From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21494 invoked by alias); 17 Jun 2011 15:43:38 -0000 Received: (qmail 21481 invoked by uid 22791); 17 Jun 2011 15:43:36 -0000 X-SWARE-Spam-Status: No, hits=-6.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 17 Jun 2011 15:43:22 +0000 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p5HFhM2S032307 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 17 Jun 2011 11:43:22 -0400 Received: from localhost (vpn1-7-80.ams2.redhat.com [10.36.7.80]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p5HFhLQx016724 for ; Fri, 17 Jun 2011 11:43:21 -0400 Date: Fri, 17 Jun 2011 15:43:00 -0000 From: "Richard W.M. Jones" To: systemtap@sourceware.org Subject: staprun -c deadlocks often Message-ID: <20110617154320.GC18438@amd.home.annexia.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) 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: 2011-q2/txt/msg00299.txt.bz2 systemtap-1.4-9.fc15.x86_64 kernel 2.6.38.7-30.fc15.x86_64 I'm not sure if I'm "doing it wrong", but it appears that the staprun -c option deadlocks for me very frequently. Not always, but at least more often than one time in two. Here is what I'm doing (as root): stap -p4 \ -e 'probe module("ext2").statement ("*@*.c:*") { printf ("%s\n", pp()); }' [stap command prints the module name, used below] staprun -o /tmp/stap -c /bin/ls /home/rjones/.systemtap/cache/44/stap_44fe38ee6f62656645948ce5d275d678_260427.ko As I say, more often than half the time, instead of printing out a directory listing, the staprun command will just hang. Note that the filesystem I'm listing is not ext2, so I don't think the probes themselves have anything to do with it. When it hangs, a process listing shows: 13073 pts/4 Ss 0:00 \_ bash 17930 pts/4 S+ 0:00 | \_ sudo staprun -o /tmp/stap -c /bin/ls /home/rjones/.systemtap/cache/44/stap_44fe38ee6f62656645948ce5d275d678_260427.ko 17931 pts/4 Sl+ 0:00 | \_ /usr/libexec/systemtap/stapio -o /tmp/stap -c /bin/ls /home/rjones/.systemtap/cache/44/stap_44fe38ee6f62656645948ce5d275d678_260427.ko 17932 pts/4 S+ 0:00 | \_ /usr/libexec/systemtap/stapio -o /tmp/stap -c /bin/ls /home/rjones/.systemtap/cache/44/stap_44fe38ee6f62656645948ce5d275d678_260427.ko Note that there is no staprun process, nor any /bin/ls, but two stapio processes have been left around. Any ideas? I had a look at the code in runtime/staprun/mainloop.c but it just looks fiendishly complex ... Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones New in Fedora 11: Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 70 libraries supprt'd http://fedoraproject.org/wiki/MinGW http://www.annexia.org/fedora_mingw