Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  clockevents: make device shutdown robust
  clocksource, acpi_pm.c: fix check for monotonicity
  clockevents: remove WARN_ON which was used to gather information

5 files changed, 29 insertions, 19 deletions

diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
index 4eee533f3f4a..71d2ac4e3f46 100644
--- a/drivers/clocksource/acpi_pm.c
+++ b/drivers/clocksource/acpi_pm.c
@@ -178,11 +178,13 @@ static int verify_pmtmr_rate(void)
 
 /* Number of monotonicity checks to perform during initialization */
 #define ACPI_PM_MONOTONICITY_CHECKS 10
+/* Number of reads we try to get two different values */
+#define ACPI_PM_READ_CHECKS 10000
 
 static int __init init_acpi_pm_clocksource(void)
 {
         cycle_t value1, value2;
-        unsigned int i, j, good = 0;
+        unsigned int i, j = 0;
 
         if (!pmtmr_ioport)
                 return -ENODEV;
@@ -192,29 +194,26 @@ static int __init init_acpi_pm_clocksource(void)
 
         /* "verify" this timing source: */
         for (j = 0; j < ACPI_PM_MONOTONICITY_CHECKS; j++) {
+                udelay(100 * j);
                 value1 = clocksource_acpi_pm.read();
-                for (i = 0; i < 10000; i++) {
+                for (i = 0; i < ACPI_PM_READ_CHECKS; i++) {
                         value2 = clocksource_acpi_pm.read();
                         if (value2 == value1)
                                 continue;
                         if (value2 > value1)
-                                good++;
                                 break;
                         if ((value2 < value1) && ((value2) < 0xFFF))
-                                good++;
                                 break;
                         printk(KERN_INFO "PM-Timer had inconsistent results:"
                                " 0x%#llx, 0x%#llx - aborting.\n",
                                value1, value2);
                         return -EINVAL;
                 }
-                udelay(300 * i);
-        }
-
-        if (good != ACPI_PM_MONOTONICITY_CHECKS) {
-                printk(KERN_INFO "PM-Timer failed consistency check "
-                       " (0x%#llx) - aborting.\n", value1);
-                return -ENODEV;
+                if (i == ACPI_PM_READ_CHECKS) {
+                        printk(KERN_INFO "PM-Timer failed consistency check "
+                               " (0x%#llx) - aborting.\n", value1);
+                        return -ENODEV;
+                }
         }
 
         if (verify_pmtmr_rate() != 0)
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 1876b526c778..f8d968063cea 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -72,6 +72,16 @@ void clockevents_set_mode(struct clock_event_device *dev,
 }
 
 /**
+ * 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)
  *
@@ -206,7 +216,7 @@ 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);
 }
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 2f5a38294bf9..f1f3eee28113 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -236,8 +236,7 @@ static void tick_do_broadcast_on_off(void *why)
                 if (!cpu_isset(cpu, tick_broadcast_mask)) {
                         cpu_set(cpu, tick_broadcast_mask);
                         if (td->mode == TICKDEV_MODE_PERIODIC)
-                                clockevents_set_mode(dev,
-                                                     CLOCK_EVT_MODE_SHUTDOWN);
+                                clockevents_shutdown(dev);
                 }
                 if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE)
                         tick_broadcast_force = 1;
@@ -254,7 +253,7 @@ static void tick_do_broadcast_on_off(void *why)
 
         if (cpus_empty(tick_broadcast_mask)) {
                 if (!bc_stopped)
-                        clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+                        clockevents_shutdown(bc);
         } else if (bc_stopped) {
                 if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
                         tick_broadcast_start_periodic(bc);
@@ -306,7 +305,7 @@ void tick_shutdown_broadcast(unsigned int *cpup)
 
         if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) {
                 if (bc && cpus_empty(tick_broadcast_mask))
-                        clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+                        clockevents_shutdown(bc);
         }
 
         spin_unlock_irqrestore(&tick_broadcast_lock, flags);
@@ -321,7 +320,7 @@ void tick_suspend_broadcast(void)
 
         bc = tick_broadcast_device.evtdev;
         if (bc)
-                clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+                clockevents_shutdown(bc);
 
         spin_unlock_irqrestore(&tick_broadcast_lock, flags);
 }
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index c4777193d567..019315ebf9de 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -249,7 +249,7 @@ static int tick_check_new_device(struct clock_event_device *newdev)
          * not give it back to the clockevents layer !
          */
         if (tick_is_broadcast_device(curdev)) {
-                clockevents_set_mode(curdev, CLOCK_EVT_MODE_SHUTDOWN);
+                clockevents_shutdown(curdev);
                 curdev = NULL;
         }
         clockevents_exchange_device(curdev, newdev);
@@ -311,7 +311,7 @@ static void tick_suspend(void)
         unsigned long flags;
 
         spin_lock_irqsave(&tick_device_lock, flags);
-        clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_SHUTDOWN);
+        clockevents_shutdown(td->evtdev);
         spin_unlock_irqrestore(&tick_device_lock, flags);
 }
 
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index 0ffc2918ea6f..6e9db9734aa6 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -10,6 +10,8 @@ extern int tick_do_timer_cpu __read_mostly;
 extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
 extern void tick_handle_periodic(struct clock_event_device *dev);
 
+extern void clockevents_shutdown(struct clock_event_device *dev);
+
 /*
  * NO_HZ / high resolution timer shared code
  */