static DEFINE_SPINLOCK(print_lock);
-static DEFINE_PER_CPU(unsigned long, touch_timestamp);
-static DEFINE_PER_CPU(unsigned long, print_timestamp);
-static DEFINE_PER_CPU(struct task_struct *, watchdog_task);
+static DEFINE_PER_CPU(unsigned long, softlockup_touch_ts); /* touch timestamp */
+static DEFINE_PER_CPU(unsigned long, softlockup_print_ts); /* print timestamp */
+static DEFINE_PER_CPU(struct task_struct *, softlockup_watchdog);
+static DEFINE_PER_CPU(bool, softlock_touch_sync);
static int __read_mostly did_panic;
int __read_mostly softlockup_thresh = 60;
{
int this_cpu = raw_smp_processor_id();
- __raw_get_cpu_var(touch_timestamp) = get_timestamp(this_cpu);
+ __raw_get_cpu_var(softlockup_touch_ts) = get_timestamp(this_cpu);
}
void touch_softlockup_watchdog(void)
{
- __raw_get_cpu_var(touch_timestamp) = 0;
+ __raw_get_cpu_var(softlockup_touch_ts) = 0;
}
EXPORT_SYMBOL(touch_softlockup_watchdog);
+void touch_softlockup_watchdog_sync(void)
+{
+ __raw_get_cpu_var(softlock_touch_sync) = true;
+ __raw_get_cpu_var(softlockup_touch_ts) = 0;
+}
+
void touch_all_softlockup_watchdogs(void)
{
int cpu;
/* Cause each CPU to re-update its timestamp rather than complain */
for_each_online_cpu(cpu)
- per_cpu(touch_timestamp, cpu) = 0;
+ per_cpu(softlockup_touch_ts, cpu) = 0;
}
EXPORT_SYMBOL(touch_all_softlockup_watchdogs);
int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer,
+ void __user *buffer,
size_t *lenp, loff_t *ppos)
{
touch_all_softlockup_watchdogs();
- return proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos);
+ return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
}
/*
void softlockup_tick(void)
{
int this_cpu = smp_processor_id();
- unsigned long touch_timestamp = per_cpu(touch_timestamp, this_cpu);
- unsigned long print_timestamp;
+ unsigned long touch_ts = per_cpu(softlockup_touch_ts, this_cpu);
+ unsigned long print_ts;
struct pt_regs *regs = get_irq_regs();
unsigned long now;
/* Is detection switched off? */
- if (!per_cpu(watchdog_task, this_cpu) || softlockup_thresh <= 0) {
+ if (!per_cpu(softlockup_watchdog, this_cpu) || softlockup_thresh <= 0) {
/* Be sure we don't false trigger if switched back on */
- if (touch_timestamp)
- per_cpu(touch_timestamp, this_cpu) = 0;
+ if (touch_ts)
+ per_cpu(softlockup_touch_ts, this_cpu) = 0;
return;
}
- if (touch_timestamp == 0) {
+ if (touch_ts == 0) {
+ if (unlikely(per_cpu(softlock_touch_sync, this_cpu))) {
+ /*
+ * If the time stamp was touched atomically
+ * make sure the scheduler tick is up to date.
+ */
+ per_cpu(softlock_touch_sync, this_cpu) = false;
+ sched_clock_tick();
+ }
__touch_softlockup_watchdog();
return;
}
- print_timestamp = per_cpu(print_timestamp, this_cpu);
+ print_ts = per_cpu(softlockup_print_ts, this_cpu);
/* report at most once a second */
- if (print_timestamp == touch_timestamp || did_panic)
+ if (print_ts == touch_ts || did_panic)
return;
/* do not print during early bootup: */
* Wake up the high-prio watchdog task twice per
* threshold timespan.
*/
- if (now > touch_timestamp + softlockup_thresh/2)
- wake_up_process(per_cpu(watchdog_task, this_cpu));
+ if (time_after(now - softlockup_thresh/2, touch_ts))
+ wake_up_process(per_cpu(softlockup_watchdog, this_cpu));
/* Warn about unreasonable delays: */
- if (now <= (touch_timestamp + softlockup_thresh))
+ if (time_before_eq(now - softlockup_thresh, touch_ts))
return;
- per_cpu(print_timestamp, this_cpu) = touch_timestamp;
+ per_cpu(softlockup_print_ts, this_cpu) = touch_ts;
spin_lock(&print_lock);
printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %lus! [%s:%d]\n",
- this_cpu, now - touch_timestamp,
+ this_cpu, now - touch_ts,
current->comm, task_pid_nr(current));
print_modules();
print_irqtrace_events(current);
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
- BUG_ON(per_cpu(watchdog_task, hotcpu));
+ BUG_ON(per_cpu(softlockup_watchdog, hotcpu));
p = kthread_create(watchdog, hcpu, "watchdog/%d", hotcpu);
if (IS_ERR(p)) {
printk(KERN_ERR "watchdog for %i failed\n", hotcpu);
return NOTIFY_BAD;
}
- per_cpu(touch_timestamp, hotcpu) = 0;
- per_cpu(watchdog_task, hotcpu) = p;
+ per_cpu(softlockup_touch_ts, hotcpu) = 0;
+ per_cpu(softlockup_watchdog, hotcpu) = p;
kthread_bind(p, hotcpu);
break;
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
- wake_up_process(per_cpu(watchdog_task, hotcpu));
+ wake_up_process(per_cpu(softlockup_watchdog, hotcpu));
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN:
- if (!per_cpu(watchdog_task, hotcpu))
+ if (!per_cpu(softlockup_watchdog, hotcpu))
break;
/* Unbind so it can run. Fall thru. */
- kthread_bind(per_cpu(watchdog_task, hotcpu),
+ kthread_bind(per_cpu(softlockup_watchdog, hotcpu),
cpumask_any(cpu_online_mask));
case CPU_DEAD:
case CPU_DEAD_FROZEN:
- p = per_cpu(watchdog_task, hotcpu);
- per_cpu(watchdog_task, hotcpu) = NULL;
+ p = per_cpu(softlockup_watchdog, hotcpu);
+ per_cpu(softlockup_watchdog, hotcpu) = NULL;
kthread_stop(p);
break;
#endif /* CONFIG_HOTPLUG_CPU */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff