HvGetLogicalProcessorRunTime function

The HvGetLogicalProcessorRunTime function queries for the run time of the logical processor that is associated with the caller's virtual processor.

Syntax

C++


HV_STATUS  HvGetLogicalProcessorRunTime(
  _Out_  PHV_NANO100_TIME GlobalTime,
  _Out_  PHV_NANO100_TIME LocalRunTime,
  _Out_  UINT64 RsvdZ,
  _Out_  PHV_NANO100_TIME HypervisorTime
);

Parameters

GlobalTime [out]: A pointer to an HV_NANO100_TIME variable in which HvGetLogicalProcessorRunTime stores the current global reference time. HV_NANO100_TIME is defined as an unsigned 64-bit (UINT64) value.
LocalRunTime [out]: A pointer to an HV_NANO100_TIME variable in which HvGetLogicalProcessorRunTime stores the run time of the logical processor that is associated with the caller's virtual processor.
RsvdZ [out]: Reserved. Do not use.
HypervisorTime [out]: A pointer to an HV_NANO100_TIME variable in which HvGetLogicalProcessorRunTime stores the amount of time the hypervisor has executed on the logical processor.

Return value

HvGetLogicalProcessorRunTime returns one of the following values. In addition to these values, HvGetLogicalProcessorRunTime can also return one of the values that are specified in Common Hypercall Status Codes.

Return code	Description
HV_STATUS_SUCCESS	HvGetLogicalProcessorRunTime successfully queried for the run time of the logical processor that is associated with the caller's virtual processor.
HV_STATUS_ACCESS_DENIED	The caller's partition does not possess the CPUManagement privilege.

Remarks

HvGetLogicalProcessorRunTime requires that the calling partition possess the CPUManagement privilege. For more information on this privilege and its application, see the HV_PARTITION_PRIVILEGE_MASK union.

For more information about logical processor run time, see Hardware Management Data Types.

Utilization can be computed by calling HvGetLogicalProcessorRunTime twice and then dividing (LocalRunTimen - LocalRunTimen-1) by (GlobalTimen - GlobalTimen-1).

The information that HvGetLogicalProcessorRunTime receives can be used to determine whether the hypervisor is actively scheduling activity on the logical processor or whether the hypervisor is idle and can be placed into a low-power state without negatively impacting the system's performance.

HvGetLogicalProcessorRunTime has the following restriction:

The caller's partition must possess the CPUManagement privilege.

Native Interface

HvGetLogicalProcessorRunTime
	Call Code = 0x0004
Output Parameters
0	GlobalTime (8 bytes)
8	LocalRunTime (8 bytes)
16	RsvdZ (8 bytes)
24	HypervisorTime (8 bytes)

Requirements