From: z00281421 <[email protected]> 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 <[email protected]> --- mm/ksm.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/mm/ksm.c b/mm/ksm.c index 4786b41..17a238c 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -1094,6 +1094,21 @@ 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)) { + struct page *tmp_page; + struct rmap_item *tmp_rmap_item; + + tmp_page = page; + page = tree_page; + tree_page = tmp_page; + tmp_rmap_item = rmap_item; + rmap_item = tree_rmap_item; + tree_rmap_item = tmp_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, -- 1.7.9.5
