SQL>  oradebug doc event filter callstack

callstack: filter to only fire an event when a function is on the stack.If the nofname option is used, then the event is fired only when the function is not on the stack

Usage
-------
{callstack:  fname           <string>[64],
             fprefix         <string>[64],
             maxdepth        <ub4>,
             nofname         <string>[64] }