----- On May 20, 2021, at 11:54 AM, Norbert Lange nolang...@gmail.com wrote: [...]
>> What prevents you from linking against lttng-ust.so again ? > > I did not poke around enough with Lttng to be confident it wont have > side effects, > I really don't want it active in production. It doesn't seem there is > much public knowledge with Xenomai either. > lttng-ust.so will spawn threads, lttng-ust-tracepoint.so is mostly passive, There is indeed a split between instrumentation and runtime threads done with lttng-ust-tracepoint.so vs lttng-ust.so. I understand that this split is missing for tracelog and tracef, and would be a good thing to have. I would be interested to move the tracelog and tracef implementation from liblttng-ust.so to liblttng-ust-tracepoint.so, even this late in the -rc cycle, because all users of tracelog/tracef need to link against liblttng-ust-tracepoint.so anyway. So moving these symbols should not affect anyone. Can you give it a try and let me know if it works for you ? > So Id want a dynamic tracepoint-provider than i can dlopen (so that > the signal masks are inherited, > I hope you dont touch them). The signals are all blocked for lttng-ust listener threads. We don't modify the signal masks in the tracepoint probes. Not sure which is the target of your question though. > > Of course I could just remove all lttng libraries on the production > system aswell. Still doesnt change that > tracelog and tracef doesnt work that way. Would moving the tracelog/tracef implementation to liblttng-ust-tracepoint.so solve your issues ? > > I implemented my own tracelog/tracef using the normal lttng > tracepoints for now, they totally break on source level with 2.13 > aswell ;) > is it ok if I do this to access them: > > #define TRACEPOINT_DEFINE > #define TRACEPOINT_PROBE_DYNAMIC_LINKAGE > // 2.12 > // #include <lttng/lttng-ust-tracelog.h> > // #include <lttng/lttng-ust-tracef.h> > // 2.13 > #include <lttng/tp/lttng-ust-tracelog.h> > #include <lttng/tp/lttng-ust-tracef.h> > > ie. I would load lttng-ust.so later and can then use those tracepoints. Reimplementing the tracelog/tracef providers is not an intended use-case. I'd very much prefer if we move their implementation to liblttng-ust-tracepoint.so. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
