diff options
| author | Petr Mladek <pmladek@suse.com> | 2021-04-29 22:54:23 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-05-19 10:56:20 +0200 |
| commit | 04573e92b1d05b22ade4762e1caa467d635edb37 (patch) | |
| tree | f37d4433a792bf40d459b5bc6f1be88ebc2e24ec /kernel/watchdog.c | |
| parent | 15cfe627b05a3433babe2e8839cfd81a9cc60189 (diff) | |
watchdog: explicitly update timestamp when reporting softlockup
[ Upstream commit c9ad17c991492f4390f42598f6ab0531f87eed07 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.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)); |