fix 2.6.32.23 suspend regression caused by commit 6f6198a7

[Not upstream in the same way, as it was fixed differently there]

6f6198a7 sched: kill migration thread in CPU_POST_DEAD instead of CPU_DEAD
leaves migration threads lying about.  Mask out CPU_TASKS_FROZEN.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kernel/sched.c

@@ -7752,10 +7752,9 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 	unsigned long flags;
 	struct rq *rq;
 
-	switch (action) {
+	switch (action & ~CPU_TASKS_FROZEN) {
 
 	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
 		p = kthread_create(migration_thread, hcpu, "migration/%d", cpu);
 		if (IS_ERR(p))
 			return NOTIFY_BAD;
@@ -7770,7 +7769,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 		break;
 
 	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
 		/* Strictly unnecessary, as first user will wake it. */
 		wake_up_process(cpu_rq(cpu)->migration_thread);
 
@@ -7787,7 +7785,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 
 #ifdef CONFIG_HOTPLUG_CPU
 	case CPU_UP_CANCELED:
-	case CPU_UP_CANCELED_FROZEN:
 		if (!cpu_rq(cpu)->migration_thread)
 			break;
 		/* Unbind it from offline cpu so it can run. Fall thru. */
@@ -7812,7 +7809,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 		break;
 
 	case CPU_DEAD:
-	case CPU_DEAD_FROZEN:
 		migrate_live_tasks(cpu);
 		rq = cpu_rq(cpu);
 		/* Idle task back to normal (off runqueue, low prio) */
@@ -7846,7 +7842,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 		break;
 
 	case CPU_DYING:
-	case CPU_DYING_FROZEN:
 		/* Update our root-domain */
 		rq = cpu_rq(cpu);
 		spin_lock_irqsave(&rq->lock, flags);