diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index 2e65e4c4d6e7585a58f6af0e943cb258eb771647..edb45e2f7f542e2c707b46aae9868540d9df10de 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -226,6 +226,8 @@ int cgroup_migrate(struct task_struct *leader, bool threadgroup,
 
 int cgroup_attach_task(struct cgroup *dst_cgrp, struct task_struct *leader,
 		       bool threadgroup);
+void cgroup_attach_lock(void);
+void cgroup_attach_unlock(void);
 struct task_struct *cgroup_procs_write_start(char *buf, bool threadgroup)
 	__acquires(&cgroup_threadgroup_rwsem);
 void cgroup_procs_write_finish(struct task_struct *task)
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index c4cc6c1ddacde130b839f188fe80d5d620f997c5..8bd36f2143eb92f195ccec16d22c8794cbd9c466 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -55,7 +55,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk)
 	int retval = 0;
 
 	mutex_lock(&cgroup_mutex);
-	percpu_down_write(&cgroup_threadgroup_rwsem);
+	cgroup_attach_lock();
 	for_each_root(root) {
 		struct cgroup *from_cgrp;
 
@@ -70,7 +70,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk)
 		if (retval)
 			break;
 	}
-	percpu_up_write(&cgroup_threadgroup_rwsem);
+	cgroup_attach_unlock();
 	mutex_unlock(&cgroup_mutex);
 
 	return retval;
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 170cc5bc7da2b46682091d1b67ce78f20c1a1aa6..4d01867f7b85b38445dde05ef8150a40b33cb6a0 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -2236,7 +2236,7 @@ EXPORT_SYMBOL_GPL(task_cgroup_path);
  * write-locking cgroup_threadgroup_rwsem. This allows ->attach() to assume that
  * CPU hotplug is disabled on entry.
  */
-static void cgroup_attach_lock(void)
+void cgroup_attach_lock(void)
 {
 	get_online_cpus();
 	percpu_down_write(&cgroup_threadgroup_rwsem);
@@ -2246,7 +2246,7 @@ static void cgroup_attach_lock(void)
  * cgroup_attach_unlock - Undo cgroup_attach_lock()
  * @lock_threadgroup: whether to up_write cgroup_threadgroup_rwsem
  */
-static void cgroup_attach_unlock(void)
+void cgroup_attach_unlock(void)
 {
 	percpu_up_write(&cgroup_threadgroup_rwsem);
 	put_online_cpus();