[PATCH 2/4] ksm: use GET_KSM_PAGE_NOLOCK to get ksm page in remove_rmap_item_from_tree()

[Miaohe Lin]

It's unnecessary to lock the page when get ksm page if we're going to
remove the rmap item as page migration is irrelevant in this case. Use
GET_KSM_PAGE_NOLOCK instead to save some page lock cycles.

Signed-off-by: Miaohe Lin <linmia...@huawei.com>
---
 mm/ksm.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/mm/ksm.c b/mm/ksm.c
index 359afb3023b4..5650a282da3e 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -778,12 +778,11 @@ static void remove_rmap_item_from_tree(struct rmap_item 
*rmap_item)
                struct page *page;
 
                stable_node = rmap_item->head;
-               page = get_ksm_page(stable_node, GET_KSM_PAGE_LOCK);
+               page = get_ksm_page(stable_node, GET_KSM_PAGE_NOLOCK);
                if (!page)
                        goto out;
 
                hlist_del(&rmap_item->hlist);
-               unlock_page(page);
                put_page(page);
 
                if (!hlist_empty(&stable_node->hlist))
-- 
2.19.1