Added kprobe functional test module to CVS

["Lynch, Rusty" <rusty dot lynch at intel dot com>]

Anil and I were brainstorming last night on how to get our hands around
testing our ia64 kprobes port, and came up with an idea where a kernel
module is created that:

* Contains a suitable complex test function, written in assembly to
ensure we are executing the exact sequences we intended to test

* Contains a test harness that repeatedly calls the test function,
inserting a kprobe in each instruction.  The test function should be
written in a way that it easy to tell if the act of inserting the kprobe
on that instruction alters the instructions behavior.

* For every kprobe that is fired, we collect trace data so that after
the run is complete, we can verify that every probe that should have
fired did fire, and instructions that should not be executed do not
trigger an associated kprobe to fire.

* Can support multiple architectures tweaking the Makefile to look for
files that are prepended with the architecture.  For example, the test
function should be in a file named $(ARCH)_probe_points.S

I have checked in a version in CVS at "patches/functional_kprobe_test"
that we are using to finish up the last few functional pieces missing in
the ia64 port.

To browse via a browser goto:
http://sources.redhat.com/cgi-bin/cvsweb.cgi/patches/functional_kprobe_t
est/?cvsroot=systemtap

    --rusty