You can also list all ust events available for tracing via the command "lttng list -u".
Make sure that the application you want to trace is running. On 06/25/2014 10:40 AM, Thibault, Daniel wrote: > ---------------------------------------------------------------------- > Date: Sun, 22 Jun 2014 19:27:31 +0400 > From: Dmitri Shubin <[email protected]> > >> In dtrace it's possible to check if some probe is currently enabled or not >> (to avoid argument preparation for disabled probes). >> But I'm unable to find similar feature in lttng-ust (at least it's not >> mentioned in lttng-ust man page). >> >> Am I missed it or it's not implemented on purpose? > > Use the list command. A command such as 'lttng list <session_name>' will > list the known events and their enabled/disabled status. You can filter the > command's output by specifying a domain (--userspace) and/or a channel > (--channel <channel_name>). For example: > > (begin example) > $ lttng create some_session > Session some_session created. > Traces will be written in /home/username/lttng-traces/ > some_session-20140625-102709 > $ lttng enable-event -u some_event > UST event some_event created in channel channel0 > $ lttng list some_session -u --channel channel0 > Tracing session some_session: [inactive] > Trace path: /home/username/lttng-traces/ some_session-20140625-102709 > > === Domain: UST global === > > Buffer type: per UID > > - channel0: [enabled] > > Attributes: > overwrite mode: 0 > subbuffers size: 131072 > number of subbufers: 4 > switch time interval: 0 > read time interval: 0 > output: mmap() > > Events: > some_event (type: tracepoint) [enabled] > (end example) > > You can take a look at /usr/src/lttng-tools/src/bin/lttng/commands/list.c > to see how the information is obtained. > > 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) > RDDC - Centre de recherches de Valcartier | DRDC - Valcartier Research Centre > 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 > _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
