oom: fix zone_scan_mutex name

zone_scan_mutex is actually a spinlock, so name it appropriately.
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/oom_kill.c

@@ -31,7 +31,7 @@
 int sysctl_panic_on_oom;
 int sysctl_oom_kill_allocating_task;
 int sysctl_oom_dump_tasks;
-static DEFINE_SPINLOCK(zone_scan_mutex);
+static DEFINE_SPINLOCK(zone_scan_lock);
 /* #define DEBUG */
 
 /**
@@ -470,7 +470,7 @@ int try_set_zone_oom(struct zonelist *zonelist, gfp_t gfp_mask)
 	struct zone *zone;
 	int ret = 1;
 
-	spin_lock(&zone_scan_mutex);
+	spin_lock(&zone_scan_lock);
 	for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) {
 		if (zone_is_oom_locked(zone)) {
 			ret = 0;
@@ -480,7 +480,7 @@ int try_set_zone_oom(struct zonelist *zonelist, gfp_t gfp_mask)
 
 	for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) {
 		/*
-		 * Lock each zone in the zonelist under zone_scan_mutex so a
+		 * Lock each zone in the zonelist under zone_scan_lock so a
 		 * parallel invocation of try_set_zone_oom() doesn't succeed
 		 * when it shouldn't.
 		 */
@@ -488,7 +488,7 @@ int try_set_zone_oom(struct zonelist *zonelist, gfp_t gfp_mask)
 	}
 
 out:
-	spin_unlock(&zone_scan_mutex);
+	spin_unlock(&zone_scan_lock);
 	return ret;
 }
 
@@ -502,11 +502,11 @@ void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask)
 	struct zoneref *z;
 	struct zone *zone;
 
-	spin_lock(&zone_scan_mutex);
+	spin_lock(&zone_scan_lock);
 	for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) {
 		zone_clear_flag(zone, ZONE_OOM_LOCKED);
 	}
-	spin_unlock(&zone_scan_mutex);
+	spin_unlock(&zone_scan_lock);
 }
 
 /*