/** @dir where_func
This is a silly little instrumentation routine to instrument functions
entry by name. It makes use of the SystemTap runtime libraries to break
down the number of times the function by caller. 

It demonstrates kprobes, passing a module parameter, using the print buffer,
and using _stp_print_symbol() to map the addresses back to locations 
in functions.

By default it instruments schedule().

The instrumentation module is built by having the kernel that is going
to be instrumented currently on the machine and doing 
\code
./build
\endcode
The instrumentation is inserted as root with:
\code
/sbin/insmod kprobe_funct_where.ko funct_name=function_name
\endcode
The instrumentation is removed as root with:
\code
/sbin/rmmod kprobe_funct_where
\endcode
-Will Cohen

Note that this module is broken now because we don't pass the module parameter
tp staprun.  FIXME
*/