like pg_shmem_allocations, but fine-grained for DSM registry ?

I’ve been working with the DSM registry API.
I was wondering if it is possible (it doesn’t look like it) or if it has been discussed:
can we expose a view like pg_shmem_allocations, but fine-grained for every named segment (i.e. created by GetNamedDSMSegment )?

Currently, there is a "DSM Registry Data” entry in that view,
but iiuc, it’s only about the top-level hash table the registry uses.

That’s probably related to http://postgr.es/m/CAH2L28vHzRankszhqz7deXURxKncxfirnuW68zD7+hVAqaS5GQ@mail.gmail.com