Add a bit TCPI_OPT_SYN_DATA (32) to the socket option TCP_INFO:tcpi_options. It's set if the data in SYN (sent or received) is acked by SYN-ACK. Server or client application can use this information to check Fast Open success rate.
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| @@ -191,7 +191,8 @@ struct tcp_sock { · 190 unmodified lines | |||
| 191 | u8 do_early_retrans:1,/* Enable RFC5827 early-retransmit */ | 191 | u8 do_early_retrans:1,/* Enable RFC5827 early-retransmit */ |
| 192 | early_retrans_delayed:1, /* Delayed ER timer installed */ | 192 | early_retrans_delayed:1, /* Delayed ER timer installed */ |
| 193 | syn_data:1, /* SYN includes data */ | 193 | syn_data:1, /* SYN includes data */ |
| 194 | syn_fastopen:1; /* SYN includes Fast Open option */ | 194 | syn_fastopen:1, /* SYN includes Fast Open option */ |
| 195 | syn_data_acked:1;/* data in SYN is acked by SYN-ACK */ | ||
| 195 | 196 | ||
| 196 | /* RTT measurement */ | 197 | /* RTT measurement */ |
| 197 | u32 srtt; /* smoothed round trip time << 3 */ | 198 | u32 srtt; /* smoothed round trip time << 3 */ |