mm/vmscan: make inactive_anon/file_is_low return bool

Make inactive_anon/file_is_low return bool due to these particular
functions only using either one or zero as their return value.

No functional change.

Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmscan.c

@@ -1859,7 +1859,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
 }
 
 #ifdef CONFIG_SWAP
-static int inactive_anon_is_low_global(struct zone *zone)
+static bool inactive_anon_is_low_global(struct zone *zone)
 {
 	unsigned long active, inactive;
 
@@ -1876,14 +1876,14 @@ static int inactive_anon_is_low_global(struct zone *zone)
  * Returns true if the zone does not have enough inactive anon pages,
  * meaning some active anon pages need to be deactivated.
  */
-static int inactive_anon_is_low(struct lruvec *lruvec)
+static bool inactive_anon_is_low(struct lruvec *lruvec)
 {
 	/*
 	 * If we don't have swap space, anonymous page deactivation
 	 * is pointless.
 	 */
 	if (!total_swap_pages)
-		return 0;
+		return false;
 
 	if (!mem_cgroup_disabled())
 		return mem_cgroup_inactive_anon_is_low(lruvec);
@@ -1891,9 +1891,9 @@ static int inactive_anon_is_low(struct lruvec *lruvec)
 	return inactive_anon_is_low_global(lruvec_zone(lruvec));
 }
 #else
-static inline int inactive_anon_is_low(struct lruvec *lruvec)
+static inline bool inactive_anon_is_low(struct lruvec *lruvec)
 {
-	return 0;
+	return false;
 }
 #endif
 
@@ -1911,7 +1911,7 @@ static inline int inactive_anon_is_low(struct lruvec *lruvec)
  * This uses a different ratio than the anonymous pages, because
  * the page cache uses a use-once replacement algorithm.
  */
-static int inactive_file_is_low(struct lruvec *lruvec)
+static bool inactive_file_is_low(struct lruvec *lruvec)
 {
 	unsigned long inactive;
 	unsigned long active;
@@ -1922,7 +1922,7 @@ static int inactive_file_is_low(struct lruvec *lruvec)
 	return active > inactive;
 }
 
-static int inactive_list_is_low(struct lruvec *lruvec, enum lru_list lru)
+static bool inactive_list_is_low(struct lruvec *lruvec, enum lru_list lru)
 {
 	if (is_file_lru(lru))
 		return inactive_file_is_low(lruvec);