On Wed, Nov 26, 2014 at 11:59 AM, <[email protected]> wrote: > > Hello, right now I am reading the LTTng documentation and I am at the point > with the "tutorial" for adding a tracepoint to the usb_probe_device(). I > updated the files as instructed, rebuilt the kernel and bootet it, but the > "/sys/kernel/debug/tracing/events/hello" directory wasnt created. It exists > up to the debug directory, but the directory itself is empty. What could > have gone wrong? Is this directory necessary? I still followed the other > instructions and I was able to trace the USB event but I am curios about the > directory.
No, this directory is not needed for LTTng to work, as you noticed yourself. It's only a simple way to confirm your kernel TRACE_EVENT() tracepoints exist using Ftrace. My guess is that debugfs is not mounted (usually mounted at /sys/kernel/debug) on your system. But do not waste your time fixing this, as you're able to record USB events with LTTng. > Furthermore, I am planning to instrument an RTAI kernel (for my > Bachelorthesis), so I can trace it with LTTng. Is it even possible with > these methods? I'll let others answer this as I never had the chance to have fun with RTAI ;-) > > Thank you for your time! > > PS: > I am using an RTAI patched 2.6.38.8 linux kernel with debian > > > _______________________________________________ > 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
