static char override_name[32];
static int finished_booting;
-/* clocksource_done_booting - Called near the end of bootup
+/* clocksource_done_booting - Called near the end of core bootup
*
- * Hack to avoid lots of clocksource churn at boot time
+ * Hack to avoid lots of clocksource churn at boot time.
+ * We use fs_initcall because we want this to start before
+ * device_initcall but after subsys_initcall.
*/
static int __init clocksource_done_booting(void)
{
finished_booting = 1;
return 0;
}
-late_initcall(clocksource_done_booting);
+fs_initcall(clocksource_done_booting);
#ifdef CONFIG_CLOCKSOURCE_WATCHDOG
static LIST_HEAD(watchdog_list);
static struct timer_list watchdog_timer;
static DEFINE_SPINLOCK(watchdog_lock);
static cycle_t watchdog_last;
+static unsigned long watchdog_resumed;
+
/*
- * Interval: 0.5sec Treshold: 0.0625s
+ * Interval: 0.5sec Threshold: 0.0625s
*/
#define WATCHDOG_INTERVAL (HZ >> 1)
-#define WATCHDOG_TRESHOLD (NSEC_PER_SEC >> 4)
+#define WATCHDOG_THRESHOLD (NSEC_PER_SEC >> 4)
static void clocksource_ratewd(struct clocksource *cs, int64_t delta)
{
- if (delta > -WATCHDOG_TRESHOLD && delta < WATCHDOG_TRESHOLD)
+ if (delta > -WATCHDOG_THRESHOLD && delta < WATCHDOG_THRESHOLD)
return;
printk(KERN_WARNING "Clocksource %s unstable (delta = %Ld ns)\n",
cs->name, delta);
cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG);
clocksource_change_rating(cs, 0);
- cs->flags &= ~CLOCK_SOURCE_WATCHDOG;
list_del(&cs->wd_list);
}
struct clocksource *cs, *tmp;
cycle_t csnow, wdnow;
int64_t wd_nsec, cs_nsec;
+ int resumed;
spin_lock(&watchdog_lock);
+ resumed = test_and_clear_bit(0, &watchdog_resumed);
+
wdnow = watchdog->read();
wd_nsec = cyc2ns(watchdog, (wdnow - watchdog_last) & watchdog->mask);
watchdog_last = wdnow;
list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) {
csnow = cs->read();
+
+ if (unlikely(resumed)) {
+ cs->wd_last = csnow;
+ continue;
+ }
+
/* Initialized ? */
if (!(cs->flags & CLOCK_SOURCE_WATCHDOG)) {
if ((cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) &&
}
if (!list_empty(&watchdog_list)) {
- __mod_timer(&watchdog_timer,
- watchdog_timer.expires + WATCHDOG_INTERVAL);
+ /*
+ * Cycle through CPUs to check if the CPUs stay
+ * synchronized to each other.
+ */
+ int next_cpu = next_cpu_nr(raw_smp_processor_id(), cpu_online_map);
+
+ if (next_cpu >= nr_cpu_ids)
+ next_cpu = first_cpu(cpu_online_map);
+ watchdog_timer.expires += WATCHDOG_INTERVAL;
+ add_timer_on(&watchdog_timer, next_cpu);
}
spin_unlock(&watchdog_lock);
}
+static void clocksource_resume_watchdog(void)
+{
+ set_bit(0, &watchdog_resumed);
+}
+
static void clocksource_check_watchdog(struct clocksource *cs)
{
struct clocksource *cse;
if (!started && watchdog) {
watchdog_last = watchdog->read();
watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL;
- add_timer(&watchdog_timer);
+ add_timer_on(&watchdog_timer,
+ first_cpu(cpu_online_map));
}
- } else if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) {
+ } else {
+ if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS)
cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES;
if (!watchdog || cs->rating > watchdog->rating) {
watchdog_last = watchdog->read();
watchdog_timer.expires =
jiffies + WATCHDOG_INTERVAL;
- add_timer(&watchdog_timer);
+ add_timer_on(&watchdog_timer,
+ first_cpu(cpu_online_map));
}
}
}
if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS)
cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES;
}
+
+static inline void clocksource_resume_watchdog(void) { }
#endif
/**
+ * clocksource_resume - resume the clocksource(s)
+ */
+void clocksource_resume(void)
+{
+ struct clocksource *cs;
+ unsigned long flags;
+
+ spin_lock_irqsave(&clocksource_lock, flags);
+
+ list_for_each_entry(cs, &clocksource_list, list) {
+ if (cs->resume)
+ cs->resume();
+ }
+
+ clocksource_resume_watchdog();
+
+ spin_unlock_irqrestore(&clocksource_lock, flags);
+}
+
+/**
+ * clocksource_touch_watchdog - Update watchdog
+ *
+ * Update the watchdog after exception contexts such as kgdb so as not
+ * to incorrectly trip the watchdog.
