diff options
Diffstat (limited to 'kernel/time/clockevents.c')
| -rw-r--r-- | kernel/time/clockevents.c | 80 |
1 files changed, 40 insertions, 40 deletions
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index f5490222e134..f3e831f62906 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -76,7 +76,7 @@ static u64 cev_delta2ns(unsigned long latch, struct clock_event_device *evt, } /** - * clockevents_delta2ns - Convert a latch value (device ticks) to nanoseconds + * clockevent_delta2ns - Convert a latch value (device ticks) to nanoseconds * @latch: value to convert * @evt: pointer to clock event device descriptor * @@ -190,7 +190,7 @@ int clockevents_tick_resume(struct clock_event_device *dev) #ifdef CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST -/* Limit min_delta to a jiffie */ +/* Limit min_delta to a jiffy */ #define MIN_DELTA_LIMIT (NSEC_PER_SEC / HZ) /** @@ -337,18 +337,25 @@ int clockevents_program_event(struct clock_event_device *dev, ktime_t expires, } /* - * Called after a notify add to make devices available which were - * released from the notifier call. + * Called after a clockevent has been added which might + * have replaced a current regular or broadcast device. A + * released normal device might be a suitable replacement + * for the current broadcast device. Similarly a released + * broadcast device might be a suitable replacement for a + * normal device. */ static void clockevents_notify_released(void) { struct clock_event_device *dev; + /* + * Keep iterating as long as tick_check_new_device() + * replaces a device. + */ while (!list_empty(&clockevents_released)) { dev = list_entry(clockevents_released.next, struct clock_event_device, list); - list_del(&dev->list); - list_add(&dev->list, &clockevent_devices); + list_move(&dev->list, &clockevent_devices); tick_check_new_device(dev); } } @@ -576,8 +583,7 @@ void clockevents_exchange_device(struct clock_event_device *old, if (old) { module_put(old->owner); clockevents_switch_state(old, CLOCK_EVT_STATE_DETACHED); - list_del(&old->list); - list_add(&old->list, &clockevents_released); + list_move(&old->list, &clockevents_released); } if (new) { @@ -612,38 +618,30 @@ void clockevents_resume(void) #ifdef CONFIG_HOTPLUG_CPU -# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST /** - * tick_offline_cpu - Take CPU out of the broadcast mechanism + * tick_offline_cpu - Shutdown all clock events related + * to this CPU and take it out of the + * broadcast mechanism. * @cpu: The outgoing CPU * - * Called on the outgoing CPU after it took itself offline. + * Called by the dying CPU during teardown. */ void tick_offline_cpu(unsigned int cpu) { - raw_spin_lock(&clockevents_lock); - tick_broadcast_offline(cpu); - raw_spin_unlock(&clockevents_lock); -} -# endif - -/** - * tick_cleanup_dead_cpu - Cleanup the tick and clockevents of a dead cpu - */ -void tick_cleanup_dead_cpu(int cpu) -{ struct clock_event_device *dev, *tmp; - unsigned long flags; - raw_spin_lock_irqsave(&clockevents_lock, flags); + raw_spin_lock(&clockevents_lock); + tick_broadcast_offline(cpu); tick_shutdown(cpu); + /* * Unregister the clock event devices which were - * released from the users in the notify chain. + * released above. */ list_for_each_entry_safe(dev, tmp, &clockevents_released, list) list_del(&dev->list); + /* * Now check whether the CPU has left unused per cpu devices */ @@ -655,12 +653,13 @@ void tick_cleanup_dead_cpu(int cpu) list_del(&dev->list); } } - raw_spin_unlock_irqrestore(&clockevents_lock, flags); + + raw_spin_unlock(&clockevents_lock); } #endif #ifdef CONFIG_SYSFS -static struct bus_type clockevents_subsys = { +static const struct bus_type clockevents_subsys = { .name = "clockevents", .dev_name = "clockevent", }; @@ -668,9 +667,9 @@ static struct bus_type clockevents_subsys = { static DEFINE_PER_CPU(struct device, tick_percpu_dev); static struct tick_device *tick_get_tick_dev(struct device *dev); -static ssize_t sysfs_show_current_tick_dev(struct device *dev, - struct device_attribute *attr, - char *buf) +static ssize_t current_device_show(struct device *dev, + struct device_attribute *attr, + char *buf) { struct tick_device *td; ssize_t count = 0; @@ -678,20 +677,20 @@ static ssize_t sysfs_show_current_tick_dev(struct device *dev, raw_spin_lock_irq(&clockevents_lock); td = tick_get_tick_dev(dev); if (td && td->evtdev) - count = snprintf(buf, PAGE_SIZE, "%s\n", td->evtdev->name); + count = sysfs_emit(buf, "%s\n", td->evtdev->name); raw_spin_unlock_irq(&clockevents_lock); return count; } -static DEVICE_ATTR(current_device, 0444, sysfs_show_current_tick_dev, NULL); +static DEVICE_ATTR_RO(current_device); /* We don't support the abomination of removable broadcast devices */ -static ssize_t sysfs_unbind_tick_dev(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t count) +static ssize_t unbind_device_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) { char name[CS_NAME_LEN]; ssize_t ret = sysfs_get_uname(buf, name, count); - struct clock_event_device *ce; + struct clock_event_device *ce = NULL, *iter; if (ret < 0) return ret; @@ -699,9 +698,10 @@ static ssize_t sysfs_unbind_tick_dev(struct device *dev, ret = -ENODEV; mutex_lock(&clockevents_mutex); raw_spin_lock_irq(&clockevents_lock); - list_for_each_entry(ce, &clockevent_devices, list) { - if (!strcmp(ce->name, name)) { - ret = __clockevents_try_unbind(ce, dev->id); + list_for_each_entry(iter, &clockevent_devices, list) { + if (!strcmp(iter->name, name)) { + ret = __clockevents_try_unbind(iter, dev->id); + ce = iter; break; } } @@ -714,7 +714,7 @@ static ssize_t sysfs_unbind_tick_dev(struct device *dev, mutex_unlock(&clockevents_mutex); return ret ? ret : count; } -static DEVICE_ATTR(unbind_device, 0200, NULL, sysfs_unbind_tick_dev); +static DEVICE_ATTR_WO(unbind_device); #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST static struct device tick_bc_dev = { |