Long time no see!
Having my thesis redaction on hold, for the past week, I've worked on implementing the support for lttng-ust 2.0 into lttng-tools. Skipping the details of complex data structure and chasing racy bugs, UST tracing is now working with the basic execution flow:
$ lttng create s1
$ lttng enable-channel chan1 -u
$ lttng enable-event <event_name_in_code> -u -c chan1
$ lttng start
$ lttng stop
and with babeltrace it is readable.
Note that we can also enable channels and events before tracing has begun or the application has even register. The "-u" flag is the UST global domain meaning that every command pass to this domain will affect all applications for a tracing session.
Work is ongoing to stabilize and add features to lttng-ust support.
A huge thanks to the Ericsson's guys reporting a lot of issues and for Mathieu Desnoyers to fix them in a time span of [0, 5[ minutes :)