cpuset: move update_domain_attr_tree to cpuset_v1.c

Since relax_domain_level is only applicable to v1, move
update_domain_attr_tree() to cpuset-v1.c, which solely updates
relax_domain_level,

Additionally, relax_domain_level is now initialized in cpuset1_inited.
Accordingly, the initialization of relax_domain_level in top_cpuset is
removed. The unnecessary remote_partition initialization in top_cpuset
is also cleaned up.

As a result, relax_domain_level can be defined in cpuset only when
CONFIG_CPUSETS_V1=y.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Author: Chen Ridong

kernel/cgroup/cpuset-internal.h

@@ -150,9 +150,6 @@ struct cpuset {
 	 */
 	int attach_in_progress;
 
-	/* for custom sched domain */
-	int relax_domain_level;
-
 	/* partition root state */
 	int partition_root_state;
 
@@ -182,6 +179,9 @@ struct cpuset {
 
 #ifdef CONFIG_CPUSETS_V1
 	struct fmeter fmeter;		/* memory_pressure filter */
+
+	/* for custom sched domain */
+	int relax_domain_level;
 #endif
 };
 
@@ -296,6 +296,8 @@ void cpuset1_hotplug_update_tasks(struct cpuset *cs,
 int cpuset1_validate_change(struct cpuset *cur, struct cpuset *trial);
 void cpuset1_init(struct cpuset *cs);
 void cpuset1_online_css(struct cgroup_subsys_state *css);
+void update_domain_attr_tree(struct sched_domain_attr *dattr,
+				    struct cpuset *root_cs);
 #else
 static inline void cpuset1_update_task_spread_flags(struct cpuset *cs,
 					struct task_struct *tsk) {}
@@ -307,6 +309,9 @@ static inline int cpuset1_validate_change(struct cpuset *cur,
 				struct cpuset *trial) { return 0; }
 static inline void cpuset1_init(struct cpuset *cs) {}
 static inline void cpuset1_online_css(struct cgroup_subsys_state *css) {}
+static inline void update_domain_attr_tree(struct sched_domain_attr *dattr,
+				    struct cpuset *root_cs) {}
+
 #endif /* CONFIG_CPUSETS_V1 */
 
 #endif /* __CPUSET_INTERNAL_H */

kernel/cgroup/cpuset-v1.c

@@ -502,6 +502,7 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft,
 void cpuset1_init(struct cpuset *cs)
 {
 	fmeter_init(&cs->fmeter);
+	cs->relax_domain_level = -1;
 }
 
 void cpuset1_online_css(struct cgroup_subsys_state *css)
@@ -552,6 +553,33 @@ void cpuset1_online_css(struct cgroup_subsys_state *css)
 	cpuset_callback_unlock_irq();
 }
 
+static void
+update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c)
+{
+	if (dattr->relax_domain_level < c->relax_domain_level)
+		dattr->relax_domain_level = c->relax_domain_level;
+}
+
+void update_domain_attr_tree(struct sched_domain_attr *dattr,
+				    struct cpuset *root_cs)
+{
+	struct cpuset *cp;
+	struct cgroup_subsys_state *pos_css;
+
+	rcu_read_lock();
+	cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
+		/* skip the whole subtree if @cp doesn't have any CPU */
+		if (cpumask_empty(cp->cpus_allowed)) {
+			pos_css = css_rightmost_descendant(pos_css);
+			continue;
+		}
+
+		if (is_sched_load_balance(cp))
+			update_domain_attr(dattr, cp);
+	}
+	rcu_read_unlock();
+}
+
 /*
  * for the common functions, 'private' gives the type of file
  */

kernel/cgroup/cpuset.c

@@ -215,8 +215,6 @@ static struct cpuset top_cpuset = {
 	.flags = BIT(CS_CPU_EXCLUSIVE) |
 		 BIT(CS_MEM_EXCLUSIVE) | BIT(CS_SCHED_LOAD_BALANCE),
 	.partition_root_state = PRS_ROOT,
-	.relax_domain_level = -1,
-	.remote_partition = false,
 };
 
 /*
@@ -755,34 +753,6 @@ static int cpusets_overlap(struct cpuset *a, struct cpuset *b)
 	return cpumask_intersects(a->effective_cpus, b->effective_cpus);
 }
 
-static void
-update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c)
-{
-	if (dattr->relax_domain_level < c->relax_domain_level)
-		dattr->relax_domain_level = c->relax_domain_level;
-	return;
-}
-
-static void update_domain_attr_tree(struct sched_domain_attr *dattr,
-				    struct cpuset *root_cs)
-{
-	struct cpuset *cp;
-	struct cgroup_subsys_state *pos_css;
-
-	rcu_read_lock();
-	cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
-		/* skip the whole subtree if @cp doesn't have any CPU */
-		if (cpumask_empty(cp->cpus_allowed)) {
-			pos_css = css_rightmost_descendant(pos_css);
-			continue;
-		}
-
-		if (is_sched_load_balance(cp))
-			update_domain_attr(dattr, cp);
-	}
-	rcu_read_unlock();
-}
-
 /* Must be called with cpuset_mutex held.  */
 static inline int nr_cpusets(void)
 {
@@ -3603,7 +3573,6 @@ cpuset_css_alloc(struct cgroup_subsys_state *parent_css)
 
 	__set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
 	cpuset1_init(cs);
-	cs->relax_domain_level = -1;
 
 	/* Set CS_MEMORY_MIGRATE for default hierarchy */
 	if (cpuset_v2())