[PATCH v10 20/69] mm: optimize find_exact_vma() to use vma_lookup()

[Liam Howlett]

From: "Liam R. Howlett" <Liam.Howlett at Oracle.com>

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.

Link: https://lkml.kernel.org/r/20220504011345.662299-5-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett at Oracle.com>
Reviewed-by: Vlastimil Babka <vbabka at suse.cz>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: David Howells <dhowells at redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy at infradead.org>
Cc: SeongJae Park <sj at kernel.org>
Cc: Will Deacon <will at kernel.org>
Cc: Davidlohr Bueso <dave at stgolabs.net>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
---
 include/linux/mm.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 6b84dbdb8e9f..f15301bd7f99 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2863,7 +2863,7 @@ 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;
-- 
2.35.1