diff options
author | Mel Gorman <mel@csn.ul.ie> | 2010-05-24 14:32:21 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-25 08:06:59 -0700 |
commit | e9e96b39f932a065e14f5d5bab0797ae261d03b5 (patch) | |
tree | 1164a4bf40c34715944b47da035ba823f1d8b60a | |
parent | 3fe2011ff51e92500010a495df4be86745fbbda9 (diff) |
mm: allow CONFIG_MIGRATION to be set without CONFIG_NUMA or memory hot-remove
CONFIG_MIGRATION currently depends on CONFIG_NUMA or on the architecture
being able to hot-remove memory. The main users of page migration such as
sys_move_pages(), sys_migrate_pages() and cpuset process migration are
only beneficial on NUMA so it makes sense.
As memory compaction will operate within a zone and is useful on both NUMA
and non-NUMA systems, this patch allows CONFIG_MIGRATION to be set if the
user selects CONFIG_COMPACTION as an option.
[akpm@linux-foundation.org: Depend on CONFIG_HUGETLB_PAGE]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | mm/Kconfig | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index 9c61158308d..527136b2238 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -172,6 +172,15 @@ config SPLIT_PTLOCK_CPUS default "4" # +# support for memory compaction +config COMPACTION + bool "Allow for memory compaction" + select MIGRATION + depends on EXPERIMENTAL && HUGETLB_PAGE && MMU + help + Allows the compaction of memory for the allocation of huge pages. + +# # support for page migration # config MIGRATION @@ -180,9 +189,11 @@ config MIGRATION depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE help Allows the migration of the physical location of pages of processes - while the virtual addresses are not changed. This is useful for - example on NUMA systems to put pages nearer to the processors accessing - the page. + while the virtual addresses are not changed. This is useful in + two situations. The first is on NUMA systems to put pages nearer + to the processors accessing. The second is when allocating huge + pages as migration can relocate pages to satisfy a huge page + allocation instead of reclaiming. config PHYS_ADDR_T_64BIT def_bool 64BIT || ARCH_PHYS_ADDR_T_64BIT |