MFC r214237,214489:

MFC r214237,214489:

Remove mention of non-existant -o flag for debugging options.

Fix CPU load reporting independent of scheduler used.
- Sample CPU usage data from kern.cp_times, this makes for a far more
  accurate and scheduler independent algorithm.
- Rip out the process list scraping that is no longer required.
- Don't update CPU usage sampling on every request, but every 15s
  instead. This makes it impossible for an attacker to hide the CPU load
  by triggering 4 samplings in short succession when the system is idle.
- After reaching the steady-state, the system will always report the
  average CPU load of the last 60 sampled seconds.
- Untangling of call graph.

git-svn-id: svn://svn.freebsd.org/base/stable/8@215774 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f