diff options
| author | Varun Wadekar <vwadekar@nvidia.com> | 2013-12-04 17:32:51 +0530 |
|---|---|---|
| committer | Varun Wadekar <vwadekar@nvidia.com> | 2013-12-20 01:48:56 -0800 |
| commit | eef8818f6862b654f08165ae119490a54a9e4a68 (patch) | |
| tree | b19ad342127e43c09f5af287fe341db049e9e575 /kernel | |
| parent | 4d82fe62cf9fbe5d35c417e04dae428c3482a984 (diff) | |
kernel: watchdog: query CPU soft/hard lockup status
Allow system drivers to know if any of the CPUs entered soft/hard
lockup state. This allows the FIQ watchdog timer to stop kicking
the watchdog so that we get callstack for all online CPUs.
Bug 1326082
Change-Id: Id6dbd4074430a13da53cf791a6c877987e9fd1a8
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Reviewed-on: http://git-master/r/338250
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/watchdog.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c index e092e5a6cdd7..274e737a92e6 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -53,6 +53,9 @@ static cpumask_t __read_mostly watchdog_cpus; static DEFINE_PER_CPU(struct perf_event *, watchdog_ev); #endif +static __read_mostly int soft_lockup_detected; +static __read_mostly int hard_lockup_detected; + /* boot commands */ /* * Should we panic when a soft-lockup or hard-lockup occurs: @@ -101,6 +104,11 @@ static int __init nosoftlockup_setup(char *str) __setup("nosoftlockup", nosoftlockup_setup); /* */ +int watchdog_get_lockup_state(void) +{ + return ((soft_lockup_detected << 8) || hard_lockup_detected); +} + /* * Hard-lockup warnings should be triggered after just a few seconds. Soft- * lockups can have false positives under extreme conditions. So we generally @@ -253,6 +261,8 @@ static void watchdog_check_hardlockup_other_cpu(void) if (per_cpu(hard_watchdog_warn, next_cpu) == true) return; + hard_lockup_detected = 1; + if (hardlockup_panic) panic("Watchdog detected hard LOCKUP on cpu %u", next_cpu); else @@ -310,6 +320,8 @@ static void watchdog_overflow_callback(struct perf_event *event, if (is_hardlockup()) { int this_cpu = smp_processor_id(); + hard_lockup_detected = 1; + /* only print hardlockups once */ if (__this_cpu_read(hard_watchdog_warn) == true) return; @@ -391,6 +403,8 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) if (__this_cpu_read(soft_watchdog_warn) == true) return HRTIMER_RESTART; + soft_lockup_detected = 1; + printk(KERN_EMERG "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", smp_processor_id(), duration, current->comm, task_pid_nr(current)); |