diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 748980862a09e..f7b3e37d21985 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1006,7 +1006,11 @@ static void tcp_check_sack_reordering(struct sock *sk, const u32 low_seq,
 		      ts ? LINUX_MIB_TCPTSREORDER : LINUX_MIB_TCPSACKREORDER);
 }
 
-/* This must be called before lost_out is incremented */
+ /* This must be called before lost_out or retrans_out are updated
+  * on a new loss, because we want to know if all skbs previously
+  * known to be lost have already been retransmitted, indicating
+  * that this newly lost skb is our next skb to retransmit.
+  */
 static void tcp_verify_retransmit_hint(struct tcp_sock *tp, struct sk_buff *skb)
 {
 	if ((!tp->retransmit_skb_hint && tp->retrans_out >= tp->lost_out) ||
@@ -1016,39 +1020,24 @@ static void tcp_verify_retransmit_hint(struct tcp_sock *tp, struct sk_buff *skb)
 		tp->retransmit_skb_hint = skb;
 }
 
-/* Sum the number of packets on the wire we have marked as lost.
- * There are two cases we care about here:
- * a) Packet hasn't been marked lost (nor retransmitted),
- *    and this is the first loss.
- * b) Packet has been marked both lost and retransmitted,
- *    and this means we think it was lost again.
- */
-static void tcp_sum_lost(struct tcp_sock *tp, struct sk_buff *skb)
+void tcp_mark_skb_lost(struct sock *sk, struct sk_buff *skb)
 {
 	__u8 sacked = TCP_SKB_CB(skb)->sacked;
+	struct tcp_sock *tp = tcp_sk(sk);
 
-	if (!(sacked & TCPCB_LOST) ||
-	    ((sacked & TCPCB_LOST) && (sacked & TCPCB_SACKED_RETRANS)))
-		tp->lost += tcp_skb_pcount(skb);
-}
-
-static void tcp_skb_mark_lost(struct tcp_sock *tp, struct sk_buff *skb)
-{
-	if (!(TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_ACKED))) {
-		tcp_verify_retransmit_hint(tp, skb);
-
-		tp->lost_out += tcp_skb_pcount(skb);
-		tcp_sum_lost(tp, skb);
-		TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
-	}
-}
+	if (sacked & TCPCB_SACKED_ACKED)
+		return;
 
-void tcp_skb_mark_lost_uncond_verify(struct tcp_sock *tp, struct sk_buff *skb)
-{
 	tcp_verify_retransmit_hint(tp, skb);
-
-	tcp_sum_lost(tp, skb);
-	if (!(TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_ACKED))) {
+	if (sacked & TCPCB_LOST) {
+		if (sacked & TCPCB_SACKED_RETRANS) {
+			/* Account for retransmits that are lost again */
+			TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
+			tp->retrans_out -= tcp_skb_pcount(skb);
+			NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPLOSTRETRANSMIT,
+				      tcp_skb_pcount(skb));
+		}
+	} else {
 		tp->lost_out += tcp_skb_pcount(skb);
 		TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
 	}
@@ -2308,7 +2297,8 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
 		if (cnt > packets)
 			break;
 
-		tcp_skb_mark_lost(tp, skb);
+		if (!(TCP_SKB_CB(skb)->sacked & TCPCB_LOST))
+			tcp_mark_skb_lost(sk, skb);
 
 		if (mark_head)
 			break;
@@ -2674,14 +2664,8 @@ void tcp_simple_retransmit(struct sock *sk)
 	unsigned int mss = tcp_current_mss(sk);
 
 	skb_rbtree_walk(skb, &sk->tcp_rtx_queue) {
-		if (tcp_skb_seglen(skb) > mss &&
-		    !(TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) {
-			if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) {
-				TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
-				tp->retrans_out -= tcp_skb_pcount(skb);
-			}
-			tcp_skb_mark_lost_uncond_verify(tp, skb);
-		}
+		if (tcp_skb_seglen(skb) > mss)
+			tcp_mark_skb_lost(sk, skb);
 	}
 
 	tcp_clear_retrans_hints_partial(tp);
diff --git a/net/ipv4/tcp_recovery.c b/net/ipv4/tcp_recovery.c
index fdb715bdd2d11..f65a3ddd0d58a 100644
--- a/net/ipv4/tcp_recovery.c
+++ b/net/ipv4/tcp_recovery.c
@@ -2,20 +2,6 @@
 #include <linux/tcp.h>
 #include <net/tcp.h>
 
-void tcp_mark_skb_lost(struct sock *sk, struct sk_buff *skb)
-{
-	struct tcp_sock *tp = tcp_sk(sk);
-
-	tcp_skb_mark_lost_uncond_verify(tp, skb);
-	if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) {
-		/* Account for retransmits that are lost again */
-		TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
-		tp->retrans_out -= tcp_skb_pcount(skb);
-		NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPLOSTRETRANSMIT,
-			      tcp_skb_pcount(skb));
-	}
-}
-
 static bool tcp_rack_sent_after(u64 t1, u64 t2, u32 seq1, u32 seq2)
 {
 	return t1 > t2 || (t1 == t2 && after(seq1, seq2));
@@ -246,6 +232,6 @@ void tcp_newreno_mark_lost(struct sock *sk, bool snd_una_advanced)
 			tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb,
 				     mss, mss, GFP_ATOMIC);
 
-		tcp_skb_mark_lost_uncond_verify(tp, skb);
+		tcp_mark_skb_lost(sk, skb);
 	}
 }