NdisGroupActiveProcessorCount function (ndis.h)

Article
02/22/2024

The NdisGroupActiveProcessorCount function returns the number of processors that are currently active in a specified group.

Syntax

ULONG NdisGroupActiveProcessorCount(
  USHORT Group
);

Parameters

Group

A USHORT value that identifies a processor group in the local computer system.

Return value

NdisGroupActiveProcessorCount returns a ULONG value for the number of processors that are active in the group that is specified in the Group parameter. The number of processors is a zero-based value.

If the Group parameter is ALL_PROCESSOR_GROUPS, NdisGroupActiveProcessorCount returns the number of active processors in the local computer.

Remarks

An NDIS driver might call the NdisGroupActiveProcessorCount function during initialization before it allocates resources.

The processor count that NdisGroupActiveProcessorMask returns can change at runtime on SKUs that support hot-add functionality for CPUs.

Note NDIS drivers should not use the NdisSystemProcessorCount function to retrieve the number of processors that are currently active. Also, NDIS 6.20 drivers should not use the NdisSystemActiveProcessorCount function because it only returns the processor count and provides the affinity mask as an out parameter, for processor group 0.

To obtain an active affinity mask, call the NdisGroupActiveProcessorMask function.

To obtain the maximum number of processors in a group, call the NdisGroupMaxProcessorCount function.

Requirements

Requirement	Value
Minimum supported client	Supported in NDIS 6.20 and later.
Target Platform	Universal
Header	ndis.h (include Ndis.h)
Library	Ndis.lib
IRQL	Any level