sched: Use TASK_WAKING for fork wakups

commit 06b83b5f upstream

For later convenience use TASK_WAKING for fresh tasks.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <20091216170517.732561278@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kernel/sched.c

@@ -2538,14 +2538,6 @@ static void __sched_fork(struct task_struct *p)
 #ifdef CONFIG_PREEMPT_NOTIFIERS
 	INIT_HLIST_HEAD(&p->preempt_notifiers);
 #endif
-
-	/*
-	 * We mark the process as running here, but have not actually
-	 * inserted it onto the runqueue yet. This guarantees that
-	 * nobody will actually run it, and a signal or other external
-	 * event cannot wake it up and insert it on the runqueue either.
-	 */
-	p->state = TASK_RUNNING;
 }
 
 /*
@@ -2556,6 +2548,12 @@ void sched_fork(struct task_struct *p, int clone_flags)
 	int cpu = get_cpu();
 
 	__sched_fork(p);
+	/*
+	 * We mark the process as waking here. This guarantees that
+	 * nobody will actually run it, and a signal or other external
+	 * event cannot wake it up and insert it on the runqueue either.
+	 */
+	p->state = TASK_WAKING;
 
 	/*
 	 * Revert to default priority/policy on fork if requested.
@@ -2624,7 +2622,8 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
 	struct rq *rq;
 
 	rq = task_rq_lock(p, &flags);
-	BUG_ON(p->state != TASK_RUNNING);
+	BUG_ON(p->state != TASK_WAKING);
+	p->state = TASK_RUNNING;
 	update_rq_clock(rq);
 	activate_task(rq, p, 0);
 	trace_sched_wakeup_new(rq, p, 1);
@@ -7034,6 +7033,7 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
 	spin_lock_irqsave(&rq->lock, flags);
 
 	__sched_fork(idle);
+	idle->state = TASK_RUNNING;
 	idle->se.exec_start = sched_clock();
 
 	cpumask_copy(&idle->cpus_allowed, cpumask_of(cpu));