CUDA Driver API :: CUDA Toolkit Documentation

4.11. Memory Management

This section describes the memory management functions of the low-level CUDA driver application programming interface.

Functions

CUresult cuArray3DCreate ( CUarray* pHandle, const CUDA_ARRAY3D_DESCRIPTOR* pAllocateArray ): Creates a 3D CUDA array.
CUresult cuArray3DGetDescriptor ( CUDA_ARRAY3D_DESCRIPTOR* pArrayDescriptor, CUarray hArray ): Get a 3D CUDA array descriptor.
CUresult cuArrayCreate ( CUarray* pHandle, const CUDA_ARRAY_DESCRIPTOR* pAllocateArray ): Creates a 1D or 2D CUDA array.
CUresult cuArrayDestroy ( CUarray hArray ): Destroys a CUDA array.
CUresult cuArrayGetDescriptor ( CUDA_ARRAY_DESCRIPTOR* pArrayDescriptor, CUarray hArray ): Get a 1D or 2D CUDA array descriptor.
CUresult cuDeviceGetByPCIBusId ( CUdevice* dev, const char* pciBusId ): Returns a handle to a compute device.
CUresult cuDeviceGetPCIBusId ( char* pciBusId, int len, CUdevice dev ): Returns a PCI Bus Id string for the device.
CUresult cuIpcCloseMemHandle ( CUdeviceptr dptr ): Close memory mapped with cuIpcOpenMemHandle.
CUresult cuIpcGetEventHandle ( CUipcEventHandle* pHandle, CUevent event ): Gets an interprocess handle for a previously allocated event.
CUresult cuIpcGetMemHandle ( CUipcMemHandle* pHandle, CUdeviceptr dptr ): Gets an interprocess memory handle for an existing device memory allocation.
CUresult cuIpcOpenEventHandle ( CUevent* phEvent, CUipcEventHandle handle ): Opens an interprocess event handle for use in the current process.
CUresult cuIpcOpenMemHandle ( CUdeviceptr* pdptr, CUipcMemHandle handle, unsigned int Flags ): Opens an interprocess memory handle exported from another process and returns a device pointer usable in the local process.
CUresult cuMemAlloc ( CUdeviceptr* dptr, size_t bytesize ): Allocates device memory.
CUresult cuMemAllocHost ( void** pp, size_t bytesize ): Allocates page-locked host memory.
CUresult cuMemAllocManaged ( CUdeviceptr* dptr, size_t bytesize, unsigned int flags ): Allocates memory that will be automatically managed by the Unified Memory system.
CUresult cuMemAllocPitch ( CUdeviceptr* dptr, size_t* pPitch, size_t WidthInBytes, size_t Height, unsigned int ElementSizeBytes ): Allocates pitched device memory.
CUresult cuMemFree ( CUdeviceptr dptr ): Frees device memory.
CUresult cuMemFreeHost ( void* p ): Frees page-locked host memory.
CUresult cuMemGetAddressRange ( CUdeviceptr* pbase, size_t* psize, CUdeviceptr dptr ): Get information on memory allocations.
CUresult cuMemGetInfo ( size_t* free, size_t* total ): Gets free and total memory.
CUresult cuMemHostAlloc ( void** pp, size_t bytesize, unsigned int Flags ): Allocates page-locked host memory.
CUresult cuMemHostGetDevicePointer ( CUdeviceptr* pdptr, void* p, unsigned int Flags ): Passes back device pointer of mapped pinned memory.
CUresult cuMemHostGetFlags ( unsigned int* pFlags, void* p ): Passes back flags that were used for a pinned allocation.
CUresult cuMemHostRegister ( void* p, size_t bytesize, unsigned int Flags ): Registers an existing host memory range for use by CUDA.
CUresult cuMemHostUnregister ( void* p ): Unregisters a memory range that was registered with cuMemHostRegister.
CUresult cuMemcpy ( CUdeviceptr dst, CUdeviceptr src, size_t ByteCount ): Copies memory.
CUresult cuMemcpy2D ( const CUDA_MEMCPY2D* pCopy ): Copies memory for 2D arrays.
CUresult cuMemcpy2DAsync ( const CUDA_MEMCPY2D* pCopy, CUstream hStream ): Copies memory for 2D arrays.
CUresult cuMemcpy2DUnaligned ( const CUDA_MEMCPY2D* pCopy ): Copies memory for 2D arrays.
CUresult cuMemcpy3D ( const CUDA_MEMCPY3D* pCopy ): Copies memory for 3D arrays.
CUresult cuMemcpy3DAsync ( const CUDA_MEMCPY3D* pCopy, CUstream hStream ): Copies memory for 3D arrays.
CUresult cuMemcpy3DPeer ( const CUDA_MEMCPY3D_PEER* pCopy ): Copies memory between contexts.
CUresult cuMemcpy3DPeerAsync ( const CUDA_MEMCPY3D_PEER* pCopy, CUstream hStream ): Copies memory between contexts asynchronously.
CUresult cuMemcpyAsync ( CUdeviceptr dst, CUdeviceptr src, size_t ByteCount, CUstream hStream ): Copies memory asynchronously.
CUresult cuMemcpyAtoA ( CUarray dstArray, size_t dstOffset, CUarray srcArray, size_t srcOffset, size_t ByteCount ): Copies memory from Array to Array.
CUresult cuMemcpyAtoD ( CUdeviceptr dstDevice, CUarray srcArray, size_t srcOffset, size_t ByteCount ): Copies memory from Array to Device.
CUresult cuMemcpyAtoH ( void* dstHost, CUarray srcArray, size_t srcOffset, size_t ByteCount ): Copies memory from Array to Host.
CUresult cuMemcpyAtoHAsync ( void* dstHost, CUarray srcArray, size_t srcOffset, size_t ByteCount, CUstream hStream ): Copies memory from Array to Host.
CUresult cuMemcpyDtoA ( CUarray dstArray, size_t dstOffset, CUdeviceptr srcDevice, size_t ByteCount ): Copies memory from Device to Array.
CUresult cuMemcpyDtoD ( CUdeviceptr dstDevice, CUdeviceptr srcDevice, size_t ByteCount ): Copies memory from Device to Device.
CUresult cuMemcpyDtoDAsync ( CUdeviceptr dstDevice, CUdeviceptr srcDevice, size_t ByteCount, CUstream hStream ): Copies memory from Device to Device.
CUresult cuMemcpyDtoH ( void* dstHost, CUdeviceptr srcDevice, size_t ByteCount ): Copies memory from Device to Host.
CUresult cuMemcpyDtoHAsync ( void* dstHost, CUdeviceptr srcDevice, size_t ByteCount, CUstream hStream ): Copies memory from Device to Host.
CUresult cuMemcpyHtoA ( CUarray dstArray, size_t dstOffset, const void* srcHost, size_t ByteCount ): Copies memory from Host to Array.
CUresult cuMemcpyHtoAAsync ( CUarray dstArray, size_t dstOffset, const void* srcHost, size_t ByteCount, CUstream hStream ): Copies memory from Host to Array.
CUresult cuMemcpyHtoD ( CUdeviceptr dstDevice, const void* srcHost, size_t ByteCount ): Copies memory from Host to Device.
CUresult cuMemcpyHtoDAsync ( CUdeviceptr dstDevice, const void* srcHost, size_t ByteCount, CUstream hStream ): Copies memory from Host to Device.
CUresult cuMemcpyPeer ( CUdeviceptr dstDevice, CUcontext dstContext, CUdeviceptr srcDevice, CUcontext srcContext, size_t ByteCount ): Copies device memory between two contexts.
CUresult cuMemcpyPeerAsync ( CUdeviceptr dstDevice, CUcontext dstContext, CUdeviceptr srcDevice, CUcontext srcContext, size_t ByteCount, CUstream hStream ): Copies device memory between two contexts asynchronously.
CUresult cuMemsetD16 ( CUdeviceptr dstDevice, unsigned short us, size_t N ): Initializes device memory.
CUresult cuMemsetD16Async ( CUdeviceptr dstDevice, unsigned short us, size_t N, CUstream hStream ): Sets device memory.
CUresult cuMemsetD2D16 ( CUdeviceptr dstDevice, size_t dstPitch, unsigned short us, size_t Width, size_t Height ): Initializes device memory.
CUresult cuMemsetD2D16Async ( CUdeviceptr dstDevice, size_t dstPitch, unsigned short us, size_t Width, size_t Height, CUstream hStream ): Sets device memory.
CUresult cuMemsetD2D32 ( CUdeviceptr dstDevice, size_t dstPitch, unsigned int ui, size_t Width, size_t Height ): Initializes device memory.
CUresult cuMemsetD2D32Async ( CUdeviceptr dstDevice, size_t dstPitch, unsigned int ui, size_t Width, size_t Height, CUstream hStream ): Sets device memory.
CUresult cuMemsetD2D8 ( CUdeviceptr dstDevice, size_t dstPitch, unsigned char uc, size_t Width, size_t Height ): Initializes device memory.
CUresult cuMemsetD2D8Async ( CUdeviceptr dstDevice, size_t dstPitch, unsigned char uc, size_t Width, size_t Height, CUstream hStream ): Sets device memory.
CUresult cuMemsetD32 ( CUdeviceptr dstDevice, unsigned int ui, size_t N ): Initializes device memory.
CUresult cuMemsetD32Async ( CUdeviceptr dstDevice, unsigned int ui, size_t N, CUstream hStream ): Sets device memory.
CUresult cuMemsetD8 ( CUdeviceptr dstDevice, unsigned char uc, size_t N ): Initializes device memory.
CUresult cuMemsetD8Async ( CUdeviceptr dstDevice, unsigned char uc, size_t N, CUstream hStream ): Sets device memory.
CUresult cuMipmappedArrayCreate ( CUmipmappedArray* pHandle, const CUDA_ARRAY3D_DESCRIPTOR* pMipmappedArrayDesc, unsigned int numMipmapLevels ): Creates a CUDA mipmapped array.
CUresult cuMipmappedArrayDestroy ( CUmipmappedArray hMipmappedArray ): Destroys a CUDA mipmapped array.
CUresult cuMipmappedArrayGetLevel ( CUarray* pLevelArray, CUmipmappedArray hMipmappedArray, unsigned int level ): Gets a mipmap level of a CUDA mipmapped array.

