From: z00281421 <z00281421@xxxxxxxxxxxxxxxxxxxx>
more mapcount page as kpage could reduce total replacement times
than fewer mapcount one when ksmd scan and replace among
forked pages later.
Signed-off-by: z00281421 <z00281421@xxxxxxxxxxxxxxxxxxxx>
---
mm/ksm.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/mm/ksm.c b/mm/ksm.c
index 4786b41..4d530af 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1094,6 +1094,14 @@ static struct page *try_to_merge_two_pages(struct rmap_item *rmap_item,
{
int err;
+ /*
+ * select more mapcount page as kpage
+ */
+ if (page_mapcount(page) < page_mapcount(tree_page)) {
+ swap(page, tree_page);
+ swap(rmap_item, tree_rmap_item);
+ }
+
err = try_to_merge_with_ksm_page(rmap_item, page, NULL);
if (!err) {
err = try_to_merge_with_ksm_page(tree_rmap_item,