net/ipv4/tcp_input.c

1014 	int	flag;
1040 		state->flag |= FLAG_DSACK_TLP;
1054 	if (tp->reord_seen && !(state->flag & FLAG_DSACK_TLP))
1057 	state->flag |= FLAG_DSACKING_ACK;
1427 					state->flag |= FLAG_ORIG_SACK_ACKED;
1440 		state->flag |= FLAG_DATA_SACKED;
1861 	state->flag = 0;
2037 	return state->flag;
2362 static bool tcp_time_to_recover(struct sock *sk, int flag)
2666 void tcp_cwnd_reduction(struct sock *sk, int newly_acked_sacked, int newly_lost, int flag)
2683 		if (flag & FLAG_SND_UNA_ADVANCED && !newly_lost)
2736 static void tcp_try_to_open(struct sock *sk, int flag)
2745 	if (flag & FLAG_ECE)
2876 static void tcp_process_loss(struct sock *sk, int flag, int num_dupack,
2882 	if ((flag & FLAG_SND_UNA_ADVANCED || rcu_access_pointer(tp->fastopen_rsk)) &&
2890 		if ((flag & FLAG_ORIG_SACK_ACKED) &&
2895 			if (flag & FLAG_DATA_SACKED || num_dupack)
2897 		} else if (flag & FLAG_SND_UNA_ADVANCED && !recovered) {
2922 			tcp_add_reno_sack(sk, num_dupack, flag & FLAG_ECE);
2923 		else if (flag & FLAG_SND_UNA_ADVANCED)
3007 	int fast_rexmit = 0, flag = *ack_flag;
3008 	bool ece_ack = flag & FLAG_ECE;
3009 	bool do_lost = num_dupack || ((flag & FLAG_DATA_SACKED) &&
3056 		if (!(flag & FLAG_SND_UNA_ADVANCED)) {
3067 			if (!tcp_time_to_recover(sk, flag))
3076 		tcp_process_loss(sk, flag, num_dupack, rexmit);
3087 			if (flag & FLAG_SND_UNA_ADVANCED)
3096 		if (!tcp_time_to_recover(sk, flag)) {
3097 			tcp_try_to_open(sk, flag);
3122 static void tcp_update_rtt_min(struct sock *sk, u32 rtt_us, const int flag)
3127 	if ((flag & FLAG_ACK_MAYBE_DELAYED) && rtt_us > tcp_min_rtt(tp)) {
3138 static bool tcp_ack_update_rtt(struct sock *sk, const int flag,
3159 	    tp->rx_opt.rcv_tsecr && flag & FLAG_ACKED)
3170 	tcp_update_rtt_min(sk, ca_rtt_us, flag);
3298 	int flag = 0;
3325 			flag |= FLAG_RETRANS_DATA_ACKED;
3335 				flag |= FLAG_ORIG_SACK_ACKED;
3361 			flag |= FLAG_DATA_ACKED;
3363 			flag |= FLAG_SYN_ACKED;
3390 			flag |= FLAG_SACK_RENEGING;
3393 	if (likely(first_ackt) && !(flag & FLAG_RETRANS_DATA_ACKED)) {
3400 		    !(flag & (FLAG_CA_ALERT | FLAG_SYN_ACKED))) {
3405 			flag |= FLAG_ACK_MAYBE_DELAYED;
3412 	rtt_update = tcp_ack_update_rtt(sk, flag, seq_rtt_us, sack_rtt_us,
3415 	if (flag & FLAG_ACKED) {
3416 		flag |= FLAG_SET_XMIT_TIMER;  /* set TLP or RTO timer */
3431 			if (flag & FLAG_RETRANS_DATA_ACKED)
3432 				flag &= ~FLAG_ORIG_SACK_ACKED;
3450 		flag |= FLAG_SET_XMIT_TIMER;  /* set TLP or RTO timer */
3485 	return flag;
3512 static inline bool tcp_ack_is_dubious(const struct sock *sk, const int flag)
3514 	return !(flag & FLAG_NOT_DUP) || (flag & FLAG_CA_ALERT) ||
3519 static inline bool tcp_may_raise_cwnd(const struct sock *sk, const int flag)
3529 		return flag & FLAG_FORWARD_PROGRESS;
3531 	return flag & FLAG_DATA_ACKED;
3540 			     int flag, const struct rate_sample *rs)
3545 		icsk->icsk_ca_ops->cong_control(sk, ack, flag, rs);
3551 		tcp_cwnd_reduction(sk, acked_sacked, rs->losses, flag);
3552 	} else if (tcp_may_raise_cwnd(sk, flag)) {
3632 	int flag = 0;
3639 		flag |= FLAG_WIN_UPDATE;
3663 	return flag;
3767 static void tcp_process_tlp_ack(struct sock *sk, u32 ack, int flag)
3777 	} else if (flag & FLAG_DSACK_TLP) {
3790 	} else if (!(flag & (FLAG_SND_UNA_ADVANCED |
3827 static u32 tcp_newly_delivered(struct sock *sk, u32 prior_delivered, int flag)
3835 	if (flag & FLAG_ECE)
3842 static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
3876 			if (!(flag & FLAG_NO_CHALLENGE_ACK))
3890 		flag |= FLAG_SND_UNA_ADVANCED;
3906 	if (flag & FLAG_UPDATE_TS_RECENT)
3909 	if ((flag & (FLAG_SLOWPATH | FLAG_SND_UNA_ADVANCED)) ==
3917 		flag |= FLAG_WIN_UPDATE;
3926 			flag |= FLAG_DATA;
3930 		flag |= tcp_ack_update_window(sk, skb, ack, ack_seq);
3933 			flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una,
3937 			flag |= FLAG_ECE;
3943 					    flag & FLAG_ECE);
3945 		if (flag & FLAG_WIN_UPDATE)
3970 	flag |= tcp_clean_rtx_queue(sk, skb, prior_fack, prior_snd_una,
3971 				    &sack_state, flag & FLAG_ECE);
3976 		tcp_process_tlp_ack(sk, ack, flag);
3978 	if (tcp_ack_is_dubious(sk, flag)) {
3979 		if (!(flag & (FLAG_SND_UNA_ADVANCED |
3983 			if (!(flag & FLAG_DATA))
3986 		tcp_fastretrans_alert(sk, prior_snd_una, num_dupack, &flag,
3991 	if (flag & FLAG_SET_XMIT_TIMER)
3994 	if ((flag & FLAG_FORWARD_PROGRESS) || !(flag & FLAG_NOT_DUP))
3997 	delivered = tcp_newly_delivered(sk, delivered, flag);
3999 	rs.is_ack_delayed = !!(flag & FLAG_ACK_MAYBE_DELAYED);
4001 	tcp_cong_control(sk, ack, delivered, flag, sack_state.rate);
4007 	if (flag & FLAG_DSACKING_ACK) {
4008 		tcp_fastretrans_alert(sk, prior_snd_una, num_dupack, &flag,
4010 		tcp_newly_delivered(sk, delivered, flag);
4019 		tcp_process_tlp_ack(sk, ack, flag);
4027 		flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una,
4029 		tcp_fastretrans_alert(sk, prior_snd_una, num_dupack, &flag,
4031 		tcp_newly_delivered(sk, delivered, flag);
5181 			 * because the FIN flag will simply be merged to the
6041 	 *	PSH flag is ignored.