Functions

CUresult cuArray3DCreate ( CUarray* pHandle, const CUDA_ARRAY3D_DESCRIPTOR* pAllocateArray )

Creates a 3D CUDA array.

Parameters

pHandle: - Returned array
pAllocateArray: - 3D array descriptor

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY, CUDA_ERROR_UNKNOWN

Description

Creates a CUDA array according to the CUDA_ARRAY3D_DESCRIPTOR structure pAllocateArray and returns a handle to the new CUDA array in *pHandle. The CUDA_ARRAY3D_DESCRIPTOR is defined as:

‎    typedef struct {
              unsigned int Width;
              unsigned int Height;
              unsigned int Depth;
              CUarray_format Format;
              unsigned int NumChannels;
              unsigned int Flags;
          } CUDA_ARRAY3D_DESCRIPTOR;

where:

Width, Height, and Depth are the width, height, and depth of the CUDA array (in elements); the following types of CUDA arrays can be allocated:
- A 1D array is allocated if Height and Depth extents are both zero.
- A 2D array is allocated if only Depth extent is zero.
- A 3D array is allocated if all three extents are non-zero.
- A 1D layered CUDA array is allocated if only Height is zero and the CUDA_ARRAY3D_LAYERED flag is set. Each layer is a 1D array. The number of layers is determined by the depth extent.
- A 2D layered CUDA array is allocated if all three extents are non-zero and the CUDA_ARRAY3D_LAYERED flag is set. Each layer is a 2D array. The number of layers is determined by the depth extent.
- A cubemap CUDA array is allocated if all three extents are non-zero and the CUDA_ARRAY3D_CUBEMAP flag is set. Width must be equal to Height, and Depth must be six. A cubemap is a special type of 2D layered CUDA array, where the six layers represent the six faces of a cube. The order of the six layers in memory is the same as that listed in CUarray_cubemap_face.
- A cubemap layered CUDA array is allocated if all three extents are non-zero, and both, CUDA_ARRAY3D_CUBEMAP and CUDA_ARRAY3D_LAYERED flags are set. Width must be equal to Height, and Depth must be a multiple of six. A cubemap layered CUDA array is a special type of 2D layered CUDA array that consists of a collection of cubemaps. The first six layers represent the first cubemap, the next six layers form the second cubemap, and so on.

Format specifies the format of the elements; CUarray_format is defined as:

‎    typedef enum CUarray_format_enum {
              CU_AD_FORMAT_UNSIGNED_INT8 = 0x01,
              CU_AD_FORMAT_UNSIGNED_INT16 = 0x02,
              CU_AD_FORMAT_UNSIGNED_INT32 = 0x03,
              CU_AD_FORMAT_SIGNED_INT8 = 0x08,
              CU_AD_FORMAT_SIGNED_INT16 = 0x09,
              CU_AD_FORMAT_SIGNED_INT32 = 0x0a,
              CU_AD_FORMAT_HALF = 0x10,
              CU_AD_FORMAT_FLOAT = 0x20
          } CUarray_format;

NumChannels specifies the number of packed components per CUDA array element; it may be 1, 2, or 4;

Flags may be set to
- CUDA_ARRAY3D_LAYERED to enable creation of layered CUDA arrays. If this flag is set, Depth specifies the number of layers, not the depth of a 3D array.
- CUDA_ARRAY3D_SURFACE_LDST to enable surface references to be bound to the CUDA array. If this flag is not set, cuSurfRefSetArray will fail when attempting to bind the CUDA array to a surface reference.
- CUDA_ARRAY3D_CUBEMAP to enable creation of cubemaps. If this flag is set, Width must be equal to Height, and Depth must be six. If the CUDA_ARRAY3D_LAYERED flag is also set, then Depth must be a multiple of six.
- CUDA_ARRAY3D_TEXTURE_GATHER to indicate that the CUDA array will be used for texture gather. Texture gather can only be performed on 2D CUDA arrays.

Width, Height and Depth must meet certain size requirements as listed in the following table. All values are specified in elements. Note that for brevity's sake, the full name of the device attribute is not specified. For ex., TEXTURE1D_WIDTH refers to the device attribute CU_DEVICE_ATTRIBUTE_MAXIMUM_TEXTURE1D_WIDTH.

Note that 2D CUDA arrays have different size requirements if the CUDA_ARRAY3D_TEXTURE_GATHER flag is set. Width and Height must not be greater than CU_DEVICE_ATTRIBUTE_MAXIMUM_TEXTURE2D_GATHER_WIDTH and CU_DEVICE_ATTRIBUTE_MAXIMUM_TEXTURE2D_GATHER_HEIGHT respectively, in that case.

CUDA array type	Valid extents that must always be met {(width range in elements), (height range), (depth range)}	Valid extents with CUDA_ARRAY3D_SURFACE_LDST set {(width range in elements), (height range), (depth range)}
1D	{ (1,TEXTURE1D_WIDTH), 0, 0 }	{ (1,SURFACE1D_WIDTH), 0, 0 }
2D	{ (1,TEXTURE2D_WIDTH), (1,TEXTURE2D_HEIGHT), 0 }	{ (1,SURFACE2D_WIDTH), (1,SURFACE2D_HEIGHT), 0 }
3D	{ (1,TEXTURE3D_WIDTH), (1,TEXTURE3D_HEIGHT), (1,TEXTURE3D_DEPTH) } OR { (1,TEXTURE3D_WIDTH_ALTERNATE), (1,TEXTURE3D_HEIGHT_ALTERNATE), (1,TEXTURE3D_DEPTH_ALTERNATE) }	{ (1,SURFACE3D_WIDTH), (1,SURFACE3D_HEIGHT), (1,SURFACE3D_DEPTH) }
1D Layered	{ (1,TEXTURE1D_LAYERED_WIDTH), 0, (1,TEXTURE1D_LAYERED_LAYERS) }	{ (1,SURFACE1D_LAYERED_WIDTH), 0, (1,SURFACE1D_LAYERED_LAYERS) }
2D Layered	{ (1,TEXTURE2D_LAYERED_WIDTH), (1,TEXTURE2D_LAYERED_HEIGHT), (1,TEXTURE2D_LAYERED_LAYERS) }	{ (1,SURFACE2D_LAYERED_WIDTH), (1,SURFACE2D_LAYERED_HEIGHT), (1,SURFACE2D_LAYERED_LAYERS) }
Cubemap	{ (1,TEXTURECUBEMAP_WIDTH), (1,TEXTURECUBEMAP_WIDTH), 6 }	{ (1,SURFACECUBEMAP_WIDTH), (1,SURFACECUBEMAP_WIDTH), 6 }
Cubemap Layered	{ (1,TEXTURECUBEMAP_LAYERED_WIDTH), (1,TEXTURECUBEMAP_LAYERED_WIDTH), (1,TEXTURECUBEMAP_LAYERED_LAYERS) }	{ (1,SURFACECUBEMAP_LAYERED_WIDTH), (1,SURFACECUBEMAP_LAYERED_WIDTH), (1,SURFACECUBEMAP_LAYERED_LAYERS) }

Here are examples of CUDA array descriptions:

Description for a CUDA array of 2048 floats:

‎    CUDA_ARRAY3D_DESCRIPTOR desc;
          desc.Format = CU_AD_FORMAT_FLOAT;
          desc.NumChannels = 1;
          desc.Width = 2048;
          desc.Height = 0;
          desc.Depth = 0;

Description for a 64 x 64 CUDA array of floats:

‎    CUDA_ARRAY3D_DESCRIPTOR desc;
          desc.Format = CU_AD_FORMAT_FLOAT;
          desc.NumChannels = 1;
          desc.Width = 64;
          desc.Height = 64;
          desc.Depth = 0;

Description for a width x height x depth CUDA array of 64-bit, 4x16-bit float16's:

‎    CUDA_ARRAY3D_DESCRIPTOR desc;
          desc.FormatFlags = CU_AD_FORMAT_HALF;
          desc.NumChannels = 4;
          desc.Width = width;
          desc.Height = height;
          desc.Depth = depth;

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuArray3DGetDescriptor ( CUDA_ARRAY3D_DESCRIPTOR* pArrayDescriptor, CUarray hArray )

Get a 3D CUDA array descriptor.

