Merge tag 'for-linus-20150724' of git://git.infradead.org/linux-mtd

[karo-tx-linux.git] / kernel / sched / core.c

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index b803e1b8ab0cf7eb381600a32855b822be3c8c89..78b4bad10081c6b23894ac1d5d7b6900ab32362a 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2164,7 +2164,7 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p)
        set_task_cpu(p, cpu);
        raw_spin_unlock_irqrestore(&p->pi_lock, flags);
 
-#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+#ifdef CONFIG_SCHED_INFO
        if (likely(sched_info_on()))
                memset(&p->sched_info, 0, sizeof(p->sched_info));
 #endif
@@ -2320,13 +2320,27 @@ void wake_up_new_task(struct task_struct *p)
 
 static struct static_key preempt_notifier_key = STATIC_KEY_INIT_FALSE;
 
+void preempt_notifier_inc(void)
+{
+       static_key_slow_inc(&preempt_notifier_key);
+}
+EXPORT_SYMBOL_GPL(preempt_notifier_inc);
+
+void preempt_notifier_dec(void)
+{
+       static_key_slow_dec(&preempt_notifier_key);
+}
+EXPORT_SYMBOL_GPL(preempt_notifier_dec);
+
 /**
  * preempt_notifier_register - tell me when current is being preempted & rescheduled
  * @notifier: notifier struct to register
  */
 void preempt_notifier_register(struct preempt_notifier *notifier)
 {
-       static_key_slow_inc(&preempt_notifier_key);
+       if (!static_key_false(&preempt_notifier_key))
+               WARN(1, "registering preempt_notifier while notifiers disabled\n");
+
        hlist_add_head(&notifier->link, &current->preempt_notifiers);
 }
 EXPORT_SYMBOL_GPL(preempt_notifier_register);
@@ -2340,7 +2354,6 @@ EXPORT_SYMBOL_GPL(preempt_notifier_register);
 void preempt_notifier_unregister(struct preempt_notifier *notifier)
 {
        hlist_del(&notifier->link);
-       static_key_slow_dec(&preempt_notifier_key);
 }
 EXPORT_SYMBOL_GPL(preempt_notifier_unregister);