mm/slub.c: page is always non-NULL in node_match()

node_match() is a static function and is only invoked in slub.c.

In all three places, `page' is ensured to be valid.

Link: http://lkml.kernel.org/r/20181106150245.1668-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/slub.c

@@ -2369,7 +2369,7 @@ static int slub_cpu_dead(unsigned int cpu)
 static inline int node_match(struct page *page, int node)
 {
 #ifdef CONFIG_NUMA
-	if (!page || (node != NUMA_NO_NODE && page_to_nid(page) != node))
+	if (node != NUMA_NO_NODE && page_to_nid(page) != node)
 		return 0;
 #endif
 	return 1;