From: Eric Dumazet <edumazet@google.com>
Date: Tue, 12 Dec 2017 18:22:52 -0800
Subject: tcp: refresh tcp_mstamp from timers callbacks
Patch-mainline: v4.15-rc4
Git-commit: 4688eb7cf3ae2c2721d1dacff5c1384cba47d176
References: bsc#1061739

Only the retransmit timer currently refreshes tcp_mstamp

We should do the same for delayed acks and keepalives.

Even if RFC 7323 does not request it, this is consistent to what linux
did in the past, when TS values were based on jiffies.

Fixes: 385e20706fac ("tcp: use tp->tcp_mstamp in output path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Mike Maloney <maloney@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by:  Mike Maloney <maloney@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Kubecek <mkubecek@suse.cz>

---
 net/ipv4/tcp_timer.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 655dd8d7f064..e9af1879cd53 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -264,6 +264,7 @@ void tcp_delack_timer_handler(struct sock *sk)
 			icsk->icsk_ack.pingpong = 0;
 			icsk->icsk_ack.ato      = TCP_ATO_MIN;
 		}
+		tcp_mstamp_refresh(tcp_sk(sk));
 		tcp_send_ack(sk);
 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKS);
 	}
@@ -627,6 +628,7 @@ static void tcp_keepalive_timer (unsigned long data)
 		goto out;
 	}
 
+	tcp_mstamp_refresh(tp);
 	if (sk->sk_state == TCP_FIN_WAIT2 && sock_flag(sk, SOCK_DEAD)) {
 		if (tp->linger2 >= 0) {
 			const int tmo = tcp_fin_time(sk) - TCP_TIMEWAIT_LEN;
-- 
2.15.1