sysctl_root
sc->sysctl_root = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_hw),
sysctl_trans = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(sc->sysctl_root),
struct sysctl_oid *sysctl_root;
static int sysctl_root(SYSCTL_HANDLER_ARGS);
error = sysctl_root(0, name, namelen, &req);
error = sysctl_root(0, name, namelen, &req);
error = sysctl_root(0, name, namelen, &req);