From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754084AbcCRQh7 (ORCPT ); Fri, 18 Mar 2016 12:37:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46410 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751645AbcCRQh4 (ORCPT ); Fri, 18 Mar 2016 12:37:56 -0400 Date: Fri, 18 Mar 2016 12:37:48 -0400 From: Don Zickus To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, rostedt@goodmis.org, mingo@kernel.org, tglx@linutronix.de Subject: Re: [PATCH 1/2] watchdog: Fix output Message-ID: <20160318163748.GR64531@redhat.com> References: <20160318152802.407611377@infradead.org> <20160318153022.027826871@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160318153022.027826871@infradead.org> User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 #include @@ -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 > Signed-off-by: Peter Zijlstra (Intel) > --- > 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); > >