+ *
+ */
+void clocksource_touch_watchdog(void)
+{
+ clocksource_resume_watchdog();
+}
+
+/**
* clocksource_get_next - Returns the selected clocksource
*
*/
spin_unlock_irqrestore(&clocksource_lock, flags);
}
+/**
+ * clocksource_unregister - remove a registered clocksource
+ */
+void clocksource_unregister(struct clocksource *cs)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&clocksource_lock, flags);
+ list_del(&cs->list);
+ if (clocksource_override == cs)
+ clocksource_override = NULL;
+ next_clocksource = select_clocksource();
+ spin_unlock_irqrestore(&clocksource_lock, flags);
+}
+
#ifdef CONFIG_SYSFS
/**
* sysfs_show_current_clocksources - sysfs interface for current clocksource
* Provides sysfs interface for listing current clocksource.
*/
static ssize_t
-sysfs_show_current_clocksources(struct sys_device *dev, char *buf)
+sysfs_show_current_clocksources(struct sys_device *dev,
+ struct sysdev_attribute *attr, char *buf)
{
- char *curr = buf;
+ ssize_t count = 0;
spin_lock_irq(&clocksource_lock);
- curr += sprintf(curr, "%s ", curr_clocksource->name);
+ count = snprintf(buf, PAGE_SIZE, "%s\n", curr_clocksource->name);
spin_unlock_irq(&clocksource_lock);
- curr += sprintf(curr, "\n");
-
- return curr - buf;
+ return count;
}
/**
* clocksource selction.
*/
static ssize_t sysfs_override_clocksource(struct sys_device *dev,
+ struct sysdev_attribute *attr,
const char *buf, size_t count)
{
struct clocksource *ovr = NULL;
- struct list_head *tmp;
size_t ret = count;
int len;
len = strlen(override_name);
if (len) {
+ struct clocksource *cs;
+
ovr = clocksource_override;
/* try to select it: */
- list_for_each(tmp, &clocksource_list) {
- struct clocksource *cs;
-
- cs = list_entry(tmp, struct clocksource, list);
+ list_for_each_entry(cs, &clocksource_list, list) {
if (strlen(cs->name) == len &&
!strcmp(cs->name, override_name))
ovr = cs;
* Provides sysfs interface for listing registered clocksources
*/
static ssize_t
-sysfs_show_available_clocksources(struct sys_device *dev, char *buf)
+sysfs_show_available_clocksources(struct sys_device *dev,
+ struct sysdev_attribute *attr,
+ char *buf)
{
- struct list_head *tmp;
- char *curr = buf;
+ struct clocksource *src;
+ ssize_t count = 0;
spin_lock_irq(&clocksource_lock);
- list_for_each(tmp, &clocksource_list) {
- struct clocksource *src;
-
- src = list_entry(tmp, struct clocksource, list);
- curr += sprintf(curr, "%s ", src->name);
+ list_for_each_entry(src, &clocksource_list, list) {
+ count += snprintf(buf + count,
+ max((ssize_t)PAGE_SIZE - count, (ssize_t)0),
+ "%s ", src->name);
}
spin_unlock_irq(&clocksource_lock);
- curr += sprintf(curr, "\n");
+ count += snprintf(buf + count,
+ max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "\n");
- return curr - buf;
+ return count;
}
/*
* Sysfs setup bits:
*/
-static SYSDEV_ATTR(current_clocksource, 0600, sysfs_show_current_clocksources,
+static SYSDEV_ATTR(current_clocksource, 0644, sysfs_show_current_clocksources,
sysfs_override_clocksource);
-static SYSDEV_ATTR(available_clocksource, 0600,
+static SYSDEV_ATTR(available_clocksource, 0444,
sysfs_show_available_clocksources, NULL);
static struct sysdev_class clocksource_sysclass = {
- set_kset_name("clocksource"),
+ .name = "clocksource",
};
static struct sys_device device_clocksource = {
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff