On 12-05-06 01:17 AM, Chuck Tuffli wrote: > Hi - > > I'm investigating the feasibility of replacing some home grown tracing > code with LTTng and am looking for advice from others who have used > LTTng to trace program flow (i.e. trace function entry and exit > points). One of the strengths of LTTng seems to be the ability to > selectively enable tracepoints of interest (much more useful than our > all-or-nothing tracing). To get this type of capability, would I need > to implement an entry and exit tracepoint for each function or is > there a better approach? Any other best practices people would be > willing to share? TIA.
Hi, For now you'd have to create a custom probe for each function entry and exit. There's a feature on the wishlist to use GCC hooks to automatically generate those probes [1]. The end result would be the same, but it would be much less tedious to do the instrumentation part. A Clang plugin was also mentioned previously [2], but I don't think anybody has tried it yet. [1] https://bugs.lttng.org/issues/39 [2] http://lists.lttng.org/pipermail/lttng-dev/2012-April/017787.html Hope this helps, -- Alexandre Montplaisir DORSAL lab, École Polytechnique de Montréal _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
