Ktap almost gets into 3.13

What you're talking about (performance counter dump every time a tracepoint is hit) should in theory be possible with the raw perf_event interface. Just set up the tracepoint and events to measure and have them "sample" every time the tracepoint is hit. I have no idea what kind of crazy command line you'd need to try to convince the "perf" tool to actually do that though, assuming it were possible.