Parameters

pArrayDescriptor: - Returned 3D array descriptor
hArray: - 3D array to get descriptor of

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_INVALID_HANDLE

Description

Returns in *pArrayDescriptor a descriptor containing information on the format and dimensions of the CUDA array hArray. It is useful for subroutines that have been passed a CUDA array, but need to know the CUDA array parameters for validation or other purposes.

This function may be called on 1D and 2D arrays, in which case the Height and/or Depth members of the descriptor struct will be set to 0.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuArrayCreate ( CUarray* pHandle, const CUDA_ARRAY_DESCRIPTOR* pAllocateArray )

Creates a 1D or 2D CUDA array.

Parameters

pHandle: - Returned array
pAllocateArray: - Array descriptor

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY, CUDA_ERROR_UNKNOWN

Description

Creates a CUDA array according to the CUDA_ARRAY_DESCRIPTOR structure pAllocateArray and returns a handle to the new CUDA array in *pHandle. The CUDA_ARRAY_DESCRIPTOR is defined as:

‎    typedef struct {
              unsigned int Width;
              unsigned int Height;
              CUarray_format Format;
              unsigned int NumChannels;
          } CUDA_ARRAY_DESCRIPTOR;

where:

Width, and Height are the width, and height of the CUDA array (in elements); the CUDA array is one-dimensional if height is 0, two-dimensional otherwise;

Format specifies the format of the elements; CUarray_format is defined as:

‎    typedef enum CUarray_format_enum {
              CU_AD_FORMAT_UNSIGNED_INT8 = 0x01,
              CU_AD_FORMAT_UNSIGNED_INT16 = 0x02,
              CU_AD_FORMAT_UNSIGNED_INT32 = 0x03,
              CU_AD_FORMAT_SIGNED_INT8 = 0x08,
              CU_AD_FORMAT_SIGNED_INT16 = 0x09,
              CU_AD_FORMAT_SIGNED_INT32 = 0x0a,
              CU_AD_FORMAT_HALF = 0x10,
              CU_AD_FORMAT_FLOAT = 0x20
          } CUarray_format;

NumChannels specifies the number of packed components per CUDA array element; it may be 1, 2, or 4;

Here are examples of CUDA array descriptions:

Description for a CUDA array of 2048 floats:

‎    CUDA_ARRAY_DESCRIPTOR desc;
          desc.Format = CU_AD_FORMAT_FLOAT;
          desc.NumChannels = 1;
          desc.Width = 2048;
          desc.Height = 1;

Description for a 64 x 64 CUDA array of floats:

‎    CUDA_ARRAY_DESCRIPTOR desc;
          desc.Format = CU_AD_FORMAT_FLOAT;
          desc.NumChannels = 1;
          desc.Width = 64;
          desc.Height = 64;

Description for a width x height CUDA array of 64-bit, 4x16-bit float16's:

‎    CUDA_ARRAY_DESCRIPTOR desc;
          desc.FormatFlags = CU_AD_FORMAT_HALF;
          desc.NumChannels = 4;
          desc.Width = width;
          desc.Height = height;

Description for a width x height CUDA array of 16-bit elements, each of which is two 8-bit unsigned chars:

‎    CUDA_ARRAY_DESCRIPTOR arrayDesc;
          desc.FormatFlags = CU_AD_FORMAT_UNSIGNED_INT8;
          desc.NumChannels = 2;
          desc.Width = width;
          desc.Height = height;

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuArrayDestroy ( CUarray hArray )

Destroys a CUDA array.

Parameters

hArray: - Array to destroy

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_HANDLE, CUDA_ERROR_ARRAY_IS_MAPPED

Description

Destroys the CUDA array hArray.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuArrayGetDescriptor ( CUDA_ARRAY_DESCRIPTOR* pArrayDescriptor, CUarray hArray )

Get a 1D or 2D CUDA array descriptor.

Parameters

pArrayDescriptor: - Returned array descriptor
hArray: - Array to get descriptor of

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_INVALID_HANDLE

Description

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuDeviceGetByPCIBusId ( CUdevice* dev, const char* pciBusId )

Returns a handle to a compute device.

Parameters

dev: - Returned device handle
pciBusId: - String in one of the following forms: [domain]:[bus]:[device].[function] [domain]:[bus]:[device] [bus]:[device].[function] where domain, bus, device, and function are all hexadecimal values

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_INVALID_DEVICE

Description

Returns in *device a device handle given a PCI bus ID string.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuDeviceGetPCIBusId ( char* pciBusId, int len, CUdevice dev )

Returns a PCI Bus Id string for the device.

Parameters

pciBusId: - Returned identifier string for the device in the following format [domain]:[bus]:[device].[function] where domain, bus, device, and function are all hexadecimal values. pciBusId should be large enough to store 13 characters including the NULL-terminator.
len: - Maximum length of string to store in name
dev: - Device to get identifier string for

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_INVALID_DEVICE

Description

Returns an ASCII string identifying the device dev in the NULL-terminated string pointed to by pciBusId. len specifies the maximum length of the string that may be returned.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuIpcCloseMemHandle ( CUdeviceptr dptr )

Close memory mapped with cuIpcOpenMemHandle.

Parameters

dptr: - Device pointer returned by cuIpcOpenMemHandle

Returns

CUDA_SUCCESS, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_MAP_FAILED, CUDA_ERROR_INVALID_HANDLE,

Description

Unmaps memory returnd by cuIpcOpenMemHandle. The original allocation in the exporting process as well as imported mappings in other processes will be unaffected.

Any resources used to enable peer access will be freed if this is the last mapping using them.

IPC functionality is restricted to devices with support for unified addressing on Linux operating systems.

CUresult cuIpcGetEventHandle ( CUipcEventHandle* pHandle, CUevent event )

Gets an interprocess handle for a previously allocated event.

Parameters

pHandle: - Pointer to a user allocated CUipcEventHandle in which to return the opaque event handle
event: - Event allocated with CU_EVENT_INTERPROCESS and CU_EVENT_DISABLE_TIMING flags.

Returns

CUDA_SUCCESS, CUDA_ERROR_INVALID_HANDLE, CUDA_ERROR_OUT_OF_MEMORY, CUDA_ERROR_MAP_FAILED

Description

Takes as input a previously allocated event. This event must have been created with the CU_EVENT_INTERPROCESS and CU_EVENT_DISABLE_TIMING flags set. This opaque handle may be copied into other processes and opened with cuIpcOpenEventHandle to allow efficient hardware synchronization between GPU work in different processes.

After the event has been opened in the importing process, cuEventRecord, cuEventSynchronize, cuStreamWaitEvent and cuEventQuery may be used in either process. Performing operations on the imported event after the exported event has been freed with cuEventDestroy will result in undefined behavior.

IPC functionality is restricted to devices with support for unified addressing on Linux operating systems.

CUresult cuIpcGetMemHandle ( CUipcMemHandle* pHandle, CUdeviceptr dptr )

Gets an interprocess memory handle for an existing device memory allocation.

Parameters

pHandle: - Pointer to user allocated CUipcMemHandle to return the handle in.
dptr: - Base pointer to previously allocated device memory

Returns

CUDA_SUCCESS, CUDA_ERROR_INVALID_HANDLE, CUDA_ERROR_OUT_OF_MEMORY, CUDA_ERROR_MAP_FAILED,

Description

Takes a pointer to the base of an existing device memory allocation created with cuMemAlloc and exports it for use in another process. This is a lightweight operation and may be called multiple times on an allocation without adverse effects.

If a region of memory is freed with cuMemFree and a subsequent call to cuMemAlloc returns memory with the same device address, cuIpcGetMemHandle will return a unique handle for the new memory.

IPC functionality is restricted to devices with support for unified addressing on Linux operating systems.

CUresult cuIpcOpenEventHandle ( CUevent* phEvent, CUipcEventHandle handle )

Opens an interprocess event handle for use in the current process.

Parameters

phEvent: - Returns the imported event
handle: - Interprocess handle to open

Returns

CUDA_SUCCESS, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_MAP_FAILED, CUDA_ERROR_PEER_ACCESS_UNSUPPORTED, CUDA_ERROR_INVALID_HANDLE

Description

Opens an interprocess event handle exported from another process with cuIpcGetEventHandle. This function returns a CUevent that behaves like a locally created event with the CU_EVENT_DISABLE_TIMING flag specified. This event must be freed with cuEventDestroy.

Performing operations on the imported event after the exported event has been freed with cuEventDestroy will result in undefined behavior.

IPC functionality is restricted to devices with support for unified addressing on Linux operating systems.

CUresult cuIpcOpenMemHandle ( CUdeviceptr* pdptr, CUipcMemHandle handle, unsigned int Flags )

Opens an interprocess memory handle exported from another process and returns a device pointer usable in the local process.

Parameters

pdptr: - Returned device pointer
handle: - CUipcMemHandle to open
Flags: - Flags for this operation. Must be specified as CU_IPC_MEM_LAZY_ENABLE_PEER_ACCESS

Returns

CUDA_SUCCESS, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_MAP_FAILED, CUDA_ERROR_INVALID_HANDLE, CUDA_ERROR_TOO_MANY_PEERS

Description

Maps memory exported from another process with cuIpcGetMemHandle into the current device address space. For contexts on different devices cuIpcOpenMemHandle can attempt to enable peer access between the devices as if the user called cuCtxEnablePeerAccess. This behavior is controlled by the CU_IPC_MEM_LAZY_ENABLE_PEER_ACCESS flag. cuDeviceCanAccessPeer can determine if a mapping is possible.

