ksm: use find_mergeable_vma in try_to_merge_with_ksm_page

Doing the VM_MERGEABLE check after the page == kpage check won't provide any meaningful benefit. The !vma->anon_vma check of find_mergeable_vma is the only superfluous bit in using find_mergeable_vma because the !PageAnon check of try_to_merge_one_page() implicitly checks for that, but it still looks cleaner to share the same find_mergeable_vma(). Signed-off-by: Andrea Arcangeli <[email protected]> Acked-by: Hugh Dickins <[email protected]> Cc: Petr Holasek <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
josf · Nov 6, 2015 · 85c6e8d · 85c6e8d
1 parent 98666f8
commit 85c6e8d
Showing 1 changed file with 2 additions and 6 deletions.
diff --git a/mm/ksm.c b/mm/ksm.c
@@ -1021,8 +1021,6 @@ static int try_to_merge_one_page(struct vm_area_struct *vma,
 	if (page == kpage)			/* ksm page forked */
 		return 0;
 
-	if (!(vma->vm_flags & VM_MERGEABLE))
-		goto out;
 	if (PageTransCompound(page) && page_trans_compound_anon_split(page))
 		goto out;
 	BUG_ON(PageTransCompound(page));
@@ -1087,10 +1085,8 @@ static int try_to_merge_with_ksm_page(struct rmap_item *rmap_item,
 	int err = -EFAULT;
 
 	down_read(&mm->mmap_sem);
-	if (ksm_test_exit(mm))
-		goto out;
-	vma = find_vma(mm, rmap_item->address);
-	if (!vma || vma->vm_start > rmap_item->address)
+	vma = find_mergeable_vma(mm, rmap_item->address);
+	if (!vma)
 		goto out;
 
 	err = try_to_merge_one_page(vma, page, kpage);