Correct nr_processes() when CPUs have been unplugged
[safe/jmp/linux-2.6] / kernel / hrtimer.c
index e2f91ec..3e1c36e 100644 (file)
@@ -48,6 +48,8 @@
 
 #include <asm/uaccess.h>
 
+#include <trace/events/timer.h>
+
 /*
  * The timer bases:
  *
@@ -429,6 +431,7 @@ void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
        debug_object_init_on_stack(timer, &hrtimer_debug_descr);
        __hrtimer_init(timer, clock_id, mode);
 }
+EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
 
 void destroy_hrtimer_on_stack(struct hrtimer *timer)
 {
@@ -441,6 +444,26 @@ static inline void debug_hrtimer_activate(struct hrtimer *timer) { }
 static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }
 #endif
 
+static inline void
+debug_init(struct hrtimer *timer, clockid_t clockid,
+          enum hrtimer_mode mode)
+{
+       debug_hrtimer_init(timer);
+       trace_hrtimer_init(timer, clockid, mode);
+}
+
+static inline void debug_activate(struct hrtimer *timer)
+{
+       debug_hrtimer_activate(timer);
+       trace_hrtimer_start(timer);
+}
+
+static inline void debug_deactivate(struct hrtimer *timer)
+{
+       debug_hrtimer_deactivate(timer);
+       trace_hrtimer_cancel(timer);
+}
+
 /* High resolution timer related functions */
 #ifdef CONFIG_HIGH_RES_TIMERS
 
@@ -486,13 +509,14 @@ static inline int hrtimer_hres_active(void)
  * next event
  * Called with interrupts disabled and base->lock held
  */
-static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
+static void
+hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
 {
        int i;
        struct hrtimer_clock_base *base = cpu_base->clock_base;
-       ktime_t expires;
+       ktime_t expires, expires_next;
 
-       cpu_base->expires_next.tv64 = KTIME_MAX;
+       expires_next.tv64 = KTIME_MAX;
 
        for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
                struct hrtimer *timer;
@@ -508,10 +532,15 @@ static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
                 */
                if (expires.tv64 < 0)
                        expires.tv64 = 0;
-               if (expires.tv64 < cpu_base->expires_next.tv64)
-                       cpu_base->expires_next = expires;
+               if (expires.tv64 < expires_next.tv64)
+                       expires_next = expires;
        }
 
+       if (skip_equal && expires_next.tv64 == cpu_base->expires_next.tv64)
+               return;
+
+       cpu_base->expires_next.tv64 = expires_next.tv64;
+
        if (cpu_base->expires_next.tv64 != KTIME_MAX)
                tick_program_event(cpu_base->expires_next, 1);
 }
@@ -594,7 +623,7 @@ static void retrigger_next_event(void *arg)
        base->clock_base[CLOCK_REALTIME].offset =
                timespec_to_ktime(realtime_offset);
 
-       hrtimer_force_reprogram(base);
+       hrtimer_force_reprogram(base, 0);
        spin_unlock(&base->lock);
 }
 
@@ -697,8 +726,6 @@ static int hrtimer_switch_to_hres(void)
        /* "Retrigger" the interrupt to get things going */
        retrigger_next_event(NULL);
        local_irq_restore(flags);
-       printk(KERN_DEBUG "Switched to high resolution mode on CPU %d\n",
-              smp_processor_id());
        return 1;
 }
 
@@ -707,7 +734,8 @@ static int hrtimer_switch_to_hres(void)
 static inline int hrtimer_hres_active(void) { return 0; }
 static inline int hrtimer_is_hres_enabled(void) { return 0; }
 static inline int hrtimer_switch_to_hres(void) { return 0; }
-static inline void hrtimer_force_reprogram(struct hrtimer_cpu_base *base) { }
+static inline void
+hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
 static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
                                            struct hrtimer_clock_base *base,
                                            int wakeup)
@@ -797,7 +825,7 @@ static int enqueue_hrtimer(struct hrtimer *timer,
        struct hrtimer *entry;
        int leftmost = 1;
 
-       debug_hrtimer_activate(timer);
+       debug_activate(timer);
 
