Commit 4cd82999 authored by Ilpo Järvinen's avatar Ilpo Järvinen Committed by David S. Miller
Browse files

[TCP]: No need to re-count fackets_out/sacked_out at RTO 



Both sacked_out and fackets_out are directly known from how
parameter. Since fackets_out is accurate, there's no need for
recounting (sacked_out was previously unnecessarily counted
in the loop anyway).

Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d1935942

net/ipv4/tcp_input.c

+16 −10
Original line number Diff line number Diff line
@@ -1711,18 +1711,23 @@ static void tcp_enter_frto_loss(struct sock *sk, int allowed_segments, int flag) 
	tcp_clear_retrans_hints_partial(tp);

}



void tcp_clear_retrans(struct tcp_sock *tp)

static void tcp_clear_retrans_partial(struct tcp_sock *tp)

{

	tp->retrans_out = 0;



	tp->fackets_out = 0;

	tp->sacked_out = 0;

	tp->lost_out = 0;



	tp->undo_marker = 0;

	tp->undo_retrans = 0;

}



void tcp_clear_retrans(struct tcp_sock *tp)

{

	tcp_clear_retrans_partial(tp);



	tp->fackets_out = 0;

	tp->sacked_out = 0;

}



/* Enter Loss state. If "how" is not zero, forget all SACK information

 * and reset tags completely, otherwise preserve SACKs. If receiver

 * dropped its ofo queue, we will know this due to reneging detection.
@@ -1732,7 +1737,6 @@ void tcp_enter_loss(struct sock *sk, int how) 
	const struct inet_connection_sock *icsk = inet_csk(sk);

	struct tcp_sock *tp = tcp_sk(sk);

	struct sk_buff *skb;

	int cnt = 0;



	/* Reduce ssthresh if it has not yet been made inside this window. */

	if (icsk->icsk_ca_state <= TCP_CA_Disorder || tp->snd_una == tp->high_seq ||
@@ -1746,7 +1750,10 @@ void tcp_enter_loss(struct sock *sk, int how) 
	tp->snd_cwnd_stamp = tcp_time_stamp;



	tp->bytes_acked = 0;

	tcp_clear_retrans(tp);

	tcp_clear_retrans_partial(tp);



	if (tcp_is_reno(tp))

		tcp_reset_reno_sack(tp);



	if (!how) {

		/* Push undo marker, if it was plain RTO and nothing
@@ -1754,13 +1761,15 @@ void tcp_enter_loss(struct sock *sk, int how) 
		tp->undo_marker = tp->snd_una;

		tcp_clear_retrans_hints_partial(tp);

	} else {

		tp->sacked_out = 0;

		tp->fackets_out = 0;

		tcp_clear_all_retrans_hints(tp);

	}



	tcp_for_write_queue(skb, sk) {

		if (skb == tcp_send_head(sk))

			break;

		cnt += tcp_skb_pcount(skb);



		if (TCP_SKB_CB(skb)->sacked&TCPCB_RETRANS)

			tp->undo_marker = 0;

		TCP_SKB_CB(skb)->sacked &= (~TCPCB_TAGBITS)|TCPCB_SACKED_ACKED;
@@ -1768,9 +1777,6 @@ void tcp_enter_loss(struct sock *sk, int how) 
			TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_ACKED;

			TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;

			tp->lost_out += tcp_skb_pcount(skb);

		} else {

			tp->sacked_out += tcp_skb_pcount(skb);

			tp->fackets_out = cnt;

		}

	}

	tcp_verify_left_out(tp);

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