> The routine is only called once during VM initialization, so the
> result will be exactly the same either way.

pmap_free_pages is called twice during VM initialization.  Both times it is
used to size some data structure depending on the amount of free space
available.  Since after the first call the first data structure is allocated
via pmap_steal_memory actually stealing some memory from the pool of pages,
the second data structure is slightly oversized when using your code.

Hope it helps.

Ciao,
Wolfgang
--
ws@TooLs.DE     (Wolfgang Solfrank, TooLs GmbH) 	+49-228-985800