On Tue, 5 Nov 2024 at 18:02, Steven Rostedt <[email protected]> wrote: > > On Tue, 5 Nov 2024 17:53:53 +0100 > Marco Elver <[email protected]> wrote: > > > > > +/** > > > > + * task_prctl_unknown - called on unknown prctl() option > > > > + * @task: pointer to the current task > > > > + * @option: option passed > > > > + * @arg2: arg2 passed > > > > + * @arg3: arg3 passed > > > > + * @arg4: arg4 passed > > > > + * @arg5: arg5 passed > > > > + * > > > > + * Called on an unknown prctl() option. > > > > + */ > > > > +TRACE_EVENT(task_prctl_unknown, > > > > + > > > > + TP_PROTO(struct task_struct *task, int option, unsigned long > > > > arg2, unsigned long arg3, > > > > + unsigned long arg4, unsigned long arg5), > > > > + > > > > + TP_ARGS(task, option, arg2, arg3, arg4, arg5), > > > > + > > > > + TP_STRUCT__entry( > > > > + __field( pid_t, pid ) > > > > > > Why record the pid that is already recorded by the event header? > > > > To keep in style with the other "task" tracepoints above. I can > > certainly do without - it does seem unnecessary. > > Hmm, new_task, pid is different than the creator. But rename is pointless > to record pid. I would get rid of it here, especially since it also creates > a hole in the event (three int fields followed by a long). > > > > > To cleanup, do we want to remove "pid=" from the other tracepoints in > > this file as well (in another patch). Or does this potentially break > > existing users? > > We can't from task_newtask as that's the pid of the task that's being > created. In other words, it's very relevant. The task_rename could have its > pid field dropped.
Ack - will do. > > > > > > + __string( comm, task->comm ) > > > > > > I'm also surprised that the comm didn't show in the trace_pipe. > > > > Any config options or tweaks needed to get it to show more reliably? > > > > > I've > > > updated the code so that it should usually find it. But saving it here may > > > not be a big deal. > > How did you start it? Because it appears reliable for me. Very normally from bash. Maybe my env is broken in other ways, I'll dig a little.
