mm: vmscan: remove noinline_for_stack

The noinline_for_stack is introduced by commit 6663562 ("vmscan: set
up pagevec as late as possible in shrink_inactive_list()"), its purpose is
to delay the allocation of pagevec as late as possible to save stack
memory.  But the commit 2bcf887 ("mm: take pagevecs off reclaim
stack") replace pagevecs by lists of pages_to_free.  So we do not need
noinline_for_stack, just remove it (let the compiler decide whether to
inline).

Link: https://lkml.kernel.org/r/20210417043538.9793-9-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Author: Muchun Song

mm/vmscan.c

@@ -2015,8 +2015,8 @@ static int too_many_isolated(struct pglist_data *pgdat, int file,
  *
  * Returns the number of pages moved to the given lruvec.
  */
-static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
-						     struct list_head *list)
+static unsigned int move_pages_to_lru(struct lruvec *lruvec,
+				      struct list_head *list)
 {
 	int nr_pages, nr_moved = 0;
 	LIST_HEAD(pages_to_free);
@@ -2096,7 +2096,7 @@ static int current_may_throttle(void)
  * shrink_inactive_list() is a helper for shrink_node().  It returns the number
  * of reclaimed pages
  */
-static noinline_for_stack unsigned long
+static unsigned long
 shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 		     struct scan_control *sc, enum lru_list lru)
 {