/proc/kpagecount: return 0 for special pages that are never mapped

Certain pages that are never mapped to userspace have a type indicated in
the page_type field of their struct pages (e.g.  PG_buddy).  page_type
overlaps with _mapcount so set the count to 0 and avoid calling
page_mapcount() for these pages.

[[email protected]: incorporate feedback from Matthew Wilcox]
  Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Anthony Yznaga <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Acked-by: Matthew Wilcox <[email protected]>
Reviewed-by: Naoya Horiguchi <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Alexander Duyck <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Miles Chen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions