nf_ct_expires
expires = clamp(nf_ct_expires(tmp), GC_SCAN_INTERVAL_MIN, GC_SCAN_INTERVAL_CLAMP);
timeout = nf_ct_expires(ct) / HZ;
expires = nf_ct_expires(ct);
seq_printf(s, "%ld ", nf_ct_expires(ct) / HZ);
*dest = jiffies_to_msecs(nf_ct_expires(ct));
unsigned long expires = nf_ct_expires(ct) / HZ;