cgroup/cpuset: Avoid clearing CS_SCHED_LOAD_BALANCE twice

In cpuset_css_online(), CS_SCHED_LOAD_BALANCE will be cleared twice,
the former one in the is_in_v2_mode() case could be removed because
is_in_v2_mode() can be true for cgroup v1 if the "cpuset_v2_mode"
mount option is specified, that balance flag change isn't appropriate
for this particular case.
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

kernel/cgroup/cpuset.c

@@ -4052,11 +4052,6 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
 		cs->effective_mems = parent->effective_mems;
 		cs->use_parent_ecpus = true;
 		parent->child_ecpus_count++;
-		/*
-		 * Clear CS_SCHED_LOAD_BALANCE if parent is isolated
-		 */
-		if (!is_sched_load_balance(parent))
-			clear_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
 	}
 
 	/*