Merge branch 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[sfrench/cifs-2.6.git] / kernel / timer.c

diff --git a/kernel/timer.c b/kernel/timer.c
index 9b77fc9a9ac8286074b1784771dac7c0eb2a08e2..b4555568b4e4ad16f34a887eabed6f21e05abfba 100644 (file)
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -491,14 +491,18 @@ static inline void debug_timer_free(struct timer_list *timer)
        debug_object_free(timer, &timer_debug_descr);
 }
 
-static void __init_timer(struct timer_list *timer);
+static void __init_timer(struct timer_list *timer,
+                        const char *name,
+                        struct lock_class_key *key);
 
-void init_timer_on_stack(struct timer_list *timer)
+void init_timer_on_stack_key(struct timer_list *timer,
+                            const char *name,
+                            struct lock_class_key *key)
 {
        debug_object_init_on_stack(timer, &timer_debug_descr);
-       __init_timer(timer);
+       __init_timer(timer, name, key);
 }
-EXPORT_SYMBOL_GPL(init_timer_on_stack);
+EXPORT_SYMBOL_GPL(init_timer_on_stack_key);
 
 void destroy_timer_on_stack(struct timer_list *timer)
 {
@@ -512,7 +516,9 @@ static inline void debug_timer_activate(struct timer_list *timer) { }
 static inline void debug_timer_deactivate(struct timer_list *timer) { }
 #endif
 
-static void __init_timer(struct timer_list *timer)
+static void __init_timer(struct timer_list *timer,
+                        const char *name,
+                        struct lock_class_key *key)
 {
        timer->entry.next = NULL;
        timer->base = __raw_get_cpu_var(tvec_bases);
@@ -521,6 +527,7 @@ static void __init_timer(struct timer_list *timer)
        timer->start_pid = -1;
        memset(timer->start_comm, 0, TASK_COMM_LEN);
 #endif
+       lockdep_init_map(&timer->lockdep_map, name, key, 0);
 }
 
 /**
@@ -530,19 +537,23 @@ static void __init_timer(struct timer_list *timer)
  * init_timer() must be done to a timer prior calling *any* of the
  * other timer functions.
  */
-void init_timer(struct timer_list *timer)
+void init_timer_key(struct timer_list *timer,
+                   const char *name,
+                   struct lock_class_key *key)
 {
        debug_timer_init(timer);
-       __init_timer(timer);
+       __init_timer(timer, name, key);
 }
-EXPORT_SYMBOL(init_timer);
+EXPORT_SYMBOL(init_timer_key);
 
-void init_timer_deferrable(struct timer_list *timer)
+void init_timer_deferrable_key(struct timer_list *timer,
+                              const char *name,
+                              struct lock_class_key *key)
 {
-       init_timer(timer);
+       init_timer_key(timer, name, key);
        timer_set_deferrable(timer);
 }
-EXPORT_SYMBOL(init_timer_deferrable);
+EXPORT_SYMBOL(init_timer_deferrable_key);
 
 static inline void detach_timer(struct timer_list *timer,
                                int clear_pending)
@@ -826,6 +837,15 @@ EXPORT_SYMBOL(try_to_del_timer_sync);
  */
 int del_timer_sync(struct timer_list *timer)
 {
+#ifdef CONFIG_LOCKDEP
+       unsigned long flags;
+
+       local_irq_save(flags);
+       lock_map_acquire(&timer->lockdep_map);
+       lock_map_release(&timer->lockdep_map);
+       local_irq_restore(flags);
+#endif
+
        for (;;) {
                int ret = try_to_del_timer_sync(timer);
                if (ret >= 0)
@@ -897,10 +917,36 @@ static inline void __run_timers(struct tvec_base *base)
 
                        set_running_timer(base, timer);
                        detach_timer(timer, 1);
+
                        spin_unlock_irq(&base->lock);
                        {
                                int preempt_count = preempt_count();
+
+#ifdef CONFIG_LOCKDEP
+                               /*
+                                * It is permissible to free the timer from
+                                * inside the function that is called from
+                                * it, this we need to take into account for
+                                * lockdep too. To avoid bogus "held lock
+                                * freed" warnings as well as problems when
+                                * looking into timer->lockdep_map, make a
+                                * copy and use that here.
+                                */
+                               struct lockdep_map lockdep_map =
+                                       timer->lockdep_map;
+#endif
+                               /*
+                                * Couple the lock chain with the lock chain at
+                                * del_timer_sync() by acquiring the lock_map
+                                * around the fn() call here and in
+                                * del_timer_sync().
+                                */
+                               lock_map_acquire(&lockdep_map);
+
                                fn(data);
+
+                               lock_map_release(&lockdep_map);
+
                                if (preempt_count != preempt_count()) {
                                        printk(KERN_ERR "huh, entered %p "
                                               "with preempt_count %08x, exited"