tcp: update delivered_ce with delivered

Currently tp->delivered is updated in various places in tcp_ack() but
tp->delivered_ce is updated once at the end. As a result two counts in
OPT_STATS of SCM_TSTAMP_ACK timestamps generated in tcp_ack() may not be
in sync. This patch updates both counts at the same in tcp_ack().

Signed-off-by: Yousuk Seung <ysseung@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: yousukseung

net/ipv4/tcp_input.c

@@ -962,6 +962,15 @@ void tcp_skb_mark_lost_uncond_verify(struct tcp_sock *tp, struct sk_buff *skb)
 	}
 }
 
+/* Updates the delivered and delivered_ce counts */
+static void tcp_count_delivered(struct tcp_sock *tp, u32 delivered,
+				bool ece_ack)
+{
+	tp->delivered += delivered;
+	if (ece_ack)
+		tp->delivered_ce += delivered;
+}
+
 /* This procedure tags the retransmission queue when SACKs arrive.
  *
  * We have three tag bits: SACKED(S), RETRANS(R) and LOST(L).
@@ -1259,7 +1268,7 @@ static u8 tcp_sacktag_one(struct sock *sk,
 		sacked |= TCPCB_SACKED_ACKED;
 		state->flag |= FLAG_DATA_SACKED;
 		tp->sacked_out += pcount;
-		tp->delivered += pcount;  /* Out-of-order packets delivered */
+		/* Out-of-order packets delivered */
 		state->sack_delivered += pcount;
 
 		/* Lost marker hint past SACKed? Tweak RFC3517 cnt */
@@ -1686,7 +1695,7 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
 					 num_sacks, prior_snd_una);
 	if (found_dup_sack) {
 		state->flag |= FLAG_DSACKING_ACK;
-		tp->delivered++; /* A spurious retransmission is delivered */
+		/* A spurious retransmission is delivered */
 		state->sack_delivered++;
 	}
 
@@ -1907,7 +1916,7 @@ static void tcp_add_reno_sack(struct sock *sk, int num_dupack, bool ece_ack)
 		tcp_check_reno_reordering(sk, 0);
 		delivered = tp->sacked_out - prior_sacked;
 		if (delivered > 0)
-			tp->delivered += delivered;
+			tcp_count_delivered(tp, delivered, ece_ack);
 		tcp_verify_left_out(tp);
 	}
 }
@@ -1920,7 +1929,8 @@ static void tcp_remove_reno_sacks(struct sock *sk, int acked, bool ece_ack)
 
 	if (acked > 0) {
 		/* One ACK acked hole. The rest eat duplicate ACKs. */
-		tp->delivered += max_t(int, acked - tp->sacked_out, 1);
+		tcp_count_delivered(tp, max_t(int, acked - tp->sacked_out, 1),
+				    ece_ack);
 		if (acked - 1 >= tp->sacked_out)
 			tp->sacked_out = 0;
 		else
@@ -3116,7 +3126,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack,
 		if (sacked & TCPCB_SACKED_ACKED) {
 			tp->sacked_out -= acked_pcount;
 		} else if (tcp_is_sack(tp)) {
-			tp->delivered += acked_pcount;
+			tcp_count_delivered(tp, acked_pcount, ece_ack);
 			if (!tcp_skb_spurious_retrans(tp, skb))
 				tcp_rack_advance(tp, sacked, scb->end_seq,
 						 tcp_skb_timestamp_us(skb));
@@ -3562,10 +3572,9 @@ static u32 tcp_newly_delivered(struct sock *sk, u32 prior_delivered, int flag)
 
 	delivered = tp->delivered - prior_delivered;
 	NET_ADD_STATS(net, LINUX_MIB_TCPDELIVERED, delivered);
-	if (flag & FLAG_ECE) {
-		tp->delivered_ce += delivered;
+	if (flag & FLAG_ECE)
 		NET_ADD_STATS(net, LINUX_MIB_TCPDELIVEREDCE, delivered);
-	}
+
 	return delivered;
 }
 
@@ -3665,6 +3674,10 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 			ack_ev_flags |= CA_ACK_ECE;
 		}
 
+		if (sack_state.sack_delivered)
+			tcp_count_delivered(tp, sack_state.sack_delivered,
+					    flag & FLAG_ECE);
+
 		if (flag & FLAG_WIN_UPDATE)
 			ack_ev_flags |= CA_ACK_WIN_UPDATE;