Profiling a PostgreSQL function if I use

explain (analyze true, verbose true, costs true, buffers true)
select * from mystoredprocedurefunction(arg1, arg2);


I do not get any information about what the server is actually doing inside my sp.  Instead I get 5 rows describing that I invoked a function and that it took a long time.  How do I look into my stored procedure and see what is going on?  I have something very inefficient occurring.
Look into the module auto-explain.

We had a very similar question some time ago, it should be of help:
Postgres query plan of a UDF invocation written in pgpsql