This patch is for v17.11 and fixes several problems:

1. The cpu frequency set by the user is not exact with
   current kernels, but close. This changes the logic accordingly.
2. The original logic would cause the test to hang indefinitely
   if the submitted job never ends. This adds timeout checks
   on the job wait, plus adds a 1 minute time limit on the job.
3. Improve/simplify the parsing logic.

Bug 5584