        /*
         * Find the right place in the rbtree:
@@ -850,19 +878,29 @@ static void __remove_hrtimer(struct hrtimer *timer,
                             struct hrtimer_clock_base *base,
                             unsigned long newstate, int reprogram)
 {
-       if (timer->state & HRTIMER_STATE_ENQUEUED) {
-               /*
-                * Remove the timer from the rbtree and replace the
-                * first entry pointer if necessary.
-                */
-               if (base->first == &timer->node) {
-                       base->first = rb_next(&timer->node);
-                       /* Reprogram the clock event device. if enabled */
-                       if (reprogram && hrtimer_hres_active())
-                               hrtimer_force_reprogram(base->cpu_base);
+       if (!(timer->state & HRTIMER_STATE_ENQUEUED))
+               goto out;
+
+       /*
+        * Remove the timer from the rbtree and replace the first
+        * entry pointer if necessary.
+        */
+       if (base->first == &timer->node) {
+               base->first = rb_next(&timer->node);
+#ifdef CONFIG_HIGH_RES_TIMERS
+               /* Reprogram the clock event device. if enabled */
+               if (reprogram && hrtimer_hres_active()) {
+                       ktime_t expires;
+
+                       expires = ktime_sub(hrtimer_get_expires(timer),
+                                           base->offset);
+                       if (base->cpu_base->expires_next.tv64 == expires.tv64)
+                               hrtimer_force_reprogram(base->cpu_base, 1);
                }
-               rb_erase(&timer->node, &base->active);
+#endif
        }
+       rb_erase(&timer->node, &base->active);
+out:
        timer->state = newstate;
 }
 
@@ -883,7 +921,7 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
                 * reprogramming happens in the interrupt handler. This is a
                 * rare case and less expensive than a smp call.
                 */
-               debug_hrtimer_deactivate(timer);
+               debug_deactivate(timer);
                timer_stats_hrtimer_clear_start_info(timer);
                reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases);
                __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE,
@@ -1116,7 +1154,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
                  enum hrtimer_mode mode)
 {
-       debug_hrtimer_init(timer);
+       debug_init(timer, clock_id, mode);
        __hrtimer_init(timer, clock_id, mode);
 }
 EXPORT_SYMBOL_GPL(hrtimer_init);
@@ -1140,7 +1178,7 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp)
 }
 EXPORT_SYMBOL_GPL(hrtimer_get_res);
 
-static void __run_hrtimer(struct hrtimer *timer)
+static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
 {
        struct hrtimer_clock_base *base = timer->base;
        struct hrtimer_cpu_base *cpu_base = base->cpu_base;
@@ -1149,7 +1187,7 @@ static void __run_hrtimer(struct hrtimer *timer)
 
        WARN_ON(!irqs_disabled());
 
-       debug_hrtimer_deactivate(timer);
+       debug_deactivate(timer);
        __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0);
        timer_stats_account_hrtimer(timer);
        fn = timer->function;
@@ -1160,7 +1198,9 @@ static void __run_hrtimer(struct hrtimer *timer)
         * the timer base.
         */
        spin_unlock(&cpu_base->lock);
+       trace_hrtimer_expire_entry(timer, now);
        restart = fn(timer);
+       trace_hrtimer_expire_exit(timer);
        spin_lock(&cpu_base->lock);
 
        /*
@@ -1271,7 +1311,7 @@ void hrtimer_interrupt(struct clock_event_device *dev)
                                break;
                        }
 
-                       __run_hrtimer(timer);
+                       __run_hrtimer(timer, &basenow);
                }
                base++;
        }
@@ -1393,7 +1433,7 @@ void hrtimer_run_queues(void)
                                        hrtimer_get_expires_tv64(timer))
                                break;
 
-                       __run_hrtimer(timer);
+                       __run_hrtimer(timer, &base->softirq_time);
                }
                spin_unlock(&cpu_base->lock);
        }
@@ -1420,6 +1460,7 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
        sl->timer.function = hrtimer_wakeup;
        sl->task = task;
 }
+EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
 
 static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
 {
@@ -1569,7 +1610,7 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
        while ((node = rb_first(&old_base->active))) {
                timer = rb_entry(node, struct hrtimer, node);
                BUG_ON(hrtimer_callback_running(timer));
-               debug_hrtimer_deactivate(timer);
+               debug_deactivate(timer);
 
                /*
                 * Mark it as STATE_MIGRATE not INACTIVE otherwise the