diff options
| author | Petr Mladek <pmladek@suse.com> | 2021-04-30 08:54:23 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-30 21:20:35 +0300 |
| commit | c9ad17c991492f4390f42598f6ab0531f87eed07 (patch) | |
| tree | 4e5b7a5b3adc06074896a4311da0e17308bcc9d8 /kernel/watchdog.c | |
| parent | 7c0012f522c802d25be102bafe54f333168e6119 (diff) | |
| download | linux-c9ad17c991492f4390f42598f6ab0531f87eed07.tar.xz | |
watchdog: explicitly update timestamp when reporting softlockup
The softlockup situation might stay for a long time or even forever. When
it happens, the softlockup debug messages are printed in regular intervals
defined by get_softlockup_thresh().
There is a mystery. The repeated message is printed after the full
interval that is defined by get_softlockup_thresh(). But the timer
callback is called more often as defined by sample_period. The code looks
like the soflockup should get reported in every sample_period when it was
once behind the thresh.
It works only by chance. The watchdog is touched when printing the stall
report, for example, in printk_stack_address().
Make the behavior clear and predictable by explicitly updating the
timestamp in watchdog_timer_fn() when the report gets printed.
Link: https://lkml.kernel.org/r/20210311122130.6788-3-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/watchdog.c')
| -rw-r--r-- | kernel/watchdog.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 8440e62bfec4..8efd2a8d9f10 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -410,6 +410,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) } } + /* Start period for the next softlockup warning. */ + update_touch_ts(); + pr_emerg("BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", smp_processor_id(), duration, current->comm, task_pid_nr(current)); |