I think I found: 
static const struct pid_entry tgid_base_stuff[] at fs/proc/base.c has all /proc/[pid] entries.

But unfortunately it does not use create_proc_entry function, and I'm trying to create a new syscall that creates a new proc_entry for the caller process. 
Adding a new element in tgid_base_stuff[] makes the things more complicated than simply call a create_proc_entry function.

Is there another way to do it ?

Mauro Romano Trajber

On Mon, Jan 10, 2011 at 3:18 PM, Mauro Romano Trajber <trajber@gmail.com> wrote:
How can I create a new proc entry under /proc/[pid] ? 
I using create_proc_entry("SOME_FILE", 0644, NULL /* here goes the pid proc entry */); 
Is there any way to get PID directory as a parent proc entry ? How ? 

Thanks,
Mauro