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 9d97a3579de8c9a6a9aa0b79ae393d114bc4b29d..cb9f16ca62c02b6bd3fed9307c374c4d570bbcac 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2883,7 +2883,7 @@ 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;