1 files changed, 26 insertions, 16 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index bf69717325b4..72a0383f382f 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -222,7 +222,8 @@ static struct cpuset top_cpuset = {
  *
  * Walk @des_cs through the online descendants of @root_cs.  Must be used
  * with RCU read locked.  The caller may modify @pos_css by calling
- * css_rightmost_descendant() to skip subtree.
+ * css_rightmost_descendant() to skip subtree.  @root_cs is included in the
+ * iteration and the first node to be visited.
  */
 #define cpuset_for_each_descendant_pre(des_cs, pos_css, root_cs)	\
 	css_for_each_descendant_pre((pos_css), &(root_cs)->css)		\
@@ -506,6 +507,9 @@ static void update_domain_attr_tree(struct sched_domain_attr *dattr,
 
 	rcu_read_lock();
 	cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
+		if (cp == root_cs)
+			continue;
+
 		/* skip the whole subtree if @cp doesn't have any CPU */
 		if (cpumask_empty(cp->cpus_allowed)) {
 			pos_css = css_rightmost_descendant(pos_css);
@@ -613,6 +617,8 @@ static int generate_sched_domains(cpumask_var_t **domains,
 
 	rcu_read_lock();
 	cpuset_for_each_descendant_pre(cp, pos_css, &top_cpuset) {
+		if (cp == &top_cpuset)
+			continue;
 		/*
 		 * Continue traversing beyond @cp iff @cp has some CPUs and
 		 * isn't load balancing.  The former is obvious.  The
@@ -875,15 +881,17 @@ static void update_tasks_cpumask_hier(struct cpuset *root_cs,
 	struct cpuset *cp;
 	struct cgroup_subsys_state *pos_css;
 
-	if (update_root)
-		update_tasks_cpumask(root_cs, heap);
-
 	rcu_read_lock();
 	cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
-		/* skip the whole subtree if @cp have some CPU */
-		if (!cpumask_empty(cp->cpus_allowed)) {
-			pos_css = css_rightmost_descendant(pos_css);
-			continue;
+		if (cp == root_cs) {
+			if (!update_root)
+				continue;
+		} else {
+			/* skip the whole subtree if @cp have some CPU */
+			if (!cpumask_empty(cp->cpus_allowed)) {
+				pos_css = css_rightmost_descendant(pos_css);
+				continue;
+			}
 		}
 		if (!css_tryget(&cp->css))
 			continue;
@@ -1130,15 +1138,17 @@ static void update_tasks_nodemask_hier(struct cpuset *root_cs,
 	struct cpuset *cp;
 	struct cgroup_subsys_state *pos_css;
 
-	if (update_root)
-		update_tasks_nodemask(root_cs, heap);
-
 	rcu_read_lock();
 	cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
-		/* skip the whole subtree if @cp have some CPU */
-		if (!nodes_empty(cp->mems_allowed)) {
-			pos_css = css_rightmost_descendant(pos_css);
-			continue;
+		if (cp == root_cs) {
+			if (!update_root)
+				continue;
+		} else {
+			/* skip the whole subtree if @cp have some CPU */
+			if (!nodes_empty(cp->mems_allowed)) {
+				pos_css = css_rightmost_descendant(pos_css);
+				continue;
+			}
 		}
 		if (!css_tryget(&cp->css))
 			continue;
@@ -2237,7 +2247,7 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
 
 		rcu_read_lock();
 		cpuset_for_each_descendant_pre(cs, pos_css, &top_cpuset) {
-			if (!css_tryget(&cs->css))
+			if (cs == &top_cpuset || !css_tryget(&cs->css))
 				continue;
 			rcu_read_unlock();