We should support multiple target processes in stapdyn. This primarily means following fork/exec process children from the initial target, but it could also mean allowing multiple -c/-x targets, if we want. We'll need shared memory between targets, at least for global variables (including per-thread stats memory, so anyone can aggregate). Any events that are not process specific (e.g. begin, end, timers) can run in the stapdyn process, like they are now for the case with no target process.
There have been many commits as baby steps towards shared memory, but commit f4d70a33 is the first that's finally running across processes. As planned, begin/end/timers are now running directly in stapdyn, while uprobes/utrace-like probes run in the target process. Next is to follow fork/exec to really have multiple process targets.
Forks should work as of commits 72100304 and 964519ac. Exec is started in commit b9babf95, but that still has issues to work out.