From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756801Ab3EHOyB (ORCPT ); Wed, 8 May 2013 10:54:01 -0400 Received: from cantor2.suse.de ([195.135.220.15]:33322 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755832Ab3EHOyA (ORCPT ); Wed, 8 May 2013 10:54:00 -0400 Date: Wed, 08 May 2013 16:54:00 +0200 Message-ID: From: Takashi Iwai To: Andrew Morton Cc: Jean Delvare , linux-kernel , Tejun Heo Subject: Re: [PATCH] idr: Print a stack dump after ida_remove warning In-Reply-To: <20130507163422.7f88f07fc571b49362eb283a@linux-foundation.org> References: <1367746323.4682.750.camel@chaos.site> <20130507163422.7f88f07fc571b49362eb283a@linux-foundation.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/24.2 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org At Tue, 7 May 2013 16:34:22 -0700, Andrew Morton wrote: > > On Sun, 05 May 2013 11:32:03 +0200 Jean Delvare wrote: > > > We print a dump stack after idr_remove warning. This is useful to find > > the faulty piece of code. Let's do the same for ida_remove, as it > > would be equally useful there. > > > > ... > > > > --- linux-3.10-rc0.orig/lib/idr.c 2013-05-05 10:17:03.086198024 +0200 > > +++ linux-3.10-rc0/lib/idr.c 2013-05-05 10:41:11.939134735 +0200 > > @@ -1066,6 +1066,7 @@ void ida_remove(struct ida *ida, int id) > > err: > > printk(KERN_WARNING > > "ida_remove called for id=%d which is not allocated.\n", id); > > + dump_stack(); > > } > > EXPORT_SYMBOL(ida_remove); > > If we're going to do this, we should make that printk a KERN_EMERG or > something, otherwise users might see a stack dump with no explanation > why it occurred. > > We can do all that with plain old WARN(). How does this look? Nice, it reduces even 4 more lines! :) Takashi > > > From: Andrew Morton > Subject: idr-print-a-stack-dump-after-ida_remove-warning-fix > > convert the open-coded printk+dump_stack into WARN() > > Cc: Jean Delvare > Cc: Takashi Iwai > Cc: Tejun Heo > Signed-off-by: Andrew Morton > --- > > lib/idr.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff -puN lib/idr.c~idr-print-a-stack-dump-after-ida_remove-warning-fix lib/idr.c > --- a/lib/idr.c~idr-print-a-stack-dump-after-ida_remove-warning-fix > +++ a/lib/idr.c > @@ -524,9 +524,7 @@ EXPORT_SYMBOL(idr_alloc_cyclic); > > static void idr_remove_warning(int id) > { > - printk(KERN_WARNING > - "idr_remove called for id=%d which is not allocated.\n", id); > - dump_stack(); > + WARN(1, "idr_remove called for id=%d which is not allocated.\n", id); > } > > static void sub_remove(struct idr *idp, int shift, int id) > @@ -1064,9 +1062,7 @@ void ida_remove(struct ida *ida, int id) > return; > > err: > - printk(KERN_WARNING > - "ida_remove called for id=%d which is not allocated.\n", id); > - dump_stack(); > + WARN(1, "ida_remove called for id=%d which is not allocated.\n", id); > } > EXPORT_SYMBOL(ida_remove); > > _ >