ksm: use GET_KSM_PAGE_NOLOCK to get ksm page in remove_rmap_item_from…

…_tree() 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. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Miaohe Lin <[email protected]> Cc: Hugh Dickins <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
kawasaki · May 5, 2021 · 3e96b6a · 3e96b6a
1 parent a08e1e1
commit 3e96b6a
Showing 1 changed file with 1 addition and 2 deletions.
diff --git 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))