What:		/sys/hypervisor/pmu/pmu_mode
Date:		August 2015
KernelVersion:	4.3
Contact:	Boris Ostrovsky <boris.ostrovsky@oracle.com>
Description:
		Describes mode that Xen's performance-monitoring unit (PMU)
		uses. Accepted values are
			"off"  -- PMU is disabled
			"self" -- The guest can profile itself
			"hv"   -- The guest can profile itself and, if it is
				  privileged (e.g. dom0), the hypervisor
			"all" --  The guest can profile itself, the hypervisor
				  and all other guests. Only available to
				  privileged guests.

What:           /sys/hypervisor/pmu/pmu_features
Date:           August 2015
KernelVersion:  4.3
Contact:        Boris Ostrovsky <boris.ostrovsky@oracle.com>
Description:
		Describes Xen PMU features (as an integer). A set bit indicates
		that the corresponding feature is enabled. See
		include/xen/interface/xenpmu.h for available features