module function probe

[Frank Ch. Eigler]

Hi -

> 	I wrote one module named probed.ko after compiled, and the other
> is kprobe module named probing.ko which is to probe some function
> defined in probed.ko module. 
> [...]
> 		#insmod probed.ko
> 		#insmod probing.ko
> 		#rmmod probed.ko
> 		#rmmod probing.ko
> [...]

To manage module reference counts in a way that prevents this problem,
systemtap keeps a file descriptor open on some file under
/sys/module/<PROBED>/.  By using plain insmod, you are giving up this
protection.

- FChE