kprobes: Move enable/disable_kprobe() out from debugfs code
[safe/jmp/linux-2.6] / kernel / timer.c
index 54d3912..aeb6a54 100644 (file)
@@ -37,8 +37,9 @@
 #include <linux/delay.h>
 #include <linux/tick.h>
 #include <linux/kallsyms.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
 #include <linux/sched.h>
+#include <linux/slab.h>
 
 #include <asm/uaccess.h>
 #include <asm/unistd.h>
@@ -46,6 +47,9 @@
 #include <asm/timex.h>
 #include <asm/io.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/timer.h>
+
 u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
 
 EXPORT_SYMBOL(jiffies_64);
@@ -72,6 +76,7 @@ struct tvec_base {
        spinlock_t lock;
        struct timer_list *running_timer;
        unsigned long timer_jiffies;
+       unsigned long next_timer;
        struct tvec_root tv1;
        struct tvec tv2;
        struct tvec tv3;
@@ -380,6 +385,8 @@ static void timer_stats_account_timer(struct timer_list *timer)
 {
        unsigned int flag = 0;
 
+       if (likely(!timer->start_site))
+               return;
        if (unlikely(tbase_get_deferrable(timer->base)))
                flag |= TIMER_STATS_FLAG_DEFERRABLE;
 
@@ -518,6 +525,25 @@ static inline void debug_timer_activate(struct timer_list *timer) { }
 static inline void debug_timer_deactivate(struct timer_list *timer) { }
 #endif
 
+static inline void debug_init(struct timer_list *timer)
+{
+       debug_timer_init(timer);
+       trace_timer_init(timer);
+}
+
+static inline void
+debug_activate(struct timer_list *timer, unsigned long expires)
+{
+       debug_timer_activate(timer);
+       trace_timer_start(timer, expires);
+}
+
+static inline void debug_deactivate(struct timer_list *timer)
+{
+       debug_timer_deactivate(timer);
+       trace_timer_cancel(timer);
+}
+
 static void __init_timer(struct timer_list *timer,
                         const char *name,
                         struct lock_class_key *key)
@@ -546,7 +572,7 @@ void init_timer_key(struct timer_list *timer,
                    const char *name,
                    struct lock_class_key *key)
 {
-       debug_timer_init(timer);
+       debug_init(timer);
        __init_timer(timer, name, key);
 }
 EXPORT_SYMBOL(init_timer_key);
@@ -565,7 +591,7 @@ static inline void detach_timer(struct timer_list *timer,
 {
        struct list_head *entry = &timer->entry;
 
-       debug_timer_deactivate(timer);
+       debug_deactivate(timer);
 
        __list_del(entry->prev, entry->next);
        if (clear_pending)
@@ -620,15 +646,16 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
 
        if (timer_pending(timer)) {
                detach_timer(timer, 0);
+               if (timer->expires == base->next_timer &&
+                   !tbase_get_deferrable(timer->base))
+                       base->next_timer = base->timer_jiffies;
                ret = 1;
        } else {
                if (pending_only)
                        goto out_unlock;
        }
 
-       debug_timer_activate(timer);
-
-       new_base = __get_cpu_var(tvec_bases);
+       debug_activate(timer, expires);
 
        cpu = smp_processor_id();
 
@@ -661,6 +688,9 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
        }
 
        timer->expires = expires;
+       if (time_before(timer->expires, base->next_timer) &&
+           !tbase_get_deferrable(timer->base))
+               base->next_timer = timer->expires;
        internal_add_timer(base, timer);
 
 out_unlock:
@@ -712,7 +742,7 @@ int mod_timer(struct timer_list *timer, unsigned long expires)
         * networking code - if the timer is re-modified
         * to be the same thing then just return:
         */
-       if (timer->expires == expires && timer_pending(timer))
+       if (timer_pending(timer) && timer->expires == expires)
                return 1;
 
