sched: Fix select_task_rq() vs hotplug issues

[safe/jmp/linux-2.6] / kernel / time / clockevents.c

diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 3d1e3e1..3d5fc0f 100644 (file)
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -18,6 +18,9 @@
 #include <linux/notifier.h>
 #include <linux/smp.h>
 #include <linux/sysdev.h>
+#include <linux/tick.h>
+
+#include "tick-internal.h"
 
 /* The registered clock event devices */
 static LIST_HEAD(clockevent_devices);
@@ -27,7 +30,7 @@ static LIST_HEAD(clockevents_released);
 static RAW_NOTIFIER_HEAD(clockevents_chain);
 
 /* Protection for the above */
-static DEFINE_SPINLOCK(clockevents_lock);
+static DEFINE_RAW_SPINLOCK(clockevents_lock);
 
 /**
  * clockevents_delta2ns - Convert a latch value (device ticks) to nanoseconds
@@ -36,10 +39,9 @@ static DEFINE_SPINLOCK(clockevents_lock);
  *
  * Math helper, returns latch value converted to nanoseconds (bound checked)
  */
-unsigned long clockevent_delta2ns(unsigned long latch,
-                                 struct clock_event_device *evt)
+u64 clockevent_delta2ns(unsigned long latch, struct clock_event_device *evt)
 {
-       u64 clc = ((u64) latch << evt->shift);
+       u64 clc = (u64) latch << evt->shift;
 
        if (unlikely(!evt->mult)) {
                evt->mult = 1;
@@ -49,11 +51,12 @@ unsigned long clockevent_delta2ns(unsigned long latch,
        do_div(clc, evt->mult);
        if (clc < 1000)
                clc = 1000;
-       if (clc > LONG_MAX)
-               clc = LONG_MAX;
+       if (clc > KTIME_MAX)
+               clc = KTIME_MAX;
 
-       return (unsigned long) clc;
+       return clc;
 }
+EXPORT_SYMBOL_GPL(clockevent_delta2ns);
 
 /**
  * clockevents_set_mode - set the operating mode of a clock event device
@@ -68,10 +71,31 @@ void clockevents_set_mode(struct clock_event_device *dev,
        if (dev->mode != mode) {
                dev->set_mode(mode, dev);
                dev->mode = mode;
+
+               /*
+                * A nsec2cyc multiplicator of 0 is invalid and we'd crash
+                * on it, so fix it up and emit a warning:
+                */
+               if (mode == CLOCK_EVT_MODE_ONESHOT) {
+                       if (unlikely(!dev->mult)) {
+                               dev->mult = 1;
+                               WARN_ON(1);
+                       }
+               }
        }
 }
 
 /**
+ * clockevents_shutdown - shutdown the device and clear next_event
+ * @dev:       device to shutdown
+ */
+void clockevents_shutdown(struct clock_event_device *dev)
+{
+       clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
+       dev->next_event.tv64 = KTIME_MAX;
+}
+
+/**
  * clockevents_program_event - Reprogram the clock event device.
  * @expires:   absolute expiry time (monotonic clock)
  *
@@ -114,11 +138,12 @@ int clockevents_program_event(struct clock_event_device *dev, ktime_t expires,
  */
 int clockevents_register_notifier(struct notifier_block *nb)
 {
+       unsigned long flags;
        int ret;
 
-       spin_lock(&clockevents_lock);
+       raw_spin_lock_irqsave(&clockevents_lock, flags);
        ret = raw_notifier_chain_register(&clockevents_chain, nb);
-       spin_unlock(&clockevents_lock);
+       raw_spin_unlock_irqrestore(&clockevents_lock, flags);
 
        return ret;
 }
@@ -155,29 +180,25 @@ static void clockevents_notify_released(void)
  */
 void clockevents_register_device(struct clock_event_device *dev)
 {
+       unsigned long flags;
+
        BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED);
-       /*
-        * A nsec2cyc multiplicator of 0 is invalid and we'd crash
-        * on it, so fix it up and emit a warning:
-        */
-       if (unlikely(!dev->mult)) {
-               dev->mult = 1;
-               WARN_ON(1);
-       }
+       BUG_ON(!dev->cpumask);
 
-       spin_lock(&clockevents_lock);
+       raw_spin_lock_irqsave(&clockevents_lock, flags);
 
        list_add(&dev->list, &clockevent_devices);
        clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev);
        clockevents_notify_released();
 
-       spin_unlock(&clockevents_lock);
+       raw_spin_unlock_irqrestore(&clockevents_lock, flags);
 }
+EXPORT_SYMBOL_GPL(clockevents_register_device);
 
 /*
  * Noop handler when we shut down an event device
  */
-static void clockevents_handle_noop(struct clock_event_device *dev)
+void clockevents_handle_noop(struct clock_event_device *dev)
 {
 }
 
@@ -199,7 +220,6 @@ void clockevents_exchange_device(struct clock_event_device *old,
         * released list and do a notify add later.
         */
        if (old) {
-               old->event_handler = clockevents_handle_noop;
                clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED);
                list_del(&old->list);
                list_add(&old->list, &clockevents_released);
@@ -207,7 +227,7 @@ void clockevents_exchange_device(struct clock_event_device *old,
 
        if (new) {
                BUG_ON(new->mode != CLOCK_EVT_MODE_UNUSED);
-               clockevents_set_mode(new, CLOCK_EVT_MODE_SHUTDOWN);
+               clockevents_shutdown(new);
        }
        local_irq_restore(flags);
 }
@@ -219,8 +239,9 @@ void clockevents_exchange_device(struct clock_event_device *old,
 void clockevents_notify(unsigned long reason, void *arg)
 {
        struct list_head *node, *tmp;
+       unsigned long flags;
 
-       spin_lock(&clockevents_lock);
+       raw_spin_lock_irqsave(&clockevents_lock, flags);
        clockevents_do_notify(reason, arg);
 
        switch (reason) {
@@ -235,7 +256,7 @@ void clockevents_notify(unsigned long reason, void *arg)
        default:
                break;
        }
-       spin_unlock(&clockevents_lock);
+       raw_spin_unlock_irqrestore(&clockevents_lock, flags);
 }
 EXPORT_SYMBOL_GPL(clockevents_notify);
 #endif