Contexts that may open CUipcMemHandles are restricted in the following way. CUipcMemHandles from each CUdevice in a given process may only be opened by one CUcontext per CUdevice per other process.

Memory returned from cuIpcOpenMemHandle must be freed with cuIpcCloseMemHandle.

Calling cuMemFree on an exported memory region before calling cuIpcCloseMemHandle in the importing context will result in undefined behavior.

IPC functionality is restricted to devices with support for unified addressing on Linux operating systems.

Note:

No guarantees are made about the address returned in *pdptr. In particular, multiple processes may not receive the same address for the same handle.

CUresult cuMemAlloc ( CUdeviceptr* dptr, size_t bytesize )

Allocates device memory.

Parameters

dptr: - Returned device pointer
bytesize: - Requested allocation size in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY

Description

Allocates bytesize bytes of linear memory on the device and returns in *dptr a pointer to the allocated memory. The allocated memory is suitably aligned for any kind of variable. The memory is not cleared. If bytesize is 0, cuMemAlloc() returns CUDA_ERROR_INVALID_VALUE.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemAllocHost ( void** pp, size_t bytesize )

Allocates page-locked host memory.

Parameters

pp: - Returned host pointer to page-locked memory
bytesize: - Requested allocation size in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY

Description

Allocates bytesize bytes of host memory that is page-locked and accessible to the device. The driver tracks the virtual memory ranges allocated with this function and automatically accelerates calls to functions such as cuMemcpy(). Since the memory can be accessed directly by the device, it can be read or written with much higher bandwidth than pageable memory obtained with functions such as malloc(). Allocating excessive amounts of memory with cuMemAllocHost() may degrade system performance, since it reduces the amount of memory available to the system for paging. As a result, this function is best used sparingly to allocate staging areas for data exchange between host and device.

Note all host memory allocated using cuMemHostAlloc() will automatically be immediately accessible to all contexts on all devices which support unified addressing (as may be queried using CU_DEVICE_ATTRIBUTE_UNIFIED_ADDRESSING). The device pointer that may be used to access this host memory from those contexts is always equal to the returned host pointer *pp. See Unified Addressing for additional details.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemAllocManaged ( CUdeviceptr* dptr, size_t bytesize, unsigned int flags )

Allocates memory that will be automatically managed by the Unified Memory system.

Parameters

dptr: - Returned device pointer
bytesize: - Requested allocation size in bytes
flags: - Must be one of CU_MEM_ATTACH_GLOBAL or CU_MEM_ATTACH_HOST

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_NOT_SUPPORTED, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY

Description

Allocates bytesize bytes of managed memory on the device and returns in *dptr a pointer to the allocated memory. If the device doesn't support allocating managed memory, CUDA_ERROR_NOT_SUPPORTED is returned. Support for managed memory can be queried using the device attribute CU_DEVICE_ATTRIBUTE_MANAGED_MEMORY. The allocated memory is suitably aligned for any kind of variable. The memory is not cleared. If bytesize is 0, cuMemAllocManaged returns CUDA_ERROR_INVALID_VALUE. The pointer is valid on the CPU and on all GPUs in the system that support managed memory. All accesses to this pointer must obey the Unified Memory programming model.

flags specifies the default stream association for this allocation. flags must be one of CU_MEM_ATTACH_GLOBAL or CU_MEM_ATTACH_HOST. If CU_MEM_ATTACH_GLOBAL is specified, then this memory is accessible from any stream on any device. If CU_MEM_ATTACH_HOST is specified, then the allocation should not be accessed from devices that have a zero value for the device attribute CU_DEVICE_ATTRIBUTE_CONCURRENT_MANAGED_ACCESS; an explicit call to cuStreamAttachMemAsync will be required to enable access on such devices.

If the association is later changed via cuStreamAttachMemAsync to a single stream, the default association as specifed during cuMemAllocManaged is restored when that stream is destroyed. For __managed__ variables, the default association is always CU_MEM_ATTACH_GLOBAL. Note that destroying a stream is an asynchronous operation, and as a result, the change to default association won't happen until all work in the stream has completed.

Memory allocated with cuMemAllocManaged should be released with cuMemFree.

Device memory oversubscription is possible for GPUs that have a non-zero value for the device attribute CU_DEVICE_ATTRIBUTE_CONCURRENT_MANAGED_ACCESS. Managed memory on such GPUs may be evicted from device memory to host memory at any time by the Unified Memory driver in order to make room for other allocations.

In a multi-GPU system where all GPUs have a non-zero value for the device attribute CU_DEVICE_ATTRIBUTE_CONCURRENT_MANAGED_ACCESS, managed memory may not be populated when this API returns and instead may be populated on access. In such systems, managed memory can migrate to any processor's memory at any time. The Unified Memory driver will employ heuristics to maintain data locality and prevent excessive page faults to the extent possible. The application can also guide the driver about memory usage patterns via cuMemAdvise. The application can also explicitly migrate memory to a desired processor's memory via cuMemPrefetchAsync.

In a multi-GPU system where all of the GPUs have a zero value for the device attribute CU_DEVICE_ATTRIBUTE_CONCURRENT_MANAGED_ACCESS and all the GPUs have peer-to-peer support with each other, the physical storage for managed memory is created on the GPU which is active at the time cuMemAllocManaged is called. All other GPUs will reference the data at reduced bandwidth via peer mappings over the PCIe bus. The Unified Memory driver does not migrate memory among such GPUs.

In a multi-GPU system where not all GPUs have peer-to-peer support with each other and where the value of the device attribute CU_DEVICE_ATTRIBUTE_CONCURRENT_MANAGED_ACCESS is zero for at least one of those GPUs, the location chosen for physical storage of managed memory is system-dependent.

On Linux, the location chosen will be device memory as long as the current set of active contexts are on devices that either have peer-to-peer support with each other or have a non-zero value for the device attribute CU_DEVICE_ATTRIBUTE_CONCURRENT_MANAGED_ACCESS. If there is an active context on a GPU that does not have a non-zero value for that device attribute and it does not have peer-to-peer support with the other devices that have active contexts on them, then the location for physical storage will be 'zero-copy' or host memory. Note that this means that managed memory that is located in device memory is migrated to host memory if a new context is created on a GPU that doesn't have a non-zero value for the device attribute and does not support peer-to-peer with at least one of the other devices that has an active context. This in turn implies that context creation may fail if there is insufficient host memory to migrate all managed allocations.
On Windows, the physical storage is always created in 'zero-copy' or host memory. All GPUs will reference the data at reduced bandwidth over the PCIe bus. In these circumstances, use of the environment variable CUDA_VISIBLE_DEVICES is recommended to restrict CUDA to only use those GPUs that have peer-to-peer support. Alternatively, users can also set CUDA_MANAGED_FORCE_DEVICE_ALLOC to a non-zero value to force the driver to always use device memory for physical storage. When this environment variable is set to a non-zero value, all contexts created in that process on devices that support managed memory have to be peer-to-peer compatible with each other. Context creation will fail if a context is created on a device that supports managed memory and is not peer-to-peer compatible with any of the other managed memory supporting devices on which contexts were previously created, even if those contexts have been destroyed. These environment variables are described in the CUDA programming guide under the "CUDA environment variables" section.
On ARM, managed memory is not available on discrete gpu with Drive PX-2.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

See also:

CUresult cuMemAllocPitch ( CUdeviceptr* dptr, size_t* pPitch, size_t WidthInBytes, size_t Height, unsigned int ElementSizeBytes )

Allocates pitched device memory.

Parameters

dptr: - Returned device pointer
pPitch: - Returned pitch of allocation in bytes
WidthInBytes: - Requested allocation width in bytes
Height: - Requested allocation height in rows
ElementSizeBytes: - Size of largest reads/writes for range

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY

Description

Allocates at least WidthInBytes * Height bytes of linear memory on the device and returns in *dptr a pointer to the allocated memory. The function may pad the allocation to ensure that corresponding pointers in any given row will continue to meet the alignment requirements for coalescing as the address is updated from row to row. ElementSizeBytes specifies the size of the largest reads and writes that will be performed on the memory range. ElementSizeBytes may be 4, 8 or 16 (since coalesced memory transactions are not possible on other data sizes). If ElementSizeBytes is smaller than the actual read/write size of a kernel, the kernel will run correctly, but possibly at reduced speed. The pitch returned in *pPitch by cuMemAllocPitch() is the width in bytes of the allocation. The intended usage of pitch is as a separate parameter of the allocation, used to compute addresses within the 2D array. Given the row and column of an array element of type T, the address is computed as:

‎   T* pElement = (T*)((char*)BaseAddress + Row * Pitch) + Column;

The pitch returned by cuMemAllocPitch() is guaranteed to work with cuMemcpy2D() under all circumstances. For allocations of 2D arrays, it is recommended that programmers consider performing pitch allocations using cuMemAllocPitch(). Due to alignment restrictions in the hardware, this is especially true if the application will be performing 2D memory copies between different regions of device memory (whether linear memory or CUDA arrays).

The byte alignment of the pitch returned by cuMemAllocPitch() is guaranteed to match or exceed the alignment requirement for texture binding with cuTexRefSetAddress2D().

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemFree ( CUdeviceptr dptr )

Frees device memory.

