---

yaml
---
r: 73839
b: refs/heads/master
c: ce96b5a
h: refs/heads/master
i:
  73837: e45fbb6
  73835: 704330b
  73831: 0edfe76
  73823: b82b04c
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: dae51f56204d33444f61d9e7af3ee70aef55daa4
+refs/heads/master: ce96b5ac742801718ae86d2adf0500c5abef3782

trunk/kernel/sched.c

@@ -216,15 +216,15 @@ static inline struct task_group *task_group(struct task_struct *p)
 }
 
 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
-static inline void set_task_cfs_rq(struct task_struct *p)
+static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu)
 {
-	p->se.cfs_rq = task_group(p)->cfs_rq[task_cpu(p)];
-	p->se.parent = task_group(p)->se[task_cpu(p)];
+	p->se.cfs_rq = task_group(p)->cfs_rq[cpu];
+	p->se.parent = task_group(p)->se[cpu];
 }
 
 #else
 
-static inline void set_task_cfs_rq(struct task_struct *p) { }
+static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { }
 
 #endif	/* CONFIG_FAIR_GROUP_SCHED */
 
@@ -1022,10 +1022,16 @@ unsigned long weighted_cpuload(const int cpu)
 
 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
 {
+	set_task_cfs_rq(p, cpu);
 #ifdef CONFIG_SMP
+	/*
+	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
+	 * successfuly executed on another CPU. We must ensure that updates of
+	 * per-task data have been completed by this moment.
+	 */
+	smp_wmb();
 	task_thread_info(p)->cpu = cpu;
 #endif
-	set_task_cfs_rq(p);
 }
 
 #ifdef CONFIG_SMP
@@ -7088,7 +7094,7 @@ void sched_move_task(struct task_struct *tsk)
 	rq = task_rq_lock(tsk, &flags);
 
 	if (tsk->sched_class != &fair_sched_class) {
-		set_task_cfs_rq(tsk);
+		set_task_cfs_rq(tsk, task_cpu(tsk));
 		goto done;
 	}
 
@@ -7103,7 +7109,7 @@ void sched_move_task(struct task_struct *tsk)
 			tsk->sched_class->put_prev_task(rq, tsk);
 	}
 
-	set_task_cfs_rq(tsk);
+	set_task_cfs_rq(tsk, task_cpu(tsk));
 
 	if (on_rq) {
 		if (unlikely(running))