-XBT_PRIVATE void TRACE_msg_process_suspend(msg_process_t process);
-XBT_PRIVATE void TRACE_msg_process_resume(msg_process_t process);
-XBT_PRIVATE void TRACE_msg_process_sleep_in(msg_process_t process); // called from msg/gos.c
-XBT_PRIVATE void TRACE_msg_process_sleep_out(msg_process_t process);