From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25331 invoked by alias); 12 Oct 2006 22:19:10 -0000 Received: (qmail 25323 invoked by uid 22791); 12 Oct 2006 22:19:10 -0000 X-Spam-Status: No, hits=-2.6 required=5.0 tests=AWL,BAYES_00,SPF_PASS X-Spam-Check-By: sourceware.org Received: from e2.ny.us.ibm.com (HELO e2.ny.us.ibm.com) (32.97.182.142) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 12 Oct 2006 22:19:06 +0000 Received: from d01relay04.pok.ibm.com (d01relay04.pok.ibm.com [9.56.227.236]) by e2.ny.us.ibm.com (8.13.8/8.12.11) with ESMTP id k9CMJ46o030281 for ; Thu, 12 Oct 2006 18:19:04 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay04.pok.ibm.com (8.13.6/8.13.6/NCO v8.1.1) with ESMTP id k9CMJ2X6140450 for ; Thu, 12 Oct 2006 18:19:04 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id k9CMJ1wX016593 for ; Thu, 12 Oct 2006 18:19:01 -0400 Received: from [127.0.0.1] (wecm-9-67-57-16.wecm.ibm.com [9.67.57.16]) by d01av04.pok.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id k9CMIuLF016352; Thu, 12 Oct 2006 18:19:01 -0400 Message-ID: <452EBF4A.8000500@us.ibm.com> Date: Thu, 12 Oct 2006 22:19:00 -0000 From: Mike Mason User-Agent: Thunderbird 1.5.0.7 (Windows/20060909) MIME-Version: 1.0 To: Martin Hunt CC: systemtap@sources.redhat.com Subject: Re: stack trace changes References: <1160679497.4762.11.camel@dragon> In-Reply-To: <1160679497.4762.11.camel@dragon> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2006-q4/txt/msg00107.txt.bz2 Thanks for working on this. See comments below... Martin Hunt wrote: > I've checked in a rewrite of the stack trace code. I rewrote i386 and > x86_64 only. ppc64 and ia64 should still work as before, unless I made > any errors while reorganizing the code. I'll test on ppc64 after the build error is fixed in the ppc64 runtine (see bug 3051). > > In 2.6.18 there is code to use DWARF to accurately unwind the stacks. > The new code uses this if available, otherwise it falls back to the > inaccurate unwinder. Some situations like kretprobe trampolines confuse > the unwinder and it does what it can accurately then uses the inaccurate > unwinder. In all cases, it now says when the trace in not accurate. I tested print_backtrace on 2.6.17-1.2187_FC5 on x86_64. I now see a single line(as before) followed by "Inexact backtrace:" and then nothing. Is there no way to get additional stack info on x86_64 kernels earlier than 2.6.18? Just want to know what to expect. I tested on 2.6.18 as well and it appears to work as you described. Thanks again for your efforts. - Mike