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authorJozsef Kadlecsik <kadlec@blackhole.kfki.hu>2013-02-21 17:07:14 +0100
committerJozsef Kadlecsik <kadlec@blackhole.kfki.hu>2013-02-21 17:07:14 +0100
commite29371d762df5bb35d2bc434ea266a046e5a0a75 (patch)
treedac4a8db52d92453415f35606130a49e9f32e4ef /kernel/watchdog.c
parent17b14ca25e9cd6c5cd7605941f6120e405a84f8b (diff)
parent894e2ac82bd0029adce7ad6c8d25501fdd82c994 (diff)
Merge branch 'master' of git://1984.lsi.us.es/nf
Diffstat (limited to 'kernel/watchdog.c')
-rw-r--r--kernel/watchdog.c21
1 files changed, 12 insertions, 9 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 9d4c8d5a1f5..75a2ab3d0b0 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -31,6 +31,7 @@
int watchdog_enabled = 1;
int __read_mostly watchdog_thresh = 10;
static int __read_mostly watchdog_disabled;
+static u64 __read_mostly sample_period;
static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts);
static DEFINE_PER_CPU(struct task_struct *, softlockup_watchdog);
@@ -116,7 +117,7 @@ static unsigned long get_timestamp(int this_cpu)
return cpu_clock(this_cpu) >> 30LL; /* 2^30 ~= 10^9 */
}
-static unsigned long get_sample_period(void)
+static void set_sample_period(void)
{
/*
* convert watchdog_thresh from seconds to ns
@@ -125,7 +126,7 @@ static unsigned long get_sample_period(void)
* and hard thresholds) to increment before the
* hardlockup detector generates a warning
*/
- return get_softlockup_thresh() * (NSEC_PER_SEC / 5);
+ sample_period = get_softlockup_thresh() * ((u64)NSEC_PER_SEC / 5);
}
/* Commands for resetting the watchdog */
@@ -275,7 +276,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
wake_up_process(__this_cpu_read(softlockup_watchdog));
/* .. and repeat */
- hrtimer_forward_now(hrtimer, ns_to_ktime(get_sample_period()));
+ hrtimer_forward_now(hrtimer, ns_to_ktime(sample_period));
if (touch_ts == 0) {
if (unlikely(__this_cpu_read(softlockup_touch_sync))) {
@@ -343,6 +344,10 @@ static void watchdog_enable(unsigned int cpu)
{
struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer);
+ /* kick off the timer for the hardlockup detector */
+ hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hrtimer->function = watchdog_timer_fn;
+
if (!watchdog_enabled) {
kthread_park(current);
return;
@@ -351,12 +356,8 @@ static void watchdog_enable(unsigned int cpu)
/* Enable the perf event */
watchdog_nmi_enable(cpu);
- /* kick off the timer for the hardlockup detector */
- hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- hrtimer->function = watchdog_timer_fn;
-
/* done here because hrtimer_start can only pin to smp_processor_id() */
- hrtimer_start(hrtimer, ns_to_ktime(get_sample_period()),
+ hrtimer_start(hrtimer, ns_to_ktime(sample_period),
HRTIMER_MODE_REL_PINNED);
/* initialize timestamp */
@@ -383,7 +384,7 @@ static int watchdog_should_run(unsigned int cpu)
/*
* The watchdog thread function - touches the timestamp.
*
- * It only runs once every get_sample_period() seconds (4 seconds by
+ * It only runs once every sample_period seconds (4 seconds by
* default) to reset the softlockup timestamp. If this gets delayed
* for more than 2*watchdog_thresh seconds then the debug-printout
* triggers in watchdog_timer_fn().
@@ -516,6 +517,7 @@ int proc_dowatchdog(struct ctl_table *table, int write,
if (ret || !write)
return ret;
+ set_sample_period();
if (watchdog_enabled && watchdog_thresh)
watchdog_enable_all_cpus();
else
@@ -537,6 +539,7 @@ static struct smp_hotplug_thread watchdog_threads = {
void __init lockup_detector_init(void)
{
+ set_sample_period();
if (smpboot_register_percpu_thread(&watchdog_threads)) {
pr_err("Failed to create watchdog threads, disabled\n");
watchdog_disabled = -ENODEV;