        return __mod_timer(timer, expires, false, TIMER_NOT_PINNED);
@@ -778,7 +808,10 @@ void add_timer_on(struct timer_list *timer, int cpu)
        BUG_ON(timer_pending(timer) || !timer->function);
        spin_lock_irqsave(&base->lock, flags);
        timer_set_base(timer, base);
-       debug_timer_activate(timer);
+       debug_activate(timer, timer->expires);
+       if (time_before(timer->expires, base->next_timer) &&
+           !tbase_get_deferrable(timer->base))
+               base->next_timer = timer->expires;
        internal_add_timer(base, timer);
        /*
         * Check whether the other CPU is idle and needs to be
@@ -815,6 +848,9 @@ int del_timer(struct timer_list *timer)
                base = lock_timer_base(timer, &flags);
                if (timer_pending(timer)) {
                        detach_timer(timer, 1);
+                       if (timer->expires == base->next_timer &&
+                           !tbase_get_deferrable(timer->base))
+                               base->next_timer = base->timer_jiffies;
                        ret = 1;
                }
                spin_unlock_irqrestore(&base->lock, flags);
@@ -845,9 +881,13 @@ int try_to_del_timer_sync(struct timer_list *timer)
        if (base->running_timer == timer)
                goto out;
 
+       timer_stats_timer_clear_start_info(timer);
        ret = 0;
        if (timer_pending(timer)) {
                detach_timer(timer, 1);
+               if (timer->expires == base->next_timer &&
+                   !tbase_get_deferrable(timer->base))
+                       base->next_timer = base->timer_jiffies;
                ret = 1;
        }
 out:
@@ -982,7 +1022,9 @@ static inline void __run_timers(struct tvec_base *base)
                                 */
                                lock_map_acquire(&lockdep_map);
 
+                               trace_timer_expire_entry(timer);
                                fn(data);
+                               trace_timer_expire_exit(timer);
 
                                lock_map_release(&lockdep_map);
 
@@ -1005,8 +1047,8 @@ static inline void __run_timers(struct tvec_base *base)
 #ifdef CONFIG_NO_HZ
 /*
  * Find out when the next timer event is due to happen. This
- * is used on S/390 to stop all activity when a cpus is idle.
- * This functions needs to be called disabled.
+ * is used on S/390 to stop all activity when a CPU is idle.
+ * This function needs to be called with interrupts disabled.
  */
 static unsigned long __next_timer_interrupt(struct tvec_base *base)
 {
@@ -1132,7 +1174,9 @@ unsigned long get_next_timer_interrupt(unsigned long now)
        unsigned long expires;
 
        spin_lock(&base->lock);
-       expires = __next_timer_interrupt(base);
+       if (time_before_eq(base->next_timer, base->timer_jiffies))
+               base->next_timer = __next_timer_interrupt(base);
+       expires = base->next_timer;
        spin_unlock(&base->lock);
 
        if (time_before_eq(expires, now))
@@ -1154,9 +1198,9 @@ void update_process_times(int user_tick)
        /* Note: this timer irq context must be accounted for as well. */
        account_process_tick(p, user_tick);
        run_local_timers();
-       if (rcu_pending(cpu))
-               rcu_check_callbacks(cpu, user_tick);
+       rcu_check_callbacks(cpu, user_tick);
        printk_tick();
+       perf_event_do_pending();
        scheduler_tick();
        run_posix_cpu_timers(p);
 }
@@ -1168,8 +1212,6 @@ static void run_timer_softirq(struct softirq_action *h)
 {
        struct tvec_base *base = __get_cpu_var(tvec_bases);
 
-       perf_counter_do_pending();
-
        hrtimer_run_pending();
 
        if (time_after_eq(jiffies, base->timer_jiffies))
@@ -1521,6 +1563,7 @@ static int __cpuinit init_timers_cpu(int cpu)
                INIT_LIST_HEAD(base->tv1.vec + j);
 
        base->timer_jiffies = jiffies;
+       base->next_timer = base->timer_jiffies;
        return 0;
 }
 
@@ -1533,6 +1576,9 @@ static void migrate_timer_list(struct tvec_base *new_base, struct list_head *hea
                timer = list_first_entry(head, struct timer_list, entry);
                detach_timer(timer, 0);
                timer_set_base(timer, new_base);
+               if (time_before(timer->expires, new_base->next_timer) &&
+                   !tbase_get_deferrable(timer->base))
+                       new_base->next_timer = timer->expires;
                internal_add_timer(new_base, timer);
        }
 }