Bartlomiej Zolnierkiewicz [off-list ref] writes:

Free pages belonging to Contiguous Memory Allocator (CMA) areas cannot be
used by unmovable allocations and this fact should be accounted for while
doing zone watermark checking.  Additionaly while CMA pages are isolated
they shouldn't be included in the total number of free pages (as they
cannot be allocated while they are isolated).  The following patch series
should fix both issues.  It is based on top of recent Minchan's CMA series
(https://lkml.org/lkml/2012/8/14/81 "[RFC 0/2] Reduce alloc_contig_range
latency").

v2:
- no need to call get_pageblock_migratetype() in free_one_page() in patch #1
  (thanks to review from Michal Nazarewicz)
- fix issues pointed in http://www.spinics.net/lists/linux-mm/msg41017.html
  in patch #2 (ditto)
- remove no longer needed is_cma_pageblock() from patch #2

I'm not an expert on watermarks but the code of the whole patchset looks
good to me.

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.o. | Liege of Serenely Enlightened Majesty of      o' \,=./ `o
..o | Computer Science,  Michał “mina86” Nazarewicz    (o o)
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