Memory hotplug has a subtle race problem so this patchset fixes the problem
(Look at [3/3] for detail and please confirm the problem before review
other patches in this series.)

 [1/4] is just clean up and help for [2/4].
 [2/4] keeps the migratetype information to freed page's index field
       and [3/4] uses the information.
 [3/4] fixes the race problem with [2/4]'s information.
 [4/4] enhance memory-hotremove operation success ratio

After applying [2/4], migratetype argument in __free_one_page
and free_one_page is redundant so we can remove it but I decide
to not touch them because it increases code size about 50 byte.

This patchset is based on mmotm-2012-09-06-16-46

Minchan Kim (4):
  use get_page_migratetype instead of page_private
  mm: remain migratetype in freed page
  memory-hotplug: bug fix race between isolation and allocation
  memory-hotplug: fix pages missed by race rather than failing

 include/linux/mm.h             |   12 ++++++++++++
 include/linux/page-isolation.h |    4 ++++
 mm/page_alloc.c                |   19 ++++++++++++-------
 mm/page_isolation.c            |   18 ++++++++++++++++--
 4 files changed, 44 insertions(+), 9 deletions(-)

-- 
1.7.9.5