Add nvmlDeviceHandle function to Device interface

This change allows the underlying device handle to be returned
without relying on type-casting.

Signed-off-by: Evan Lezar <elezar@nvidia.com>

pkg/nvml/device.go

@@ -22,6 +22,11 @@ type nvmlDevice nvml.Device
 
 var _ Device = (*nvmlDevice)(nil)
 
+// nvmlDeviceHandle returns a pointer to the underlying device.
+func (d nvmlDevice) nvmlDeviceHandle() *nvml.Device {
+	return (*nvml.Device)(&d)
+}
+
 // GetIndex returns the index of a Device
 func (d nvmlDevice) GetIndex() (int, Return) {
 	i, r := nvml.Device(d).GetIndex()
@@ -181,12 +186,12 @@ func (d nvmlDevice) GetSupportedEventTypes() (uint64, Return) {
 
 // GetTopologyCommonAncestor retrieves the common ancestor for two devices.
 func (d nvmlDevice) GetTopologyCommonAncestor(o Device) (GpuTopologyLevel, Return) {
-	other, ok := o.(nvmlDevice)
+	other := o.nvmlDeviceHandle()
-	if !ok {
+	if other == nil {
 		return 0, ERROR_INVALID_ARGUMENT
 	}
 
-	l, r := nvml.Device(d).GetTopologyCommonAncestor(nvml.Device(other))
+	l, r := nvml.Device(d).GetTopologyCommonAncestor(*other)
 	return GpuTopologyLevel(l), Return(r)
 }
 

pkg/nvml/device_mock.go

@@ -4,6 +4,7 @@
 package nvml
 
 import (
+	"github.com/NVIDIA/go-nvml/pkg/nvml"
 	"sync"
 )
 
@@ -101,6 +102,9 @@ var _ Device = &DeviceMock{}
 //			SetMigModeFunc: func(Mode int) (Return, Return) {
 //				panic("mock out the SetMigMode method")
 //			},
+//			nvmlDeviceHandleFunc: func() *nvml.Device {
+//				panic("mock out the nvmlDeviceHandle method")
+//			},
 //		}
 //
 //		// use mockedDevice in code that requires Device
@@ -192,6 +196,9 @@ type DeviceMock struct {
 	// SetMigModeFunc mocks the SetMigMode method.
 	SetMigModeFunc func(Mode int) (Return, Return)
 
+	// nvmlDeviceHandleFunc mocks the nvmlDeviceHandle method.
+	nvmlDeviceHandleFunc func() *nvml.Device
+
 	// calls tracks calls to the methods.
 	calls struct {
 		// CreateGpuInstanceWithPlacement holds details about calls to the CreateGpuInstanceWithPlacement method.
@@ -304,6 +311,9 @@ type DeviceMock struct {
 			// Mode is the Mode argument value.
 			Mode int
 		}
+		// nvmlDeviceHandle holds details about calls to the nvmlDeviceHandle method.
+		nvmlDeviceHandle []struct {
+		}
 	}
 	lockCreateGpuInstanceWithPlacement     sync.RWMutex
 	lockGetArchitecture                    sync.RWMutex
@@ -333,6 +343,7 @@ type DeviceMock struct {
 	lockIsMigDeviceHandle                  sync.RWMutex
 	lockRegisterEvents                     sync.RWMutex
 	lockSetMigMode                         sync.RWMutex
+	locknvmlDeviceHandle                   sync.RWMutex
 }
 
 // CreateGpuInstanceWithPlacement calls CreateGpuInstanceWithPlacementFunc.
@@ -1153,3 +1164,30 @@ func (mock *DeviceMock) SetMigModeCalls() []struct {
 	mock.lockSetMigMode.RUnlock()
 	return calls
 }
+
+// nvmlDeviceHandle calls nvmlDeviceHandleFunc.
+func (mock *DeviceMock) nvmlDeviceHandle() *nvml.Device {
+	if mock.nvmlDeviceHandleFunc == nil {
+		panic("DeviceMock.nvmlDeviceHandleFunc: method is nil but Device.nvmlDeviceHandle was just called")
+	}
+	callInfo := struct {
+	}{}
+	mock.locknvmlDeviceHandle.Lock()
+	mock.calls.nvmlDeviceHandle = append(mock.calls.nvmlDeviceHandle, callInfo)
+	mock.locknvmlDeviceHandle.Unlock()
+	return mock.nvmlDeviceHandleFunc()
+}
+
+// nvmlDeviceHandleCalls gets all the calls that were made to nvmlDeviceHandle.
+// Check the length with:
+//
+//	len(mockedDevice.nvmlDeviceHandleCalls())
+func (mock *DeviceMock) nvmlDeviceHandleCalls() []struct {
+} {
+	var calls []struct {
+	}
+	mock.locknvmlDeviceHandle.RLock()
+	calls = mock.calls.nvmlDeviceHandle
+	mock.locknvmlDeviceHandle.RUnlock()
+	return calls
+}

pkg/nvml/types.go

@@ -68,6 +68,8 @@ type Device interface {
 	IsMigDeviceHandle() (bool, Return)
 	RegisterEvents(uint64, EventSet) Return
 	SetMigMode(Mode int) (Return, Return)
+	// nvmlDeviceHandle returns a pointer to the underlying NVML device.
+	nvmlDeviceHandle() *nvml.Device
 }
 
 // GpuInstance defines the functions implemented by a GpuInstance