TCP_SYN_RETRIES    19 net/dccp/timer.c int  sysctl_dccp_request_retries	__read_mostly = TCP_SYN_RETRIES;
TCP_SYN_RETRIES    24 net/ipv4/tcp_timer.c int sysctl_tcp_syn_retries __read_mostly = TCP_SYN_RETRIES;