> Date: Mon, 25 Nov 2013 12:00:14 -0500 > From: J?r?mie Galarneau <[email protected]>
>> Aha! There is one crucial mistake in the ibm.com document: he installs >> the packages in the wrong order. lttng-tools must be installed AFTER >> lttng-modules and lttng-ust. lttng-modules can be installed before, during >> or after lttng-ust, but userspace-rcu must be installed before lttng-ust. >> The problem is that the configure of lttng-tools detects the presence or >> absence of lttng-modules and also detects the presence or absence of >> lttng-ust, and adjusts to both. By installing lttng-tools before >> lttng-modules, you've built an lttng-tools set that CANNOT be used to trace >> the kernel. >> >> So, try again from scratch, making sure to install lttng-tools last. > > lttng-tools checks for kernel modules at run time, not at configure time. You > can safely install lttng-modules after lttng-tools and still use kernel > tracing. > > Regards, > Jérémie Dang, you're right. The build of lttng-tools reacts to the presence or absence of lttng-ust, but is indifferent to the presence or absence of lttng-modules. (Only liblttng-ctl.a is different, probably some internal timestamps or some such) > klaus@ubuntu:~$ sudo lttng -vvv start > DEBUG2 [2854/2854]: Config file path found: /home/klaus (in > get_session_name() at utils.c:57) > DEBUG1 [2854/2854]: Session name found: auto-20131124-091639 (in > get_session_name() at utils.c:58) > DEBUG1 [2854/2854]: Starting tracing for session auto-20131124-091639 (in > start_tracing() at commands/start.c:81) > DEBUG1 [2854/2854]: LSM cmd type : 16 (in send_session_msg() at > lttng-ctl.c:131) > 'ctrl c' > klaus@ubuntu:~$ Let's try to identify the module responsible. First, make sure lttng-sessiond is NOT running. Then, do this in one shell: $ sudo -H lttng-sessiond -vvv It should fail after loading one of the modules. You can also try: $ sudo -H lttng-sessiond -vvv --no-kernel In which case you should be able to do any lttng command except those involving the kernel. For example, 'lttng list -u'. Daniel U. Thibault Protection des systèmes et contremesures (PSC) | Systems Protection & Countermeasures (SPC) Cyber sécurité pour les missions essentielles (CME) | Mission Critical Cyber Security (MCCS) R & D pour la défense Canada - Valcartier (RDDC Valcartier) | Defence R&D Canada - Valcartier (DRDC Valcartier) 2459 route de la Bravoure Québec QC G3J 1X5 CANADA Vox : (418) 844-4000 x4245 Fax : (418) 844-4538 NAC : 918V QSDJ <http://www.travelgis.com/map.asp?addr=918V%20QSDJ> Gouvernement du Canada | Government of Canada <http://www.valcartier.drdc-rddc.gc.ca/> _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
