From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964872Ab2FHVjb (ORCPT ); Fri, 8 Jun 2012 17:39:31 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34942 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751091Ab2FHVj3 (ORCPT ); Fri, 8 Jun 2012 17:39:29 -0400 Date: Fri, 8 Jun 2012 14:39:28 -0700 From: Andrew Morton To: Don Zickus Cc: LKML , nzimmer@sgi.com, joe@perches.com Subject: Re: [PATCH v2] watchdog: Quiet down the boot messages Message-Id: <20120608143928.f84822cc.akpm@linux-foundation.org> In-Reply-To: <1339189389-731-1-git-send-email-dzickus@redhat.com> References: <1339189389-731-1-git-send-email-dzickus@redhat.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 8 Jun 2012 17:03:09 -0400 Don Zickus wrote: > A bunch of bugzillas have complained how noisy the nmi_watchdog is during > boot-up especially with its expected failure cases (like virt and bios > resource contention). > > This is my attempt to quiet them down and keep it less confusing for the end > user. What I did is print the message for cpu0 and save it for future > comparisons. If future cpus have an identical message as cpu0, then don't > print the redundant info. However, if a future cpu has a different message, > happily print that loudly. > > Before the change, you would see something like: > > ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 > CPU0: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz stepping 0a > Performance Events: PEBS fmt0+, Core2 events, Intel PMU driver. > ... version: 2 > ... bit width: 40 > ... generic registers: 2 > ... value mask: 000000ffffffffff > ... max period: 000000007fffffff > ... fixed-purpose events: 3 > ... event mask: 0000000700000003 > NMI watchdog enabled, takes one hw-pmu counter. > Booting Node 0, Processors #1 > NMI watchdog enabled, takes one hw-pmu counter. > #2 > NMI watchdog enabled, takes one hw-pmu counter. > #3 Ok. > NMI watchdog enabled, takes one hw-pmu counter. > Brought up 4 CPUs > Total of 4 processors activated (22607.24 BogoMIPS). > > After the change, it is simplified to: > > ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 > CPU0: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz stepping 0a > Performance Events: PEBS fmt0+, Core2 events, Intel PMU driver. > ... version: 2 > ... bit width: 40 > ... generic registers: 2 > ... value mask: 000000ffffffffff > ... max period: 000000007fffffff > ... fixed-purpose events: 3 > ... event mask: 0000000700000003 > NMI watchdog enabled, takes one hw-pmu counter. > Booting Node 0, Processors #1 #2 #3 Ok. > Brought up 4 CPUs What is the behaviour of this change at suspend/resume time? > + if (cpu ==0 || cpu0_err) Please use checkpatch. It's free!