pf_state_compare_rkey
static __inline int pf_state_compare_rkey(struct pf_state_key *,
RB_GENERATE(pf_state_rtree, pf_state_key, entry, pf_state_compare_rkey);
RB_PROTOTYPE(pf_state_rtree, pf_state_key, entry, pf_state_compare_rkey);