On Fri, Mar 18, 2016 at 04:28:03PM +0100, Peter Zijlstra wrote:
> The pr_crap() functions generate idiotic output; use printk().
>
> Broken output:
>
> [ 3538.718135] NMI watchdog: BUG: soft lockup - CPU#2 stuck for 22s!
> [perf_fuzzer:2646]
> [ 3383.233583] NMI watchdog: Watchdog detected hard LOCKUP on cpu 27
>
> Fixed output:
>
> [14180.328194] BUG: soft lockup - CPU#2 stuck for 23s! [perf_fuzzer:13650]
> [ 1064.914925] BUG: NMI Watchdog detected hard LOCKUP on cpu 11
Would something like this be a better patch?
Cheers,
Don
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index b3ace6e..e3302a0 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -9,7 +9,7 @@
* to those contributors as well.
*/
-#define pr_fmt(fmt) "NMI watchdog: " fmt
+#define pr_fmt(fmt) "Lockup detector: " fmt
#include <linux/mm.h>
#include <linux/cpu.h>
@@ -350,7 +350,7 @@ static void watchdog_overflow_callback(struct perf_event
*event,
if (__this_cpu_read(hard_watchdog_warn) == true)
return;
- pr_emerg("Watchdog detected hard LOCKUP on cpu %d", this_cpu);
+ pr_emerg("Detected hard LOCKUP on cpu %d", this_cpu);
print_modules();
print_irqtrace_events(current);
if (regs)
@@ -467,7 +467,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct
hrtimer *hrtimer)
}
}
- pr_emerg("BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
+ pr_emerg("Detected soft lockup - CPU#%d stuck for %us!
[%s:%d]\n",
smp_processor_id(), duration,
current->comm, task_pid_nr(current));
__this_cpu_write(softlockup_task_ptr_saved, current);
>
> Cc: Don Zickus <dzic...@redhat.com>
> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
> ---
> kernel/watchdog.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> --- a/kernel/watchdog.c
> +++ b/kernel/watchdog.c
> @@ -350,7 +350,7 @@ static void watchdog_overflow_callback(s
> if (__this_cpu_read(hard_watchdog_warn) == true)
> return;
>
> - pr_emerg("Watchdog detected hard LOCKUP on cpu %d", this_cpu);
> + printk(KERN_EMERG "BUG: NMI detected hard LOCKUP on cpu %d",
> this_cpu);
> print_modules();
> print_irqtrace_events(current);
> if (regs)
> @@ -467,7 +467,7 @@ static enum hrtimer_restart watchdog_tim
> }
> }
>
> - pr_emerg("BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
> + printk(KERN_EMERG "BUG: soft lockup - CPU#%d stuck for %us!
> [%s:%d]\n",
> smp_processor_id(), duration,
> current->comm, task_pid_nr(current));
> __this_cpu_write(softlockup_task_ptr_saved, current);
>
>
