sysctl_tcp_keepalive_intvl 127 include/net/netns/ipv4.h int sysctl_tcp_keepalive_intvl; sysctl_tcp_keepalive_intvl 1428 include/net/tcp.h return tp->keepalive_intvl ? : net->ipv4.sysctl_tcp_keepalive_intvl; sysctl_tcp_keepalive_intvl 900 net/ipv4/sysctl_net_ipv4.c .data = &init_net.ipv4.sysctl_tcp_keepalive_intvl, sysctl_tcp_keepalive_intvl 2668 net/ipv4/tcp_ipv4.c net->ipv4.sysctl_tcp_keepalive_intvl = TCP_KEEPALIVE_INTVL;