Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6

1 files changed, 14 insertions, 7 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index f28f19e65b5..f06950c8a6c 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -668,6 +668,8 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32;
  */
 unsigned int sysctl_sched_rt_period = 1000000;
 
+static __read_mostly int scheduler_running;
+
 /*
  * part of the period that we allow rt tasks to run in us.
  * default: 0.95s
@@ -689,14 +691,16 @@ unsigned long long cpu_clock(int cpu)
 	unsigned long flags;
 	struct rq *rq;
 
-	local_irq_save(flags);
-	rq = cpu_rq(cpu);
 	/*
 	 * Only call sched_clock() if the scheduler has already been
 	 * initialized (some code might call cpu_clock() very early):
 	 */
-	if (rq->idle)
-		update_rq_clock(rq);
+	if (unlikely(!scheduler_running))
+		return 0;
+
+	local_irq_save(flags);
+	rq = cpu_rq(cpu);
+	update_rq_clock(rq);
 	now = rq->clock;
 	local_irq_restore(flags);
 
@@ -1831,6 +1835,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
 	long old_state;
 	struct rq *rq;
 
+	smp_wmb();
 	rq = task_rq_lock(p, &flags);
 	old_state = p->state;
 	if (!(old_state & state))
@@ -3766,7 +3771,7 @@ void scheduler_tick(void)
 
 #if defined(CONFIG_PREEMPT) && defined(CONFIG_DEBUG_PREEMPT)
 
-void add_preempt_count(int val)
+void __kprobes add_preempt_count(int val)
 {
 	/*
 	 * Underflow?
@@ -3782,7 +3787,7 @@ void add_preempt_count(int val)
 }
 EXPORT_SYMBOL(add_preempt_count);
 
-void sub_preempt_count(int val)
+void __kprobes sub_preempt_count(int val)
 {
 	/*
 	 * Underflow?
@@ -3884,7 +3889,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev)
 asmlinkage void __sched schedule(void)
 {
 	struct task_struct *prev, *next;
-	long *switch_count;
+	unsigned long *switch_count;
 	struct rq *rq;
 	int cpu;
 
@@ -7283,6 +7288,8 @@ void __init sched_init(void)
 	 * During early bootup we pretend to be a normal task:
 	 */
 	current->sched_class = &fair_sched_class;
+
+	scheduler_running = 1;
 }
 
 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP