CONN_ACTIVE
active = (flags & (CONN_ACTIVE | CONN_EXPIRE)) == CONN_ACTIVE;
KASSERT((atomic_load_relaxed(&con->c_flags) & CONN_ACTIVE) == 0);
if ((flags & (CONN_ACTIVE | CONN_EXPIRE)) == 0) {
atomic_or_uint(&con->c_flags, CONN_ACTIVE);
if ((flags & (CONN_ACTIVE|CONN_EXPIRE)) != CONN_ACTIVE) {
flags &= PFIL_ALL | CONN_ACTIVE | CONN_PASS;