sched: Use lockdep-based checking on rcu_dereference()

[safe/jmp/linux-2.6] / include / linux / cgroup.h

diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 0008dee..c9bbcb2 100644 (file)
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -28,6 +28,7 @@ struct css_id;
 extern int cgroup_init_early(void);
 extern int cgroup_init(void);
 extern void cgroup_lock(void);
+extern int cgroup_lock_is_held(void);
 extern bool cgroup_lock_live_group(struct cgroup *cgrp);
 extern void cgroup_unlock(void);
 extern void cgroup_fork(struct task_struct *p);
@@ -486,7 +487,9 @@ static inline struct cgroup_subsys_state *cgroup_subsys_state(
 static inline struct cgroup_subsys_state *task_subsys_state(
        struct task_struct *task, int subsys_id)
 {
-       return rcu_dereference(task->cgroups->subsys[subsys_id]);
+       return rcu_dereference_check(task->cgroups->subsys[subsys_id],
+                                    rcu_read_lock_held() ||
+                                    cgroup_lock_is_held());
 }
 
 static inline struct cgroup* task_cgroup(struct task_struct *task,