From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932152AbWDRRdD (ORCPT ); Tue, 18 Apr 2006 13:33:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932181AbWDRRdD (ORCPT ); Tue, 18 Apr 2006 13:33:03 -0400 Received: from ms-smtp-03.nyroc.rr.com ([24.24.2.57]:63726 "EHLO ms-smtp-03.nyroc.rr.com") by vger.kernel.org with ESMTP id S932152AbWDRRdC (ORCPT ); Tue, 18 Apr 2006 13:33:02 -0400 Subject: Re: Question on Schedule and Preemption From: Steven Rostedt To: Liu haixiang Cc: Andreas Mohr , linux-kernel@vger.kernel.org In-Reply-To: References: <20060418091724.GA7258@rhlx01.fht-esslingen.de> <1145372205.17085.123.camel@localhost.localdomain> Content-Type: text/plain Date: Tue, 18 Apr 2006 13:32:56 -0400 Message-Id: <1145381576.17085.138.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.4.2.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2006-04-19 at 01:21 +0800, Liu haixiang wrote: > 2006/4/18, Steven Rostedt : Damn! I used my work email account to send that. I try to keep the spam down on that account, so I don't publish it as much. Darn Evolution keeps picking the wrong account. > > On Tue, 2006-04-18 at 20:55 +0800, Liu haixiang wrote: > > > > Well according to your output, it was the task "TURNER0" with the pid > > 611. After you recompile the kernel with CONFIG_FRAME_POINTERS you will > > need to follow the stack trace and see what function turned off > > preemption. This can happen calling a spin_lock and not unlocking it > > before calling something that would schedule. > > > > If it's true, it is a great help for me. > > > If you also turn on in "Kernel Hacking" -> "Compile the kernel with > > debug info", you can then do a "gdb vmlinux" in the root directory of > > the compile, and pass in the stack address with the command > > "li *0xc042382e" to show where that function would return. (replace the > > c042382e with the location you are looking for). > > > > Also, what arch are you using to get a 0x04000000 in the preempt_count > > (the 0x1 is the depth). Of course I'm looking at 2.6.17-rc1 and not the > > one you are using. Hmm, your arch may not even support frame pointers. > > > > -- Steve > > > > The arch is SH4. Well I just tried a "make ARCH=sh menuconfig" and the CONFIG_FRAME_POINTERS option is there. Whether it makes a difference or not, I haven't the foggiest clue. -- Steve