Re: [PATCH] tracing: Add task_prctl_unknown tracepoint

[Steven Rostedt]

On Wed, 6 Nov 2024 22:59:25 +0100
Marco Elver <elver@xxxxxxxxxx> wrote:

> 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?

You can run trace-cmd, or cat trace after the run.

-- Steve