On 5/14/25 3:56 PM, chia-yu.chang@xxxxxxxxxxxxxxxxxxx wrote:
> @@ -6450,8 +6480,12 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb,
> * RFC 5961 4.2 : Send a challenge ack
> */
> if (th->syn) {
> - if (tcp_ecn_mode_accecn(tp))
> + if (tcp_ecn_mode_accecn(tp)) {
> + u8 opt_demand = max_t(u8, 1, tp->accecn_opt_demand);
> +
> accecn_reflector = true;
> + tp->accecn_opt_demand = opt_demand;
There is similar code to update accecn_opt_demand above, possibly worth
an helper.
> @@ -1237,12 +1253,16 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb
> }
>
> if (tcp_ecn_mode_accecn(tp) &&
> - sock_net(sk)->ipv4.sysctl_tcp_ecn_option) {
> + sock_net(sk)->ipv4.sysctl_tcp_ecn_option &&
> + (sock_net(sk)->ipv4.sysctl_tcp_ecn_option >= TCP_ECN_OPTION_FULL ||
> + tp->accecn_opt_demand ||
> + tcp_accecn_option_beacon_check(sk))) {
> int saving = opts->num_sack_blocks > 0 ? 2 : 0;
> int remaining = MAX_TCP_OPTION_SPACE - size;
>
> opts->ecn_bytes = tp->received_ecn_bytes;
> - size += tcp_options_fit_accecn(opts, tp->accecn_minlen,
> + size += tcp_options_fit_accecn(opts,
> + tp->accecn_minlen,
> remaining,
> saving);
Please avoid unneeded white-space only changes.
/P
