1ffd177deSYuchung Cheng #ifndef _TCP_DCTCP_H
2ffd177deSYuchung Cheng #define _TCP_DCTCP_H
3ffd177deSYuchung Cheng
dctcp_ece_ack_cwr(struct sock * sk,u32 ce_state)4ffd177deSYuchung Cheng static inline void dctcp_ece_ack_cwr(struct sock *sk, u32 ce_state)
5ffd177deSYuchung Cheng {
6ffd177deSYuchung Cheng struct tcp_sock *tp = tcp_sk(sk);
7ffd177deSYuchung Cheng
8ffd177deSYuchung Cheng if (ce_state == 1)
9ffd177deSYuchung Cheng tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
10ffd177deSYuchung Cheng else
11ffd177deSYuchung Cheng tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
12ffd177deSYuchung Cheng }
13ffd177deSYuchung Cheng
14ffd177deSYuchung Cheng /* Minimal DCTP CE state machine:
15ffd177deSYuchung Cheng *
16ffd177deSYuchung Cheng * S: 0 <- last pkt was non-CE
17ffd177deSYuchung Cheng * 1 <- last pkt was CE
18ffd177deSYuchung Cheng */
dctcp_ece_ack_update(struct sock * sk,enum tcp_ca_event evt,u32 * prior_rcv_nxt,u32 * ce_state)19ffd177deSYuchung Cheng static inline void dctcp_ece_ack_update(struct sock *sk, enum tcp_ca_event evt,
20ffd177deSYuchung Cheng u32 *prior_rcv_nxt, u32 *ce_state)
21ffd177deSYuchung Cheng {
22ffd177deSYuchung Cheng u32 new_ce_state = (evt == CA_EVENT_ECN_IS_CE) ? 1 : 0;
23ffd177deSYuchung Cheng
24ffd177deSYuchung Cheng if (*ce_state != new_ce_state) {
25ffd177deSYuchung Cheng /* CE state has changed, force an immediate ACK to
26ffd177deSYuchung Cheng * reflect the new CE state. If an ACK was delayed,
27ffd177deSYuchung Cheng * send that first to reflect the prior CE state.
28ffd177deSYuchung Cheng */
29ffd177deSYuchung Cheng if (inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
30ffd177deSYuchung Cheng dctcp_ece_ack_cwr(sk, *ce_state);
31ffd177deSYuchung Cheng __tcp_send_ack(sk, *prior_rcv_nxt);
32ffd177deSYuchung Cheng }
33ffd177deSYuchung Cheng inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW;
34ffd177deSYuchung Cheng }
35ffd177deSYuchung Cheng *prior_rcv_nxt = tcp_sk(sk)->rcv_nxt;
36ffd177deSYuchung Cheng *ce_state = new_ce_state;
37ffd177deSYuchung Cheng dctcp_ece_ack_cwr(sk, new_ce_state);
38ffd177deSYuchung Cheng }
39ffd177deSYuchung Cheng
40ffd177deSYuchung Cheng #endif
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