QA:Testcase Virtualization XenDomU CPU hotplug

Description

This test case verifies the CPUs can be dynamically added to and removed from Fedora Xen DomU guests.

How to test

1. Shut down the F-11 domU guest.
2. Edit the Xen configuration file for the domU guest to make the "vcpus" parameter equal to the number of CPUs you have in your machine. For instance, if you have a system with 2 dual-core processors, set the vcpus parameter in the guest configuration file to 4.
3. Start up the F-11 domU guest.
4. Once the guest is booted, inside the guest run

   $> getconf _NPROCESSORS_ONLN

   This number should match what you set in the guest configuration file above.
5. Now on the dom0, unplug some vcpus from the guest

   $> xm vcpu-set f11 2

6. Inside the guest, run

   $> getconf _NPROCESSORS_ONLN

   again. This should now be 2.
7. Repeat the above test, varying the number of processors you plug and unplug.
8. Put some load on the guest (for example, a kernel compile), and repeat the above test, varying the number of processors you plug and unplug.

Expected Results

1. The guest should not crash while plugging and unplugging vcpus.
2. There should be no softlockup or other warnings while plugging and unpluggins vcpus.