diff options
| author | Andrea Arcangeli <aarcange@redhat.com> | 2011-01-13 15:47:17 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-01-13 17:32:47 -0800 |
| commit | a664b2d8555c659127bf8fe049a58449d394a707 (patch) | |
| tree | 14771f4ab93a9dda98174f21e0361a77e2aebfa6 /mm/huge_memory.c | |
| parent | 1ddd6db43a08cba56c7ee920800980862086f1c3 (diff) | |
| download | lwn-a664b2d8555c659127bf8fe049a58449d394a707.tar.gz lwn-a664b2d8555c659127bf8fe049a58449d394a707.zip | |
thp: madvise(MADV_NOHUGEPAGE)
Add madvise MADV_NOHUGEPAGE to mark regions that are not 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>
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 | 41 |
1 files changed, 30 insertions, 11 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index f4f6041176a4..fce667c0281d 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -16,6 +16,7 @@ #include <linux/kthread.h> #include <linux/khugepaged.h> #include <linux/freezer.h> +#include <linux/mman.h> #include <asm/tlb.h> #include <asm/pgalloc.h> #include "internal.h" @@ -1388,18 +1389,36 @@ out: return ret; } -int hugepage_madvise(unsigned long *vm_flags) +int hugepage_madvise(unsigned long *vm_flags, int advice) { - /* - * 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; + switch (advice) { + case MADV_HUGEPAGE: + /* + * 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_NOHUGEPAGE; + *vm_flags |= VM_HUGEPAGE; + break; + case MADV_NOHUGEPAGE: + /* + * Be somewhat over-protective like KSM for now! + */ + if (*vm_flags & (VM_NOHUGEPAGE | + 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; + *vm_flags |= VM_NOHUGEPAGE; + break; + } return 0; } |