diff options
| author | Sasha Levin <sasha.levin@oracle.com> | 2013-11-05 16:55:22 +1100 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2013-11-05 16:55:22 +1100 |
| commit | 01b46f9cbbbfb80e5712ea0c61a6d12514fa1784 (patch) | |
| tree | 4d89897181e5f84a03338c263ab638abfbe489fd /kernel | |
| parent | dec36e86dd8a24e3501e156da8ca50b03eb8d517 (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); |