Parameters

dptr: - Pointer to memory to free

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Frees the memory space pointed to by dptr, which must have been returned by a previous call to cuMemAlloc() or cuMemAllocPitch().

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemFreeHost ( void* p )

Frees page-locked host memory.

Parameters

p: - Pointer to memory to free

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Frees the memory space pointed to by p, which must have been returned by a previous call to cuMemAllocHost().

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemGetAddressRange ( CUdeviceptr* pbase, size_t* psize, CUdeviceptr dptr )

Get information on memory allocations.

Parameters

pbase: - Returned base address
psize: - Returned size of device memory allocation
dptr: - Device pointer to query

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_NOT_FOUND, CUDA_ERROR_INVALID_VALUE

Description

Returns the base address in *pbase and size in *psize of the allocation by cuMemAlloc() or cuMemAllocPitch() that contains the input pointer dptr. Both parameters pbase and psize are optional. If one of them is NULL, it is ignored.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemGetInfo ( size_t* free, size_t* total )

Gets free and total memory.

Parameters

free: - Returned free memory in bytes
total: - Returned total memory in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Returns in *free and *total respectively, the free and total amount of memory available for allocation by the CUDA context, in bytes.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemHostAlloc ( void** pp, size_t bytesize, unsigned int Flags )

Allocates page-locked host memory.

Parameters

pp: - Returned host pointer to page-locked memory
bytesize: - Requested allocation size in bytes
Flags: - Flags for allocation request

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY

Description

Allocates bytesize bytes of host memory that is page-locked and accessible to the device. The driver tracks the virtual memory ranges allocated with this function and automatically accelerates calls to functions such as cuMemcpyHtoD(). Since the memory can be accessed directly by the device, it can be read or written with much higher bandwidth than pageable memory obtained with functions such as malloc(). Allocating excessive amounts of pinned memory may degrade system performance, since it reduces the amount of memory available to the system for paging. As a result, this function is best used sparingly to allocate staging areas for data exchange between host and device.

The Flags parameter enables different options to be specified that affect the allocation, as follows.

CU_MEMHOSTALLOC_PORTABLE: The memory returned by this call will be considered as pinned memory by all CUDA contexts, not just the one that performed the allocation.

CU_MEMHOSTALLOC_DEVICEMAP: Maps the allocation into the CUDA address space. The device pointer to the memory may be obtained by calling cuMemHostGetDevicePointer().

CU_MEMHOSTALLOC_WRITECOMBINED: Allocates the memory as write-combined (WC). WC memory can be transferred across the PCI Express bus more quickly on some system configurations, but cannot be read efficiently by most CPUs. WC memory is a good option for buffers that will be written by the CPU and read by the GPU via mapped pinned memory or host->device transfers.

All of these flags are orthogonal to one another: a developer may allocate memory that is portable, mapped and/or write-combined with no restrictions.

The CUDA context must have been created with the CU_CTX_MAP_HOST flag in order for the CU_MEMHOSTALLOC_DEVICEMAP flag to have any effect.

The CU_MEMHOSTALLOC_DEVICEMAP flag may be specified on CUDA contexts for devices that do not support mapped pinned memory. The failure is deferred to cuMemHostGetDevicePointer() because the memory may be mapped into other CUDA contexts via the CU_MEMHOSTALLOC_PORTABLE flag.

The memory allocated by this function must be freed with cuMemFreeHost().

Note all host memory allocated using cuMemHostAlloc() will automatically be immediately accessible to all contexts on all devices which support unified addressing (as may be queried using CU_DEVICE_ATTRIBUTE_UNIFIED_ADDRESSING). Unless the flag CU_MEMHOSTALLOC_WRITECOMBINED is specified, the device pointer that may be used to access this host memory from those contexts is always equal to the returned host pointer *pp. If the flag CU_MEMHOSTALLOC_WRITECOMBINED is specified, then the function cuMemHostGetDevicePointer() must be used to query the device pointer, even if the context supports unified addressing. See Unified Addressing for additional details.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemHostGetDevicePointer ( CUdeviceptr* pdptr, void* p, unsigned int Flags )

Passes back device pointer of mapped pinned memory.

Parameters

pdptr: - Returned device pointer
p: - Host pointer
Flags: - Options (must be 0)

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Passes back the device pointer pdptr corresponding to the mapped, pinned host buffer p allocated by cuMemHostAlloc.

cuMemHostGetDevicePointer() will fail if the CU_MEMHOSTALLOC_DEVICEMAP flag was not specified at the time the memory was allocated, or if the function is called on a GPU that does not support mapped pinned memory.

For devices that have a non-zero value for the device attribute CU_DEVICE_ATTRIBUTE_CAN_USE_HOST_POINTER_FOR_REGISTERED_MEM, the memory can also be accessed from the device using the host pointer p. The device pointer returned by cuMemHostGetDevicePointer() may or may not match the original host pointer p and depends on the devices visible to the application. If all devices visible to the application have a non-zero value for the device attribute, the device pointer returned by cuMemHostGetDevicePointer() will match the original pointer p. If any device visible to the application has a zero value for the device attribute, the device pointer returned by cuMemHostGetDevicePointer() will not match the original host pointer p, but it will be suitable for use on all devices provided Unified Virtual Addressing is enabled. In such systems, it is valid to access the memory using either pointer on devices that have a non-zero value for the device attribute. Note however that such devices should access the memory using only of the two pointers and not both.

Flags provides for future releases. For now, it must be set to 0.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemHostGetFlags ( unsigned int* pFlags, void* p )

Passes back flags that were used for a pinned allocation.

Parameters

pFlags: - Returned flags word
p: - Host pointer

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Passes back the flags pFlags that were specified when allocating the pinned host buffer p allocated by cuMemHostAlloc.

cuMemHostGetFlags() will fail if the pointer does not reside in an allocation performed by cuMemAllocHost() or cuMemHostAlloc().

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemHostRegister ( void* p, size_t bytesize, unsigned int Flags )

Registers an existing host memory range for use by CUDA.

Parameters

p: - Host pointer to memory to page-lock
bytesize: - Size in bytes of the address range to page-lock
Flags: - Flags for allocation request

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY, CUDA_ERROR_HOST_MEMORY_ALREADY_REGISTERED, CUDA_ERROR_NOT_PERMITTED, CUDA_ERROR_NOT_SUPPORTED

Description

Page-locks the memory range specified by p and bytesize and maps it for the device(s) as specified by Flags. This memory range also is added to the same tracking mechanism as cuMemHostAlloc to automatically accelerate calls to functions such as cuMemcpyHtoD(). Since the memory can be accessed directly by the device, it can be read or written with much higher bandwidth than pageable memory that has not been registered. Page-locking excessive amounts of memory may degrade system performance, since it reduces the amount of memory available to the system for paging. As a result, this function is best used sparingly to register staging areas for data exchange between host and device.

This function has limited support on Mac OS X. OS 10.7 or higher is required.

The Flags parameter enables different options to be specified that affect the allocation, as follows.

CU_MEMHOSTREGISTER_PORTABLE: The memory returned by this call will be considered as pinned memory by all CUDA contexts, not just the one that performed the allocation.

CU_MEMHOSTREGISTER_DEVICEMAP: Maps the allocation into the CUDA address space. The device pointer to the memory may be obtained by calling cuMemHostGetDevicePointer().

CU_MEMHOSTREGISTER_IOMEMORY: The pointer is treated as pointing to some I/O memory space, e.g. the PCI Express resource of a 3rd party device.

All of these flags are orthogonal to one another: a developer may page-lock memory that is portable or mapped with no restrictions.

The CUDA context must have been created with the CU_CTX_MAP_HOST flag in order for the CU_MEMHOSTREGISTER_DEVICEMAP flag to have any effect.

The CU_MEMHOSTREGISTER_DEVICEMAP flag may be specified on CUDA contexts for devices that do not support mapped pinned memory. The failure is deferred to cuMemHostGetDevicePointer() because the memory may be mapped into other CUDA contexts via the CU_MEMHOSTREGISTER_PORTABLE flag.

For devices that have a non-zero value for the device attribute CU_DEVICE_ATTRIBUTE_CAN_USE_HOST_POINTER_FOR_REGISTERED_MEM, the memory can also be accessed from the device using the host pointer p. The device pointer returned by cuMemHostGetDevicePointer() may or may not match the original host pointer ptr and depends on the devices visible to the application. If all devices visible to the application have a non-zero value for the device attribute, the device pointer returned by cuMemHostGetDevicePointer() will match the original pointer ptr. If any device visible to the application has a zero value for the device attribute, the device pointer returned by cuMemHostGetDevicePointer() will not match the original host pointer ptr, but it will be suitable for use on all devices provided Unified Virtual Addressing is enabled. In such systems, it is valid to access the memory using either pointer on devices that have a non-zero value for the device attribute. Note however that such devices should access the memory using only of the two pointers and not both.

The memory page-locked by this function must be unregistered with cuMemHostUnregister().

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMemHostUnregister ( void* p )

Unregisters a memory range that was registered with cuMemHostRegister.

Parameters

p: - Host pointer to memory to unregister

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY, CUDA_ERROR_HOST_MEMORY_NOT_REGISTERED,

Description

Unmaps the memory range whose base address is specified by p, and makes it pageable again.

The base address must be the same one specified to cuMemHostRegister().

Note:

Note that this function may also return error codes from previous, asynchronous launches.

