Commit b04c3320 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

tcp: add tcp_rtt_tsopt_us() 



Before adding usec TS support, add tcp_rtt_tsopt_us() helper
to factorize code.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9d0c00f5

net/ipv4/tcp_input.c

+23 −20
Original line number Diff line number Diff line
@@ -693,6 +693,21 @@ static inline void tcp_rcv_rtt_measure(struct tcp_sock *tp) 
	tp->rcv_rtt_est.time = tp->tcp_mstamp;

}



static s32 tcp_rtt_tsopt_us(const struct tcp_sock *tp)

{

	u32 delta, delta_us;



	delta = tcp_time_stamp_ts(tp) - tp->rx_opt.rcv_tsecr;



	if (likely(delta < INT_MAX / (USEC_PER_SEC / TCP_TS_HZ))) {

		if (!delta)

			delta = 1;

		delta_us = delta * (USEC_PER_SEC / TCP_TS_HZ);

		return delta_us;

	}

	return -1;

}



static inline void tcp_rcv_rtt_measure_ts(struct sock *sk,

					  const struct sk_buff *skb)

{
@@ -704,15 +719,10 @@ static inline void tcp_rcv_rtt_measure_ts(struct sock *sk, 


	if (TCP_SKB_CB(skb)->end_seq -

	    TCP_SKB_CB(skb)->seq >= inet_csk(sk)->icsk_ack.rcv_mss) {

		u32 delta = tcp_time_stamp_ts(tp) - tp->rx_opt.rcv_tsecr;

		u32 delta_us;

		s32 delta = tcp_rtt_tsopt_us(tp);



		if (likely(delta < INT_MAX / (USEC_PER_SEC / TCP_TS_HZ))) {

			if (!delta)

				delta = 1;

			delta_us = delta * (USEC_PER_SEC / TCP_TS_HZ);

			tcp_rcv_rtt_update(tp, delta_us, 0);

		}

		if (delta >= 0)

			tcp_rcv_rtt_update(tp, delta, 0);

	}

}
@@ -3146,17 +3156,10 @@ static bool tcp_ack_update_rtt(struct sock *sk, const int flag, 
	 * left edge of the send window.

	 * See draft-ietf-tcplw-high-performance-00, section 3.3.

	 */

	if (seq_rtt_us < 0 && tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr &&

	    flag & FLAG_ACKED) {

		u32 delta = tcp_time_stamp_ts(tp) - tp->rx_opt.rcv_tsecr;

	if (seq_rtt_us < 0 && tp->rx_opt.saw_tstamp &&

	    tp->rx_opt.rcv_tsecr && flag & FLAG_ACKED)

		seq_rtt_us = ca_rtt_us = tcp_rtt_tsopt_us(tp);



		if (likely(delta < INT_MAX / (USEC_PER_SEC / TCP_TS_HZ))) {

			if (!delta)

				delta = 1;

			seq_rtt_us = delta * (USEC_PER_SEC / TCP_TS_HZ);

			ca_rtt_us = seq_rtt_us;

		}

	}

	rs->rtt_us = ca_rtt_us; /* RTT of last (S)ACKed packet (or -1) */

	if (seq_rtt_us < 0)

		return false;