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| author | Mel Gorman <mel@csn.ul.ie> | 2007-07-17 04:03:13 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-17 10:22:59 -0700 |
| commit | 396faf0303d273219db5d7eb4a2879ad977ed185 (patch) | |
| tree | 96cb64fd6713ef7a924f4f878e259aea781f079a /include/linux/hugetlb.h | |
| parent | 2a1e274acf0b1c192face19a4be7c12d4503eaaf (diff) | |
| download | linux-396faf0303d273219db5d7eb4a2879ad977ed185.tar.gz linux-396faf0303d273219db5d7eb4a2879ad977ed185.tar.bz2 linux-396faf0303d273219db5d7eb4a2879ad977ed185.zip | |
Allow huge page allocations to use GFP_HIGH_MOVABLE
Huge pages are not movable so are not allocated from ZONE_MOVABLE. However,
as ZONE_MOVABLE will always have pages that can be migrated or reclaimed, it
can be used to satisfy hugepage allocations even when the system has been
running a long time. This allows an administrator to resize the hugepage pool
at runtime depending on the size of ZONE_MOVABLE.
This patch adds a new sysctl called hugepages_treat_as_movable. When a
non-zero value is written to it, future allocations for the huge page pool
will use ZONE_MOVABLE. Despite huge pages being non-movable, we do not
introduce additional external fragmentation of note as huge pages are always
the largest contiguous block we care about.
[akpm@linux-foundation.org: various fixes]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/hugetlb.h')
| -rw-r--r-- | include/linux/hugetlb.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 2c13715e9dde..49b7053043ad 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -15,6 +15,7 @@ static inline int is_vm_hugetlb_page(struct vm_area_struct *vma) } int hugetlb_sysctl_handler(struct ctl_table *, int, struct file *, void __user *, size_t *, loff_t *); +int hugetlb_treat_movable_handler(struct ctl_table *, int, struct file *, void __user *, size_t *, loff_t *); int copy_hugetlb_page_range(struct mm_struct *, struct mm_struct *, struct vm_area_struct *); int follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *, struct page **, struct vm_area_struct **, unsigned long *, int *, int); void unmap_hugepage_range(struct vm_area_struct *, unsigned long, unsigned long); @@ -29,6 +30,7 @@ int hugetlb_reserve_pages(struct inode *inode, long from, long to); void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed); extern unsigned long max_huge_pages; +extern unsigned long hugepages_treat_as_movable; extern const unsigned long hugetlb_zero, hugetlb_infinity; extern int sysctl_hugetlb_shm_group; |