See also:

cuMemHostRegister, cudaHostUnregister

CUresult cuMemcpy ( CUdeviceptr dst, CUdeviceptr src, size_t ByteCount )

Copies memory.

Parameters

dst: - Destination unified virtual address space pointer
src: - Source unified virtual address space pointer
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies data between two pointers. dst and src are base pointers of the destination and source, respectively. ByteCount specifies the number of bytes to copy. Note that this function infers the type of the transfer (host to host, host to device, device to device, or device to host) from the pointer values. This function is only allowed in contexts which support unified addressing.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpy2D ( const CUDA_MEMCPY2D* pCopy )

Copies memory for 2D arrays.

Parameters

pCopy: - Parameters for the memory copy

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Perform a 2D memory copy according to the parameters specified in pCopy. The CUDA_MEMCPY2D structure is defined as:

‎   typedef struct CUDA_MEMCPY2D_st {
            unsigned int srcXInBytes, srcY;
            CUmemorytype srcMemoryType;
                const void *srcHost;
                CUdeviceptr srcDevice;
                CUarray srcArray;
                unsigned int srcPitch;
      
            unsigned int dstXInBytes, dstY;
            CUmemorytype dstMemoryType;
                void *dstHost;
                CUdeviceptr dstDevice;
                CUarray dstArray;
                unsigned int dstPitch;
      
            unsigned int WidthInBytes;
            unsigned int Height;
         } CUDA_MEMCPY2D;

where:

srcMemoryType and dstMemoryType specify the type of memory of the source and destination, respectively; CUmemorytype_enum is defined as:

‎   typedef enum CUmemorytype_enum {
            CU_MEMORYTYPE_HOST = 0x01,
            CU_MEMORYTYPE_DEVICE = 0x02,
            CU_MEMORYTYPE_ARRAY = 0x03,
            CU_MEMORYTYPE_UNIFIED = 0x04
         } CUmemorytype;

If srcMemoryType is CU_MEMORYTYPE_UNIFIED, srcDevice and srcPitch specify the (unified virtual address space) base address of the source data and the bytes per row to apply. srcArray is ignored. This value may be used only if unified addressing is supported in the calling context.

If srcMemoryType is CU_MEMORYTYPE_HOST, srcHost and srcPitch specify the (host) base address of the source data and the bytes per row to apply. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_DEVICE, srcDevice and srcPitch specify the (device) base address of the source data and the bytes per row to apply. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_ARRAY, srcArray specifies the handle of the source data. srcHost, srcDevice and srcPitch are ignored.

If dstMemoryType is CU_MEMORYTYPE_HOST, dstHost and dstPitch specify the (host) base address of the destination data and the bytes per row to apply. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_UNIFIED, dstDevice and dstPitch specify the (unified virtual address space) base address of the source data and the bytes per row to apply. dstArray is ignored. This value may be used only if unified addressing is supported in the calling context.

If dstMemoryType is CU_MEMORYTYPE_DEVICE, dstDevice and dstPitch specify the (device) base address of the destination data and the bytes per row to apply. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_ARRAY, dstArray specifies the handle of the destination data. dstHost, dstDevice and dstPitch are ignored.

srcXInBytes and srcY specify the base address of the source data for the copy.

For host pointers, the starting address is

‎  void* Start = (void*)((char*)srcHost+srcY*srcPitch + srcXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr Start = srcDevice+srcY*srcPitch+srcXInBytes;

For CUDA arrays, srcXInBytes must be evenly divisible by the array element size.

dstXInBytes and dstY specify the base address of the destination data for the copy.

For host pointers, the base address is

‎  void* dstStart = (void*)((char*)dstHost+dstY*dstPitch + dstXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr dstStart = dstDevice+dstY*dstPitch+dstXInBytes;

For CUDA arrays, dstXInBytes must be evenly divisible by the array element size.

WidthInBytes and Height specify the width (in bytes) and height of the 2D copy being performed.
If specified, srcPitch must be greater than or equal to WidthInBytes + srcXInBytes, and dstPitch must be greater than or equal to WidthInBytes + dstXInBytes.

cuMemcpy2D() returns an error if any pitch is greater than the maximum allowed (CU_DEVICE_ATTRIBUTE_MAX_PITCH). cuMemAllocPitch() passes back pitches that always work with cuMemcpy2D(). On intra-device memory copies (device to device, CUDA array to device, CUDA array to CUDA array), cuMemcpy2D() may fail for pitches not computed by cuMemAllocPitch(). cuMemcpy2DUnaligned() does not have this restriction, but may run significantly slower in the cases where cuMemcpy2D() would have returned an error code.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpy2DAsync ( const CUDA_MEMCPY2D* pCopy, CUstream hStream )

Copies memory for 2D arrays.

Parameters

pCopy: - Parameters for the memory copy
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Perform a 2D memory copy according to the parameters specified in pCopy. The CUDA_MEMCPY2D structure is defined as:

‎   typedef struct CUDA_MEMCPY2D_st {
            unsigned int srcXInBytes, srcY;
            CUmemorytype srcMemoryType;
            const void *srcHost;
            CUdeviceptr srcDevice;
            CUarray srcArray;
            unsigned int srcPitch;
            unsigned int dstXInBytes, dstY;
            CUmemorytype dstMemoryType;
            void *dstHost;
            CUdeviceptr dstDevice;
            CUarray dstArray;
            unsigned int dstPitch;
            unsigned int WidthInBytes;
            unsigned int Height;
         } CUDA_MEMCPY2D;

where:

srcMemoryType and dstMemoryType specify the type of memory of the source and destination, respectively; CUmemorytype_enum is defined as:

‎   typedef enum CUmemorytype_enum {
            CU_MEMORYTYPE_HOST = 0x01,
            CU_MEMORYTYPE_DEVICE = 0x02,
            CU_MEMORYTYPE_ARRAY = 0x03,
            CU_MEMORYTYPE_UNIFIED = 0x04
         } CUmemorytype;

If srcMemoryType is CU_MEMORYTYPE_HOST, srcHost and srcPitch specify the (host) base address of the source data and the bytes per row to apply. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_DEVICE, srcDevice and srcPitch specify the (device) base address of the source data and the bytes per row to apply. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_ARRAY, srcArray specifies the handle of the source data. srcHost, srcDevice and srcPitch are ignored.

If dstMemoryType is CU_MEMORYTYPE_HOST, dstHost and dstPitch specify the (host) base address of the destination data and the bytes per row to apply. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_DEVICE, dstDevice and dstPitch specify the (device) base address of the destination data and the bytes per row to apply. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_ARRAY, dstArray specifies the handle of the destination data. dstHost, dstDevice and dstPitch are ignored.

srcXInBytes and srcY specify the base address of the source data for the copy.

For host pointers, the starting address is

‎  void* Start = (void*)((char*)srcHost+srcY*srcPitch + srcXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr Start = srcDevice+srcY*srcPitch+srcXInBytes;

For CUDA arrays, srcXInBytes must be evenly divisible by the array element size.

dstXInBytes and dstY specify the base address of the destination data for the copy.

For host pointers, the base address is

‎  void* dstStart = (void*)((char*)dstHost+dstY*dstPitch + dstXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr dstStart = dstDevice+dstY*dstPitch+dstXInBytes;

For CUDA arrays, dstXInBytes must be evenly divisible by the array element size.

WidthInBytes and Height specify the width (in bytes) and height of the 2D copy being performed.
If specified, srcPitch must be greater than or equal to WidthInBytes + srcXInBytes, and dstPitch must be greater than or equal to WidthInBytes + dstXInBytes.
If specified, srcPitch must be greater than or equal to WidthInBytes + srcXInBytes, and dstPitch must be greater than or equal to WidthInBytes + dstXInBytes.
If specified, srcHeight must be greater than or equal to Height + srcY, and dstHeight must be greater than or equal to Height + dstY.

cuMemcpy2DAsync() returns an error if any pitch is greater than the maximum allowed (CU_DEVICE_ATTRIBUTE_MAX_PITCH). cuMemAllocPitch() passes back pitches that always work with cuMemcpy2D(). On intra-device memory copies (device to device, CUDA array to device, CUDA array to CUDA array), cuMemcpy2DAsync() may fail for pitches not computed by cuMemAllocPitch().

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpy2DUnaligned ( const CUDA_MEMCPY2D* pCopy )

Copies memory for 2D arrays.

Parameters

pCopy: - Parameters for the memory copy

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Perform a 2D memory copy according to the parameters specified in pCopy. The CUDA_MEMCPY2D structure is defined as:

‎   typedef struct CUDA_MEMCPY2D_st {
            unsigned int srcXInBytes, srcY;
            CUmemorytype srcMemoryType;
            const void *srcHost;
            CUdeviceptr srcDevice;
            CUarray srcArray;
            unsigned int srcPitch;
            unsigned int dstXInBytes, dstY;
            CUmemorytype dstMemoryType;
            void *dstHost;
            CUdeviceptr dstDevice;
            CUarray dstArray;
            unsigned int dstPitch;
            unsigned int WidthInBytes;
            unsigned int Height;
         } CUDA_MEMCPY2D;

where:

srcMemoryType and dstMemoryType specify the type of memory of the source and destination, respectively; CUmemorytype_enum is defined as:

‎   typedef enum CUmemorytype_enum {
            CU_MEMORYTYPE_HOST = 0x01,
            CU_MEMORYTYPE_DEVICE = 0x02,
            CU_MEMORYTYPE_ARRAY = 0x03,
            CU_MEMORYTYPE_UNIFIED = 0x04
         } CUmemorytype;

If srcMemoryType is CU_MEMORYTYPE_HOST, srcHost and srcPitch specify the (host) base address of the source data and the bytes per row to apply. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_DEVICE, srcDevice and srcPitch specify the (device) base address of the source data and the bytes per row to apply. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_ARRAY, srcArray specifies the handle of the source data. srcHost, srcDevice and srcPitch are ignored.

