Commit c634e34f authored by Yousuk Seung's avatar Yousuk Seung Committed by David S. Miller
Browse files

tcp: add ece_ack flag to reno sack functions 



Pass a boolean flag that tells the ECE state of the current ack to reno
sack functions. This is pure refactor for future patches to improve
tracking delivered counts.

Signed-off-by: default avatarYousuk Seung <ysseung@google.com>
Signed-off-by: default avatarYuchung Cheng <ycheng@google.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarNeal Cardwell <ncardwell@google.com>
Acked-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent fdb7eb21

net/ipv4/tcp_input.c

+12 −10
Original line number Diff line number Diff line
@@ -1893,7 +1893,7 @@ static void tcp_check_reno_reordering(struct sock *sk, const int addend) 


/* Emulate SACKs for SACKless connection: account for a new dupack. */



static void tcp_add_reno_sack(struct sock *sk, int num_dupack)

static void tcp_add_reno_sack(struct sock *sk, int num_dupack, bool ece_ack)

{

	if (num_dupack) {

		struct tcp_sock *tp = tcp_sk(sk);
@@ -1911,7 +1911,7 @@ static void tcp_add_reno_sack(struct sock *sk, int num_dupack) 


/* Account for ACK, ACKing some data in Reno Recovery phase. */



static void tcp_remove_reno_sacks(struct sock *sk, int acked)

static void tcp_remove_reno_sacks(struct sock *sk, int acked, bool ece_ack)

{

	struct tcp_sock *tp = tcp_sk(sk);
@@ -2697,7 +2697,7 @@ static void tcp_process_loss(struct sock *sk, int flag, int num_dupack, 
		 * delivered. Lower inflight to clock out (re)tranmissions.

		 */

		if (after(tp->snd_nxt, tp->high_seq) && num_dupack)

			tcp_add_reno_sack(sk, num_dupack);

			tcp_add_reno_sack(sk, num_dupack, flag & FLAG_ECE);

		else if (flag & FLAG_SND_UNA_ADVANCED)

			tcp_reset_reno_sack(tp);

	}
@@ -2779,6 +2779,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, 
	struct inet_connection_sock *icsk = inet_csk(sk);

	struct tcp_sock *tp = tcp_sk(sk);

	int fast_rexmit = 0, flag = *ack_flag;

	bool ece_ack = flag & FLAG_ECE;

	bool do_lost = num_dupack || ((flag & FLAG_DATA_SACKED) &&

				      tcp_force_fast_retransmit(sk));
@@ -2787,7 +2788,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, 


	/* Now state machine starts.

	 * A. ECE, hence prohibit cwnd undoing, the reduction is required. */

	if (flag & FLAG_ECE)

	if (ece_ack)

		tp->prior_ssthresh = 0;



	/* B. In all the states check for reneging SACKs. */
@@ -2828,7 +2829,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, 
	case TCP_CA_Recovery:

		if (!(flag & FLAG_SND_UNA_ADVANCED)) {

			if (tcp_is_reno(tp))

				tcp_add_reno_sack(sk, num_dupack);

				tcp_add_reno_sack(sk, num_dupack, ece_ack);

		} else {

			if (tcp_try_undo_partial(sk, prior_snd_una))

				return;
@@ -2853,7 +2854,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, 
		if (tcp_is_reno(tp)) {

			if (flag & FLAG_SND_UNA_ADVANCED)

				tcp_reset_reno_sack(tp);

			tcp_add_reno_sack(sk, num_dupack);

			tcp_add_reno_sack(sk, num_dupack, ece_ack);

		}



		if (icsk->icsk_ca_state <= TCP_CA_Disorder)
@@ -2877,7 +2878,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, 
		}



		/* Otherwise enter Recovery state */

		tcp_enter_recovery(sk, (flag & FLAG_ECE));

		tcp_enter_recovery(sk, ece_ack);

		fast_rexmit = 1;

	}
@@ -3053,7 +3054,7 @@ static void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb, 
 */

static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack,

			       u32 prior_snd_una,

			       struct tcp_sacktag_state *sack)

			       struct tcp_sacktag_state *sack, bool ece_ack)

{

	const struct inet_connection_sock *icsk = inet_csk(sk);

	u64 first_ackt, last_ackt;
@@ -3191,7 +3192,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack, 
		}



		if (tcp_is_reno(tp)) {

			tcp_remove_reno_sacks(sk, pkts_acked);

			tcp_remove_reno_sacks(sk, pkts_acked, ece_ack);



			/* If any of the cumulatively ACKed segments was

			 * retransmitted, non-SACK case cannot confirm that
@@ -3685,7 +3686,8 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) 
		goto no_queue;



	/* See if we can take anything off of the retransmit queue. */

	flag |= tcp_clean_rtx_queue(sk, prior_fack, prior_snd_una, &sack_state);

	flag |= tcp_clean_rtx_queue(sk, prior_fack, prior_snd_una, &sack_state,

				    flag & FLAG_ECE);



	tcp_rack_update_reo_wnd(sk, &rs);

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