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| author | Andrea Arcangeli <aarcange@redhat.com> | 2011-01-13 15:46:55 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-01-13 17:32:42 -0800 |
| commit | 0af4e98b6b095c74588af04872f83d333c958c32 (patch) | |
| tree | 56b1965482470219a8cf11b7e7c875ae91bff46e | |
| parent | f66055ab6fb9731dbfce320c5202ef4441b5d77f (diff) | |
| download | linux-stable-0af4e98b6b095c74588af04872f83d333c958c32.tar.gz linux-stable-0af4e98b6b095c74588af04872f83d333c958c32.tar.bz2 linux-stable-0af4e98b6b095c74588af04872f83d333c958c32.zip | |
thp: madvise(MADV_HUGEPAGE)
Add madvise MADV_HUGEPAGE to mark regions that are important to be
hugepage backed. Return -EINVAL if the vma is not of an anonymous type,
or the feature isn't built into the kernel. Never silently return
success.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/huge_mm.h | 6 | ||||
| -rw-r--r-- | mm/huge_memory.c | 16 | ||||
| -rw-r--r-- | mm/madvise.c | 8 |
3 files changed, 30 insertions, 0 deletions
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 9301824c7491..d9ab70d776e2 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -97,6 +97,7 @@ extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd); #if HPAGE_PMD_ORDER > MAX_ORDER #error "hugepages can't be allocated by the buddy allocator" #endif +extern int hugepage_madvise(unsigned long *vm_flags); #else /* CONFIG_TRANSPARENT_HUGEPAGE */ #define HPAGE_PMD_SHIFT ({ BUG(); 0; }) #define HPAGE_PMD_MASK ({ BUG(); 0; }) @@ -113,6 +114,11 @@ static inline int split_huge_page(struct page *page) do { } while (0) #define wait_split_huge_page(__anon_vma, __pmd) \ do { } while (0) +static inline int hugepage_madvise(unsigned long *vm_flags) +{ + BUG(); + return 0; +} #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif /* _LINUX_HUGE_MM_H */ diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 763507932898..620891f4e54f 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -896,6 +896,22 @@ out: return ret; } +int hugepage_madvise(unsigned long *vm_flags) +{ + /* + * Be somewhat over-protective like KSM for now! + */ + if (*vm_flags & (VM_HUGEPAGE | VM_SHARED | VM_MAYSHARE | + VM_PFNMAP | VM_IO | VM_DONTEXPAND | + VM_RESERVED | VM_HUGETLB | VM_INSERTPAGE | + VM_MIXEDMAP | VM_SAO)) + return -EINVAL; + + *vm_flags |= VM_HUGEPAGE; + + return 0; +} + void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd) { struct page *page; diff --git a/mm/madvise.c b/mm/madvise.c index 319528b8db74..ecde40a401c1 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -71,6 +71,11 @@ static long madvise_behavior(struct vm_area_struct * vma, if (error) goto out; break; + case MADV_HUGEPAGE: + error = hugepage_madvise(&new_flags); + if (error) + goto out; + break; } if (new_flags == vma->vm_flags) { @@ -283,6 +288,9 @@ madvise_behavior_valid(int behavior) case MADV_MERGEABLE: case MADV_UNMERGEABLE: #endif +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + case MADV_HUGEPAGE: +#endif return 1; default: |