Re: [PATCH v2 1/2] tracing: Add task_prctl_unknown tracepoint

[Steven Rostedt]

On Thu,  7 Nov 2024 13:25:47 +0100
Marco Elver <elver@xxxxxxxxxx> 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(
> +		__string(	comm,		task->comm	)

The question is, do we really need comm? From your example, it's redundant:

  test-484     [000] .....   631.748104: task_prctl_unknown: comm=test option=1234 arg2=101 arg3=102 arg4=103 arg5=104
  ^^^^                                                            ^^^^

-- Steve


> +		__field(	int,		option)
> +		__field(	unsigned long,	arg2)
> +		__field(	unsigned long,	arg3)
> +		__field(	unsigned long,	arg4)
> +		__field(	unsigned long,	arg5)
> +	),
> +
> +	TP_fast_assign(
> +		__assign_str(comm);
> +		__entry->option = option;
> +		__entry->arg2 = arg2;
> +		__entry->arg3 = arg3;
> +		__entry->arg4 = arg4;
> +		__entry->arg5 = arg5;
> +	),
> +
> +	TP_printk("comm=%s option=%d arg2=%ld arg3=%ld arg4=%ld arg5=%ld",
> +		  __get_str(comm), __entry->option,
> +		  __entry->arg2, __entry->arg3, __entry->arg4, __entry->arg5)
> +);
> +