numa: make "nr_online_nodes" unsigned int

Number of online NUMA nodes can't be negative as well.  This doesn't
save space as the variable is used only in 32-bit context, but do it
anyway for consistency.

Link: http://lkml.kernel.org/r/20190201223151.GB15820@avx2Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/nodemask.h

@@ -445,7 +445,7 @@ static inline int next_memory_node(int nid)
 }
 
 extern unsigned int nr_node_ids;
-extern int nr_online_nodes;
+extern unsigned int nr_online_nodes;
 
 static inline void node_set_online(int nid)
 {
@@ -486,7 +486,7 @@ static inline int num_node_state(enum node_states state)
 #define first_memory_node	0
 #define next_online_node(nid)	(MAX_NUMNODES)
 #define nr_node_ids		1U
-#define nr_online_nodes		1
+#define nr_online_nodes		1U
 
 #define node_set_online(node)	   node_set_state((node), N_ONLINE)
 #define node_set_offline(node)	   node_clear_state((node), N_ONLINE)

mm/page_alloc.c

@@ -290,7 +290,7 @@ EXPORT_SYMBOL(movable_zone);
 
 #if MAX_NUMNODES > 1
 unsigned int nr_node_ids __read_mostly = MAX_NUMNODES;
-int nr_online_nodes __read_mostly = 1;
+unsigned int nr_online_nodes __read_mostly = 1;
 EXPORT_SYMBOL(nr_node_ids);
 EXPORT_SYMBOL(nr_online_nodes);
 #endif
@@ -5664,7 +5664,7 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
 	else
 		page_group_by_mobility_disabled = 0;
 
-	pr_info("Built %i zonelists, mobility grouping %s.  Total pages: %ld\n",
+	pr_info("Built %u zonelists, mobility grouping %s.  Total pages: %ld\n",
 		nr_online_nodes,
 		page_group_by_mobility_disabled ? "off" : "on",
 		vm_total_pages);