From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27668 invoked by alias); 5 May 2009 15:58:46 -0000 Received: (qmail 27660 invoked by uid 22791); 5 May 2009 15:58:45 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 05 May 2009 15:58:37 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n45FwYCU023471 for ; Tue, 5 May 2009 11:58:35 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n45FwY4Z010723 for ; Tue, 5 May 2009 11:58:34 -0400 Received: from localhost.localdomain (dst61.hsv.redhat.com [172.16.16.175]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n45FwUpP006734; Tue, 5 May 2009 11:58:33 -0400 Message-ID: <4A006227.4020607@redhat.com> Date: Tue, 05 May 2009 15:58:00 -0000 From: David Smith User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Mahesh Jagannath Salgaonkar CC: systemtap@sources.redhat.com Subject: Re: Plain kprobe genearation/bisect script - latest changes References: <49DB15D4.1070508@linux.vnet.ibm.com> <49DE1122.5060806@linux.vnet.ibm.com> In-Reply-To: <49DE1122.5060806@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2009-q2/txt/msg00505.txt.bz2 Mahesh Jagannath Salgaonkar wrote: > Mahesh Jagannath Salgaonkar wrote: >> Hi All, >> >> I have implemented shell scripts that helps me to narrow down a faulty >> probe that causes problem/crash, while debugging systemtap issues. As >> per the discussion in weekly systemtap meeting dated 12th March 2009, >> I am attaching these scripts (kp_bisect.tgz) that may help us in >> identifying probes that can be a potential candidate for blacklist. >> These scripts will help user to extract probes (probe function name) >> from stap generated C module and test plain kprobes/kretprobes >> allowing user to run bisect-like functionality to narrow down to a >> single faulty probe. It does handle ".call" and ".return" probes. >> >> Can someone can take look at these scripts and see if these can be >> used as a base for automating the process of testing kprobes for >> black/white list generation? The file "README.txt" describes the steps >> to use these scripts. >> >> Thanks, >> -Mahesh. > > Please find the modified scripts attached. Modified script to isolate > good probes/bad probes and show all bad probes at the end. Mahesh, I finally found some time to look at this. The nice thing about your scripts is that they are very simple and look like they would do the job. The one thing that the scripts I worked on does differently is that it ends up with 3 lists instead of 2 lists: - a "bad" list - functions that cause crashes - a "good" list - functions that were registered correctly and the kprobe got hit with no problems - an "unknown" list - functions that were registered correctly, but the function wasn't actually called (so we don't really know if a kprobe can be safely used with that function or not) -- David Smith dsmith@redhat.com Red Hat http://www.redhat.com 256.217.0141 (direct) 256.837.0057 (fax)