Merge branch 'stacking-fixes' (vfs stacking fixes from Jann)

[cascardo/linux.git] / kernel / sched / core.c

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 7f2cae4..017d539 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2253,9 +2253,11 @@ int sysctl_numa_balancing(struct ctl_table *table, int write,
 #endif
 #endif
 
+#ifdef CONFIG_SCHEDSTATS
+
 DEFINE_STATIC_KEY_FALSE(sched_schedstats);
+static bool __initdata __sched_schedstats = false;
 
-#ifdef CONFIG_SCHEDSTATS
 static void set_schedstats(bool enabled)
 {
        if (enabled)
@@ -2278,11 +2280,16 @@ static int __init setup_schedstats(char *str)
        if (!str)
                goto out;
 
+       /*
+        * This code is called before jump labels have been set up, so we can't
+        * change the static branch directly just yet.  Instead set a temporary
+        * variable so init_schedstats() can do it later.
+        */
        if (!strcmp(str, "enable")) {
-               set_schedstats(true);
+               __sched_schedstats = true;
                ret = 1;
        } else if (!strcmp(str, "disable")) {
-               set_schedstats(false);
+               __sched_schedstats = false;
                ret = 1;
        }
 out:
@@ -2293,6 +2300,11 @@ out:
 }
 __setup("schedstats=", setup_schedstats);
 
+static void __init init_schedstats(void)
+{
+       set_schedstats(__sched_schedstats);
+}
+
 #ifdef CONFIG_PROC_SYSCTL
 int sysctl_schedstats(struct ctl_table *table, int write,
                         void __user *buffer, size_t *lenp, loff_t *ppos)
@@ -2313,8 +2325,10 @@ int sysctl_schedstats(struct ctl_table *table, int write,
                set_schedstats(state);
        return err;
 }
-#endif
-#endif
+#endif /* CONFIG_PROC_SYSCTL */
+#else  /* !CONFIG_SCHEDSTATS */
+static inline void init_schedstats(void) {}
+#endif /* CONFIG_SCHEDSTATS */
 
 /*
  * fork()/clone()-time setup:
@@ -3156,7 +3170,8 @@ static noinline void __schedule_bug(struct task_struct *prev)
 static inline void schedule_debug(struct task_struct *prev)
 {
 #ifdef CONFIG_SCHED_STACK_END_CHECK
-       BUG_ON(task_stack_end_corrupted(prev));
+       if (task_stack_end_corrupted(prev))
+               panic("corrupted stack end detected inside scheduler\n");
 #endif
 
        if (unlikely(in_atomic_preempt_off())) {
@@ -7487,6 +7502,8 @@ void __init sched_init(void)
 #endif
        init_sched_fair_class();
 
+       init_schedstats();
+
        scheduler_running = 1;
 }