16 /* * struct psref_target * * Bookkeeping for an object to which users can acquire passive * references. This is compact so that it can easily be embedded * into many multitudes of objects, e.g. IP packet flows. * * prt_draining is false on initialization, and may be written * only once, to make it true, when someone has prevented new * references from being created and wants to drain the target in * order to destroy it. */