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| author | Michal Nazarewicz <mina86@mina86.com> | 2011-12-29 13:09:50 +0100 |
|---|---|---|
| committer | Marek Szyprowski <m.szyprowski@samsung.com> | 2012-05-21 15:09:32 +0200 |
| commit | 47118af076f64844b4f423bc2f545b2da9dab50d (patch) | |
| tree | 00df88cf2f60a2a3efc1a6c46ad88d128aee2071 /mm/Kconfig | |
| parent | 6d4a49160de2c684fb59fa627bce80e200224331 (diff) | |
| download | lwn-47118af076f64844b4f423bc2f545b2da9dab50d.tar.gz lwn-47118af076f64844b4f423bc2f545b2da9dab50d.zip | |
mm: mmzone: MIGRATE_CMA migration type added
The MIGRATE_CMA migration type has two main characteristics:
(i) only movable pages can be allocated from MIGRATE_CMA
pageblocks and (ii) page allocator will never change migration
type of MIGRATE_CMA pageblocks.
This guarantees (to some degree) that page in a MIGRATE_CMA page
block can always be migrated somewhere else (unless there's no
memory left in the system).
It is designed to be used for allocating big chunks (eg. 10MiB)
of physically contiguous memory. Once driver requests
contiguous memory, pages from MIGRATE_CMA pageblocks may be
migrated away to create a contiguous block.
To minimise number of migrations, MIGRATE_CMA migration type
is the last type tried when page allocator falls back to other
migration types when requested.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Rob Clark <rob.clark@linaro.org>
Tested-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Robert Nelson <robertcnelson@gmail.com>
Tested-by: Barry Song <Baohua.Song@csr.com>
Diffstat (limited to 'mm/Kconfig')
| -rw-r--r-- | mm/Kconfig | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index e338407f1225..39220026c797 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -198,7 +198,7 @@ config COMPACTION config MIGRATION bool "Page migration" def_bool y - depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION + depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION || CMA help Allows the migration of the physical location of pages of processes while the virtual addresses are not changed. This is useful in |