pf_state_key_ref
st->key[idx] = pf_state_key_ref(sk); /* give a ref to state */
sk2 = pf_state_key_ref(sk1);
sks = pf_state_key_ref(skw);
sks = pf_state_key_ref(skw);
sk = pf_state_key_ref(inp->inp_pf_sk);
struct pf_state_key *pf_state_key_ref(struct pf_state_key *);
pf_state_key_ref(skrev);
pf_state_key_ref(sk);
m->m_pkthdr.pf.statekey = pf_state_key_ref(sk);
inp->inp_pf_sk = pf_state_key_ref(sk);