Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b17b8a20 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

tcp: fix tcp_rearm_rto() 



skbs in (re)transmit queue no longer have a copy of jiffies
at the time of the transmit : skb->skb_mstamp is now in usec unit,
with no correlation to tcp_jiffies32.

We have to convert rto from jiffies to usec, compute a time difference
in usec, then convert the delta to HZ units.

Fixes: 9a568de4 ("tcp: switch TCP TS option (RFC 7323) to 1ms clock")
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4454e866

net/ipv4/tcp_input.c

+6 −6
Original line number Diff line number Diff line
@@ -3002,14 +3002,14 @@ void tcp_rearm_rto(struct sock *sk) 
		if (icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||

		    icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {

			struct sk_buff *skb = tcp_write_queue_head(sk);

			const u32 rto_time_stamp =

				tcp_skb_timestamp(skb) + rto;

			s32 delta = (s32)(rto_time_stamp - tcp_jiffies32);

			/* delta may not be positive if the socket is locked

			u64 rto_time_stamp = skb->skb_mstamp +

					     jiffies_to_usecs(rto);

			s64 delta_us = rto_time_stamp - tp->tcp_mstamp;

			/* delta_us may not be positive if the socket is locked

			 * when the retrans timer fires and is rescheduled.

			 */

			if (delta > 0)

				rto = delta;

			if (delta_us > 0)

				rto = usecs_to_jiffies(delta_us);

		}

		inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, rto,

					  TCP_RTO_MAX);