serialize_integer (m, si->rings[SRP_RING_OUTER].hw_if_index, sizeof (u32));
serialize_integer (m, si->rings[SRP_RING_INNER].hw_if_index, sizeof (u32));
serialize_integer (m, si->rings[SRP_RING_OUTER].hw_if_index, sizeof (u32));
serialize_integer (m, si->rings[SRP_RING_INNER].hw_if_index, sizeof (u32));