mm: Optimize find_exact_vma() to use vma_lookup()

Use vma_lookup() to walk the tree to the start value requested.  If
the vma at the start does not match, then the answer is NULL and there
is no need to look at the next vma the way that find_vma() would.

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3f5c1494cda00480121562be2ff81b7e27a600ef..9a3972fedeec1f28b02759f85425525d18eb4471 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2829,7 +2829,7 @@ static inline unsigned long vma_pages(struct vm_area_struct *vma)
 static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
                                unsigned long vm_start, unsigned long vm_end)
 {
-       struct vm_area_struct *vma = find_vma(mm, vm_start);
+       struct vm_area_struct *vma = vma_lookup(mm, vm_start);
 
        if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
                vma = NULL;