diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 72705eaf4b84060a45bf04d5170f389a18010eac..3dbea6610304627e590577ef2e8b7319c1e87c9c 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -350,6 +350,7 @@ struct tcp_sock {
 #endif
 
 /* Receiver side RTT estimation */
+	u32 rcv_rtt_last_tsecr;
 	struct {
 		u32	rtt_us;
 		u32	seq;
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 141acd92e58aeddeb9a0ba1eaacf3bd520a836a3..47c45d5be9f99f19a885cf40a97f1a12d58c5be5 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2563,6 +2563,7 @@ int tcp_disconnect(struct sock *sk, int flags)
 	sk->sk_shutdown = 0;
 	sock_reset_flag(sk, SOCK_DONE);
 	tp->srtt_us = 0;
+	tp->rcv_rtt_last_tsecr = 0;
 	tp->write_seq += tp->max_window + 2;
 	if (tp->write_seq == 0)
 		tp->write_seq = 1;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 355d3dffd021ccad0f30891994289d916f7d276c..76ca88f63b70b21bd2ec5c783471528b9599439b 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -582,9 +582,12 @@ static inline void tcp_rcv_rtt_measure_ts(struct sock *sk,
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 
-	if (tp->rx_opt.rcv_tsecr &&
-	    (TCP_SKB_CB(skb)->end_seq -
-	     TCP_SKB_CB(skb)->seq >= inet_csk(sk)->icsk_ack.rcv_mss)) {
+	if (tp->rx_opt.rcv_tsecr == tp->rcv_rtt_last_tsecr)
+		return;
+	tp->rcv_rtt_last_tsecr = tp->rx_opt.rcv_tsecr;
+
+	if (TCP_SKB_CB(skb)->end_seq -
+	    TCP_SKB_CB(skb)->seq >= inet_csk(sk)->icsk_ack.rcv_mss) {
 		u32 delta = tcp_time_stamp(tp) - tp->rx_opt.rcv_tsecr;
 		u32 delta_us;
 
@@ -5475,6 +5478,11 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb)
 				tcp_ack(sk, skb, 0);
 				__kfree_skb(skb);
 				tcp_data_snd_check(sk);
+				/* When receiving pure ack in fast path, update
+				 * last ts ecr directly instead of calling
+				 * tcp_rcv_rtt_measure_ts()
+				 */
+				tp->rcv_rtt_last_tsecr = tp->rx_opt.rcv_tsecr;
 				return;
 			} else { /* Header too small */
 				TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);