#ifdef CONFIG_SOFTLOCKUP_DETECTOR
+#define SOFTLOCKUP_RESET ULONG_MAX
+
/* Global variables, exported for sysctl */
unsigned int __read_mostly softlockup_panic =
CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE;
static DEFINE_PER_CPU(bool, softlockup_touch_sync);
static DEFINE_PER_CPU(bool, soft_watchdog_warn);
static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts);
-static DEFINE_PER_CPU(unsigned long, soft_lockup_hrtimer_cnt);
-static DEFINE_PER_CPU(struct task_struct *, softlockup_task_ptr_saved);
static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts_saved);
static unsigned long soft_lockup_nmi_warn;
* Preemption can be enabled. It doesn't matter which CPU's timestamp
* gets zeroed here, so use the raw_ operation.
*/
- raw_cpu_write(watchdog_touch_ts, 0);
+ raw_cpu_write(watchdog_touch_ts, SOFTLOCKUP_RESET);
}
notrace void touch_softlockup_watchdog(void)
* the softlockup check.
*/
for_each_cpu(cpu, &watchdog_allowed_mask)
- per_cpu(watchdog_touch_ts, cpu) = 0;
+ per_cpu(watchdog_touch_ts, cpu) = SOFTLOCKUP_RESET;
wq_watchdog_touch(-1);
}
void touch_softlockup_watchdog_sync(void)
{
__this_cpu_write(softlockup_touch_sync, true);
- __this_cpu_write(watchdog_touch_ts, 0);
+ __this_cpu_write(watchdog_touch_ts, SOFTLOCKUP_RESET);
}
static int is_softlockup(unsigned long touch_ts)
*/
static int softlockup_fn(void *data)
{
- __this_cpu_write(soft_lockup_hrtimer_cnt,
- __this_cpu_read(hrtimer_interrupts));
__touch_watchdog();
complete(this_cpu_ptr(&softlockup_completion));
/* .. and repeat */
hrtimer_forward_now(hrtimer, ns_to_ktime(sample_period));
- if (touch_ts == 0) {
+ if (touch_ts == SOFTLOCKUP_RESET) {
if (unlikely(__this_cpu_read(softlockup_touch_sync))) {
/*
* If the time stamp was touched atomically
return HRTIMER_RESTART;
/* only warn once */
- if (__this_cpu_read(soft_watchdog_warn) == true) {
- /*
- * When multiple processes are causing softlockups the
- * softlockup detector only warns on the first one
- * because the code relies on a full quiet cycle to
- * re-arm. The second process prevents the quiet cycle
- * and never gets reported. Use task pointers to detect
- * this.
- */
- if (__this_cpu_read(softlockup_task_ptr_saved) !=
- current) {
- __this_cpu_write(soft_watchdog_warn, false);
- __touch_watchdog();
- }
+ if (__this_cpu_read(soft_watchdog_warn) == true)
return HRTIMER_RESTART;
- }
if (softlockup_all_cpu_backtrace) {
/* Prevent multiple soft-lockup reports if one cpu is already
pr_emerg("BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
smp_processor_id(), duration,
current->comm, task_pid_nr(current));
- __this_cpu_write(softlockup_task_ptr_saved, current);
print_modules();
print_irqtrace_events(current);
if (regs)