cpuset: a bit cleanup for scan_for_empty_cpusets()

clean up hierarchy traversal code

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 5 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 91cf85b36dd5..3624dc0e95ed 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1833,24 +1833,21 @@ static void remove_tasks_in_empty_cpuset(struct cpuset *cs)
  */
 static void scan_for_empty_cpusets(const struct cpuset *root)
 {
+        LIST_HEAD(queue);
         struct cpuset *cp;      /* scans cpusets being updated */
         struct cpuset *child;   /* scans child cpusets of cp */
-        struct list_head queue;
         struct cgroup *cont;
         nodemask_t oldmems;
 
-        INIT_LIST_HEAD(&queue);
-
         list_add_tail((struct list_head *)&root->stack_list, &queue);
 
         while (!list_empty(&queue)) {
-                cp = container_of(queue.next, struct cpuset, stack_list);
+                cp = list_first_entry(&queue, struct cpuset, stack_list);
                 list_del(queue.next);
                 list_for_each_entry(cont, &cp->css.cgroup->children, sibling) {
                         child = cgroup_cs(cont);
                         list_add_tail(&child->stack_list, &queue);
                 }
-                cont = cp->css.cgroup;
 
                 /* Continue past cpusets with all cpus, mems online */
                 if (cpus_subset(cp->cpus_allowed, cpu_online_map) &&