mm/swapfile.c: use list_for_each_entry_safe in free_swap_count_continuations

Use list_for_each_entry_safe() instead of list_for_each_safe() to
simplify the code.
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/swapfile.c

@@ -2953,11 +2953,10 @@ static void free_swap_count_continuations(struct swap_info_struct *si)
 		struct page *head;
 		head = vmalloc_to_page(si->swap_map + offset);
 		if (page_private(head)) {
-			struct list_head *this, *next;
-			list_for_each_safe(this, next, &head->lru) {
-				struct page *page;
-				page = list_entry(this, struct page, lru);
-				list_del(this);
+			struct page *page, *next;
+
+			list_for_each_entry_safe(page, next, &head->lru, lru) {
+				list_del(&page->lru);
 				__free_page(page);
 			}
 		}