3 files changed, 10 insertions, 3 deletions

diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h
index 7a2144e1afae..eb0f1a554d7b 100644
--- a/include/uapi/linux/rtnetlink.h
+++ b/include/uapi/linux/rtnetlink.h
@@ -386,6 +386,8 @@ enum {
 #define RTAX_RTO_MIN RTAX_RTO_MIN
         RTAX_INITRWND,
 #define RTAX_INITRWND RTAX_INITRWND
+        RTAX_QUICKACK,
+#define RTAX_QUICKACK RTAX_QUICKACK
         __RTAX_MAX
 };
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 46271cdcf088..28af45abe062 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3717,6 +3717,7 @@ void tcp_reset(struct sock *sk)
 static void tcp_fin(struct sock *sk)
 {
         struct tcp_sock *tp = tcp_sk(sk);
+        const struct dst_entry *dst;
 
         inet_csk_schedule_ack(sk);
 
@@ -3728,7 +3729,9 @@ static void tcp_fin(struct sock *sk)
         case TCP_ESTABLISHED:
                 /* Move to CLOSE_WAIT */
                 tcp_set_state(sk, TCP_CLOSE_WAIT);
-                inet_csk(sk)->icsk_ack.pingpong = 1;
+                dst = __sk_dst_get(sk);
+                if (!dst || !dst_metric(dst, RTAX_QUICKACK))
+                        inet_csk(sk)->icsk_ack.pingpong = 1;
                 break;
 
         case TCP_CLOSE_WAIT:
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e2c1333ee318..3d609490f118 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -160,6 +160,7 @@ static void tcp_event_data_sent(struct tcp_sock *tp,
 {
         struct inet_connection_sock *icsk = inet_csk(sk);
         const u32 now = tcp_time_stamp;
+        const struct dst_entry *dst = __sk_dst_get(sk);
 
         if (sysctl_tcp_slow_start_after_idle &&
             (!tp->packets_out && (s32)(now - tp->lsndtime) > icsk->icsk_rto))
@@ -170,8 +171,9 @@ static void tcp_event_data_sent(struct tcp_sock *tp,
         /* If it is a reply for ato after last received
          * packet, enter pingpong mode.
          */
-        if ((u32)(now - icsk->icsk_ack.lrcvtime) < icsk->icsk_ack.ato)
-                icsk->icsk_ack.pingpong = 1;
+        if ((u32)(now - icsk->icsk_ack.lrcvtime) < icsk->icsk_ack.ato &&
+            (!dst || !dst_metric(dst, RTAX_QUICKACK)))
+                        icsk->icsk_ack.pingpong = 1;
 }
 
 /* Account for an ACK we sent. */