If dstMemoryType is CU_MEMORYTYPE_HOST, dstHost and dstPitch specify the (host) base address of the destination data and the bytes per row to apply. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_DEVICE, dstDevice and dstPitch specify the (device) base address of the destination data and the bytes per row to apply. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_ARRAY, dstArray specifies the handle of the destination data. dstHost, dstDevice and dstPitch are ignored.

srcXInBytes and srcY specify the base address of the source data for the copy.

For host pointers, the starting address is

‎  void* Start = (void*)((char*)srcHost+srcY*srcPitch + srcXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr Start = srcDevice+srcY*srcPitch+srcXInBytes;

For CUDA arrays, srcXInBytes must be evenly divisible by the array element size.

dstXInBytes and dstY specify the base address of the destination data for the copy.

For host pointers, the base address is

‎  void* dstStart = (void*)((char*)dstHost+dstY*dstPitch + dstXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr dstStart = dstDevice+dstY*dstPitch+dstXInBytes;

For CUDA arrays, dstXInBytes must be evenly divisible by the array element size.

WidthInBytes and Height specify the width (in bytes) and height of the 2D copy being performed.
If specified, srcPitch must be greater than or equal to WidthInBytes + srcXInBytes, and dstPitch must be greater than or equal to WidthInBytes + dstXInBytes.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpy3D ( const CUDA_MEMCPY3D* pCopy )

Copies memory for 3D arrays.

Parameters

pCopy: - Parameters for the memory copy

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Perform a 3D memory copy according to the parameters specified in pCopy. The CUDA_MEMCPY3D structure is defined as:

‎        typedef struct CUDA_MEMCPY3D_st {
      
                  unsigned int srcXInBytes, srcY, srcZ;
                  unsigned int srcLOD;
                  CUmemorytype srcMemoryType;
                      const void *srcHost;
                      CUdeviceptr srcDevice;
                      CUarray srcArray;
                      unsigned int srcPitch;  // ignored when src is array
                      unsigned int srcHeight; // ignored when src is array; may be 0 if Depth==1
      
                  unsigned int dstXInBytes, dstY, dstZ;
                  unsigned int dstLOD;
                  CUmemorytype dstMemoryType;
                      void *dstHost;
                      CUdeviceptr dstDevice;
                      CUarray dstArray;
                      unsigned int dstPitch;  // ignored when dst is array
                      unsigned int dstHeight; // ignored when dst is array; may be 0 if Depth==1
      
                  unsigned int WidthInBytes;
                  unsigned int Height;
                  unsigned int Depth;
              } CUDA_MEMCPY3D;

where:

srcMemoryType and dstMemoryType specify the type of memory of the source and destination, respectively; CUmemorytype_enum is defined as:

‎   typedef enum CUmemorytype_enum {
            CU_MEMORYTYPE_HOST = 0x01,
            CU_MEMORYTYPE_DEVICE = 0x02,
            CU_MEMORYTYPE_ARRAY = 0x03,
            CU_MEMORYTYPE_UNIFIED = 0x04
         } CUmemorytype;

If srcMemoryType is CU_MEMORYTYPE_HOST, srcHost, srcPitch and srcHeight specify the (host) base address of the source data, the bytes per row, and the height of each 2D slice of the 3D array. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_DEVICE, srcDevice, srcPitch and srcHeight specify the (device) base address of the source data, the bytes per row, and the height of each 2D slice of the 3D array. srcArray is ignored.

If srcMemoryType is CU_MEMORYTYPE_ARRAY, srcArray specifies the handle of the source data. srcHost, srcDevice, srcPitch and srcHeight are ignored.

If dstMemoryType is CU_MEMORYTYPE_HOST, dstHost and dstPitch specify the (host) base address of the destination data, the bytes per row, and the height of each 2D slice of the 3D array. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_DEVICE, dstDevice and dstPitch specify the (device) base address of the destination data, the bytes per row, and the height of each 2D slice of the 3D array. dstArray is ignored.

If dstMemoryType is CU_MEMORYTYPE_ARRAY, dstArray specifies the handle of the destination data. dstHost, dstDevice, dstPitch and dstHeight are ignored.

srcXInBytes, srcY and srcZ specify the base address of the source data for the copy.

For host pointers, the starting address is

‎  void* Start = (void*)((char*)srcHost+(srcZ*srcHeight+srcY)*srcPitch + srcXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr Start = srcDevice+(srcZ*srcHeight+srcY)*srcPitch+srcXInBytes;

For CUDA arrays, srcXInBytes must be evenly divisible by the array element size.

dstXInBytes, dstY and dstZ specify the base address of the destination data for the copy.

For host pointers, the base address is

‎  void* dstStart = (void*)((char*)dstHost+(dstZ*dstHeight+dstY)*dstPitch + dstXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr dstStart = dstDevice+(dstZ*dstHeight+dstY)*dstPitch+dstXInBytes;

For CUDA arrays, dstXInBytes must be evenly divisible by the array element size.

WidthInBytes, Height and Depth specify the width (in bytes), height and depth of the 3D copy being performed.
If specified, srcPitch must be greater than or equal to WidthInBytes + srcXInBytes, and dstPitch must be greater than or equal to WidthInBytes + dstXInBytes.
If specified, srcHeight must be greater than or equal to Height + srcY, and dstHeight must be greater than or equal to Height + dstY.

cuMemcpy3D() returns an error if any pitch is greater than the maximum allowed (CU_DEVICE_ATTRIBUTE_MAX_PITCH).

The srcLOD and dstLOD members of the CUDA_MEMCPY3D structure must be set to 0.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpy3DAsync ( const CUDA_MEMCPY3D* pCopy, CUstream hStream )

Copies memory for 3D arrays.

Parameters

pCopy: - Parameters for the memory copy
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Perform a 3D memory copy according to the parameters specified in pCopy. The CUDA_MEMCPY3D structure is defined as:

‎        typedef struct CUDA_MEMCPY3D_st {
      
                  unsigned int srcXInBytes, srcY, srcZ;
                  unsigned int srcLOD;
                  CUmemorytype srcMemoryType;
                      const void *srcHost;
                      CUdeviceptr srcDevice;
                      CUarray srcArray;
                      unsigned int srcPitch;  // ignored when src is array
                      unsigned int srcHeight; // ignored when src is array; may be 0 if Depth==1
      
                  unsigned int dstXInBytes, dstY, dstZ;
                  unsigned int dstLOD;
                  CUmemorytype dstMemoryType;
                      void *dstHost;
                      CUdeviceptr dstDevice;
                      CUarray dstArray;
                      unsigned int dstPitch;  // ignored when dst is array
                      unsigned int dstHeight; // ignored when dst is array; may be 0 if Depth==1
      
                  unsigned int WidthInBytes;
                  unsigned int Height;
                  unsigned int Depth;
              } CUDA_MEMCPY3D;

where:

srcMemoryType and dstMemoryType specify the type of memory of the source and destination, respectively; CUmemorytype_enum is defined as:

‎   typedef enum CUmemorytype_enum {
            CU_MEMORYTYPE_HOST = 0x01,
            CU_MEMORYTYPE_DEVICE = 0x02,
            CU_MEMORYTYPE_ARRAY = 0x03,
            CU_MEMORYTYPE_UNIFIED = 0x04
         } CUmemorytype;

If srcMemoryType is CU_MEMORYTYPE_ARRAY, srcArray specifies the handle of the source data. srcHost, srcDevice, srcPitch and srcHeight are ignored.

If dstMemoryType is CU_MEMORYTYPE_ARRAY, dstArray specifies the handle of the destination data. dstHost, dstDevice, dstPitch and dstHeight are ignored.

srcXInBytes, srcY and srcZ specify the base address of the source data for the copy.

For host pointers, the starting address is

‎  void* Start = (void*)((char*)srcHost+(srcZ*srcHeight+srcY)*srcPitch + srcXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr Start = srcDevice+(srcZ*srcHeight+srcY)*srcPitch+srcXInBytes;

For CUDA arrays, srcXInBytes must be evenly divisible by the array element size.

dstXInBytes, dstY and dstZ specify the base address of the destination data for the copy.

For host pointers, the base address is

‎  void* dstStart = (void*)((char*)dstHost+(dstZ*dstHeight+dstY)*dstPitch + dstXInBytes);

For device pointers, the starting address is

‎  CUdeviceptr dstStart = dstDevice+(dstZ*dstHeight+dstY)*dstPitch+dstXInBytes;

For CUDA arrays, dstXInBytes must be evenly divisible by the array element size.

WidthInBytes, Height and Depth specify the width (in bytes), height and depth of the 3D copy being performed.
If specified, srcPitch must be greater than or equal to WidthInBytes + srcXInBytes, and dstPitch must be greater than or equal to WidthInBytes + dstXInBytes.
If specified, srcHeight must be greater than or equal to Height + srcY, and dstHeight must be greater than or equal to Height + dstY.

cuMemcpy3DAsync() returns an error if any pitch is greater than the maximum allowed (CU_DEVICE_ATTRIBUTE_MAX_PITCH).

