dubious(const struct sock *sk, const int flag)
 {
-	return (!(flag & FLAG_NOT_DUP) || (flag & FLAG_CA_ALERT) ||
-		inet_csk(sk)->icsk_ca_state != TCP_CA_Open);
+	return !(flag & FLAG_NOT_DUP) || (flag & FLAG_CA_ALERT) ||
+		inet_csk(sk)->icsk_ca_state != TCP_CA_Open;
 }
 
 static inline int tcp_may_raise_cwnd(const struct sock *sk, const int flag)
@@ -3430,9 +3421,9 @@ static inline int tcp_may_update_window(const struct tcp_sock *tp,
 					const u32 ack, const u32 ack_seq,
 					const u32 nwin)
 {
-	return (after(ack, tp->snd_una) ||
+	return	after(ack, tp->snd_una) ||
 		after(ack_seq, tp->snd_wl1) ||
-		(ack_seq == tp->snd_wl1 && nwin > tp->snd_wnd));
+		(ack_seq == tp->snd_wl1 && nwin > tp->snd_wnd);
 }
 
 /* Update our send window.