mm/page_alloc.c: cleanups

- make pageflag_names[] const

- remove null termination of pageflag_names[]

Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -5938,7 +5938,7 @@ bool is_free_buddy_page(struct page *page)
 }
 #endif
 
-static struct trace_print_flags pageflag_names[] = {
+static const struct trace_print_flags pageflag_names[] = {
 	{1UL << PG_locked,		"locked"	},
 	{1UL << PG_error,		"error"		},
 	{1UL << PG_referenced,		"referenced"	},
@@ -5976,7 +5976,6 @@ static struct trace_print_flags pageflag_names[] = {
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 	{1UL << PG_compound_lock,	"compound_lock"	},
 #endif
-	{-1UL,				NULL		},
 };
 
 static void dump_page_flags(unsigned long flags)
@@ -5985,14 +5984,14 @@ static void dump_page_flags(unsigned long flags)
 	unsigned long mask;
 	int i;
 
-	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) - 1 != __NR_PAGEFLAGS);
+	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS);
 
 	printk(KERN_ALERT "page flags: %#lx(", flags);
 
 	/* remove zone id */
 	flags &= (1UL << NR_PAGEFLAGS) - 1;
 
-	for (i = 0; pageflag_names[i].name && flags; i++) {
+	for (i = 0; i < ARRAY_SIZE(pageflag_names) && flags; i++) {
 
 		mask = pageflag_names[i].mask;
 		if ((flags & mask) != mask)