mm/buddy: cleanup on should_fail_alloc_page

Currently, function should_fail() has "bool" for its return value, so it's
reasonable to change the return value of function should_fail_alloc_page()
into "bool" as well.

The patch does cleanup on function should_fail_alloc_page() to have "bool"
for its return value.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -1529,16 +1529,16 @@ static int __init setup_fail_page_alloc(char *str)
 }
 __setup("fail_page_alloc=", setup_fail_page_alloc);
 
-static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
+static bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
 {
 	if (order < fail_page_alloc.min_order)
-		return 0;
+		return false;
 	if (gfp_mask & __GFP_NOFAIL)
-		return 0;
+		return false;
 	if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
-		return 0;
+		return false;
 	if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT))
-		return 0;
+		return false;
 
 	return should_fail(&fail_page_alloc.attr, 1 << order);
 }
@@ -1578,9 +1578,9 @@ late_initcall(fail_page_alloc_debugfs);
 
 #else /* CONFIG_FAIL_PAGE_ALLOC */
 
-static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
+static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
 {
-	return 0;
+	return false;
 }
 
 #endif /* CONFIG_FAIL_PAGE_ALLOC */