diff options
| author | Sasha Levin <sasha.levin@oracle.com> | 2014-01-10 12:40:56 +1100 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2014-01-10 12:40:56 +1100 |
| commit | 5bdfd332becd60cb7a12d97e39eabf845c3a9cc9 (patch) | |
| tree | 7fad645cbb64f2f36ad40887ce868a1d35056284 /kernel | |
| parent | 7bcf676f933c00965e06c8456d3ddc1f6932725b (diff) | |
watchdog: trigger all-cpu backtrace when locked up and going to panic
Send an NMI to all CPUs when a lockup is detected and the lockup watchdog
code is configured to panic. This gives us a fairly uptodate snapshot of
all CPUs in the system.
This lets us get stack trace of all CPUs which makes life easier trying to
debug a deadlock, and the NMI doesn't change anything since the next step
is a kernel panic.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/watchdog.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 4431610f049a..373d3e1356b2 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -239,10 +239,12 @@ static void watchdog_overflow_callback(struct perf_event *event, if (__this_cpu_read(hard_watchdog_warn) == true) return; - if (hardlockup_panic) + if (hardlockup_panic) { + trigger_all_cpu_backtrace(); panic("Watchdog detected hard LOCKUP on cpu %d", this_cpu); - else + } else { WARN(1, "Watchdog detected hard LOCKUP on cpu %d", this_cpu); + } __this_cpu_write(hard_watchdog_warn, true); return; @@ -323,8 +325,10 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) else dump_stack(); - if (softlockup_panic) + if (softlockup_panic) { + trigger_all_cpu_backtrace(); panic("softlockup: hung tasks"); + } __this_cpu_write(soft_watchdog_warn, true); } else __this_cpu_write(soft_watchdog_warn, false); |