[PATCH net] tcp: refresh tcp_mstamp from timers callbacks

[PATCH net] tcp: refresh tcp_mstamp from timers callbacks

[Eric Dumazet]

From: Eric Dumazet <edumazet@google.com>

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>
---
 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 16df6dd44b988a128d97df3a7953437499a216e8..968fda1983762e6d7c078a28ccfcbd9066788daf 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);
 	}
@@ -632,6 +633,7 @@ static void tcp_keepalive_timer (struct timer_list *t)
 		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;

Re: [PATCH net] tcp: refresh tcp_mstamp from timers callbacks

[Neal Cardwell]

On Tue, Dec 12, 2017 at 9:22 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> 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>

Thanks, Eric!

neal

Re: [PATCH net] tcp: refresh tcp_mstamp from timers callbacks

[Soheil Hassas Yeganeh]

On Tue, Dec 12, 2017 at 9:26 PM, Neal Cardwell <ncardwell@google.com> wrote:
> On Tue, Dec 12, 2017 at 9:22 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>> From: Eric Dumazet <edumazet@google.com>
>>
>> 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>
>
> Thanks, Eric!
>
> neal

Acked-by: Soheil Hassas Yeganeh <soheil@google.com>

This is a very nice catch! Thank you Eric!

Re: [PATCH net] tcp: refresh tcp_mstamp from timers callbacks

[Mike Maloney]

Acked-by:  Mike Maloney <maloney@google.com>

Thanks for the quick fix!

On Tue, Dec 12, 2017 at 9:42 PM, Soheil Hassas Yeganeh
<soheil.kdev@gmail.com> wrote:
> On Tue, Dec 12, 2017 at 9:26 PM, Neal Cardwell <ncardwell@google.com> wrote:
>> On Tue, Dec 12, 2017 at 9:22 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>>> From: Eric Dumazet <edumazet@google.com>
>>>
>>> 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>
>>
>> Thanks, Eric!
>>
>> neal
>
> Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
>
> This is a very nice catch! Thank you Eric!

Re: [PATCH net] tcp: refresh tcp_mstamp from timers callbacks

[David Miller]

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 12 Dec 2017 18:22:52 -0800

> From: Eric Dumazet <edumazet@google.com>
> 
> 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>

Applied and queued up for -stable, thanks Eric.