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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 /mm/huge_memory.c | |
| parent | f66055ab6fb9731dbfce320c5202ef4441b5d77f (diff) | |
| download | lwn-0af4e98b6b095c74588af04872f83d333c958c32.tar.gz lwn-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>
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 16 |
1 files changed, 16 insertions, 0 deletions
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; |