Re: [PATCH] tracing: Add task_prctl_unknown tracepoint

From: Marco Elver
Date: Wed Nov 06 2024 - 17:00:09 EST


On Wed, 6 Nov 2024 at 22:23, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
...
> > That's pretty much it. I've attached my kernel config just in case I
> > missed something.
>
> OK, it's because you are using trace_pipe (which by the way should not be
> used for anything serious). The read of trace_pipe flushes the buffer
> before the task is scheduled out and the comm saved, so it prints the
> "<...>". If you instead do the cat of trace_pipe *after* running the
> command, you'll see the comm.
>
> So this is just because you are using the obsolete trace_pipe.

I see, thanks for clarifying. I always felt for quick testing it
serves its purpose - anything equally simple you recommend for testing
but doesn't suffer from this problem?

Thanks,
-- Marco