The srcLOD and dstLOD members of the CUDA_MEMCPY3D structure must be set to 0.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpy3DPeer ( const CUDA_MEMCPY3D_PEER* pCopy )

Copies memory between contexts.

Parameters

pCopy: - Parameters for the memory copy

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Perform a 3D memory copy according to the parameters specified in pCopy. See the definition of the CUDA_MEMCPY3D_PEER structure for documentation of its parameters.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpy3DPeerAsync ( const CUDA_MEMCPY3D_PEER* pCopy, CUstream hStream )

Copies memory between contexts asynchronously.

Parameters

pCopy: - Parameters for the memory copy
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Perform a 3D memory copy according to the parameters specified in pCopy. See the definition of the CUDA_MEMCPY3D_PEER structure for documentation of its parameters.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpyAsync ( CUdeviceptr dst, CUdeviceptr src, size_t ByteCount, CUstream hStream )

Copies memory asynchronously.

Parameters

dst: - Destination unified virtual address space pointer
src: - Source unified virtual address space pointer
ByteCount: - Size of memory copy in bytes
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpyAtoA ( CUarray dstArray, size_t dstOffset, CUarray srcArray, size_t srcOffset, size_t ByteCount )

Copies memory from Array to Array.

Parameters

dstArray: - Destination array
dstOffset: - Offset in bytes of destination array
srcArray: - Source array
srcOffset: - Offset in bytes of source array
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from one 1D CUDA array to another. dstArray and srcArray specify the handles of the destination and source CUDA arrays for the copy, respectively. dstOffset and srcOffset specify the destination and source offsets in bytes into the CUDA arrays. ByteCount is the number of bytes to be copied. The size of the elements in the CUDA arrays need not be the same format, but the elements must be the same size; and count must be evenly divisible by that size.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyAtoD ( CUdeviceptr dstDevice, CUarray srcArray, size_t srcOffset, size_t ByteCount )

Copies memory from Array to Device.

Parameters

dstDevice: - Destination device pointer
srcArray: - Source array
srcOffset: - Offset in bytes of source array
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from one 1D CUDA array to device memory. dstDevice specifies the base pointer of the destination and must be naturally aligned with the CUDA array elements. srcArray and srcOffset specify the CUDA array handle and the offset in bytes into the array where the copy is to begin. ByteCount specifies the number of bytes to copy and must be evenly divisible by the array element size.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyAtoH ( void* dstHost, CUarray srcArray, size_t srcOffset, size_t ByteCount )

Copies memory from Array to Host.

Parameters

dstHost: - Destination device pointer
srcArray: - Source array
srcOffset: - Offset in bytes of source array
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from one 1D CUDA array to host memory. dstHost specifies the base pointer of the destination. srcArray and srcOffset specify the CUDA array handle and starting offset in bytes of the source data. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyAtoHAsync ( void* dstHost, CUarray srcArray, size_t srcOffset, size_t ByteCount, CUstream hStream )

Copies memory from Array to Host.

Parameters

dstHost: - Destination pointer
srcArray: - Source array
srcOffset: - Offset in bytes of source array
ByteCount: - Size of memory copy in bytes
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpyDtoA ( CUarray dstArray, size_t dstOffset, CUdeviceptr srcDevice, size_t ByteCount )

Copies memory from Device to Array.

Parameters

dstArray: - Destination array
dstOffset: - Offset in bytes of destination array
srcDevice: - Source device pointer
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from device memory to a 1D CUDA array. dstArray and dstOffset specify the CUDA array handle and starting index of the destination data. srcDevice specifies the base pointer of the source. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyDtoD ( CUdeviceptr dstDevice, CUdeviceptr srcDevice, size_t ByteCount )

Copies memory from Device to Device.

Parameters

dstDevice: - Destination device pointer
srcDevice: - Source device pointer
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from device memory to device memory. dstDevice and srcDevice are the base pointers of the destination and source, respectively. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyDtoDAsync ( CUdeviceptr dstDevice, CUdeviceptr srcDevice, size_t ByteCount, CUstream hStream )

Copies memory from Device to Device.

Parameters

dstDevice: - Destination device pointer
srcDevice: - Source device pointer
ByteCount: - Size of memory copy in bytes
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from device memory to device memory. dstDevice and srcDevice are the base pointers of the destination and source, respectively. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpyDtoH ( void* dstHost, CUdeviceptr srcDevice, size_t ByteCount )

Copies memory from Device to Host.

Parameters

dstHost: - Destination host pointer
srcDevice: - Source device pointer
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from device to host memory. dstHost and srcDevice specify the base pointers of the destination and source, respectively. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyDtoHAsync ( void* dstHost, CUdeviceptr srcDevice, size_t ByteCount, CUstream hStream )

Copies memory from Device to Host.

Parameters

dstHost: - Destination host pointer
srcDevice: - Source device pointer
ByteCount: - Size of memory copy in bytes
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from device to host memory. dstHost and srcDevice specify the base pointers of the destination and source, respectively. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpyHtoA ( CUarray dstArray, size_t dstOffset, const void* srcHost, size_t ByteCount )

Copies memory from Host to Array.

Parameters

dstArray: - Destination array
dstOffset: - Offset in bytes of destination array
srcHost: - Source host pointer
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from host memory to a 1D CUDA array. dstArray and dstOffset specify the CUDA array handle and starting offset in bytes of the destination data. pSrc specifies the base address of the source. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyHtoAAsync ( CUarray dstArray, size_t dstOffset, const void* srcHost, size_t ByteCount, CUstream hStream )

Copies memory from Host to Array.

Parameters

dstArray: - Destination array
dstOffset: - Offset in bytes of destination array
srcHost: - Source host pointer
ByteCount: - Size of memory copy in bytes
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from host memory to a 1D CUDA array. dstArray and dstOffset specify the CUDA array handle and starting offset in bytes of the destination data. srcHost specifies the base address of the source. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpyHtoD ( CUdeviceptr dstDevice, const void* srcHost, size_t ByteCount )

Copies memory from Host to Device.

Parameters

dstDevice: - Destination device pointer
srcHost: - Source host pointer
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from host memory to device memory. dstDevice and srcHost are the base addresses of the destination and source, respectively. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyHtoDAsync ( CUdeviceptr dstDevice, const void* srcHost, size_t ByteCount, CUstream hStream )

Copies memory from Host to Device.

Parameters

dstDevice: - Destination device pointer
srcHost: - Source host pointer
ByteCount: - Size of memory copy in bytes
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from host memory to device memory. dstDevice and srcHost are the base addresses of the destination and source, respectively. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemcpyPeer ( CUdeviceptr dstDevice, CUcontext dstContext, CUdeviceptr srcDevice, CUcontext srcContext, size_t ByteCount )

Copies device memory between two contexts.

Parameters

dstDevice: - Destination device pointer
dstContext: - Destination context
srcDevice: - Source device pointer
srcContext: - Source context
ByteCount: - Size of memory copy in bytes

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Copies from device memory in one context to device memory in another context. dstDevice is the base device pointer of the destination memory and dstContext is the destination context. srcDevice is the base device pointer of the source memory and srcContext is the source pointer. ByteCount specifies the number of bytes to copy.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits synchronous behavior for most use cases.

CUresult cuMemcpyPeerAsync ( CUdeviceptr dstDevice, CUcontext dstContext, CUdeviceptr srcDevice, CUcontext srcContext, size_t ByteCount, CUstream hStream )

Copies device memory between two contexts asynchronously.

Parameters

dstDevice: - Destination device pointer
dstContext: - Destination context
srcDevice: - Source device pointer
srcContext: - Source context
ByteCount: - Size of memory copy in bytes
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Note:

Note that this function may also return error codes from previous, asynchronous launches.
This function exhibits asynchronous behavior for most use cases.
This function uses standard default stream semantics.

CUresult cuMemsetD16 ( CUdeviceptr dstDevice, unsigned short us, size_t N )

Initializes device memory.

Parameters

dstDevice: - Destination device pointer
us: - Value to set
N: - Number of elements

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the memory range of N 16-bit values to the specified value us. The dstDevice pointer must be two byte aligned.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.

CUresult cuMemsetD16Async ( CUdeviceptr dstDevice, unsigned short us, size_t N, CUstream hStream )

Sets device memory.

Parameters

dstDevice: - Destination device pointer
us: - Value to set
N: - Number of elements
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the memory range of N 16-bit values to the specified value us. The dstDevice pointer must be two byte aligned.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.
This function uses standard default stream semantics.

CUresult cuMemsetD2D16 ( CUdeviceptr dstDevice, size_t dstPitch, unsigned short us, size_t Width, size_t Height )

Initializes device memory.

Parameters

dstDevice: - Destination device pointer
dstPitch: - Pitch of destination device pointer
us: - Value to set
Width: - Width of row
Height: - Number of rows

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the 2D memory range of Width 16-bit values to the specified value us. Height specifies the number of rows to set, and dstPitch specifies the number of bytes between each row. The dstDevice pointer and dstPitch offset must be two byte aligned. This function performs fastest when the pitch is one that has been passed back by cuMemAllocPitch().

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.

CUresult cuMemsetD2D16Async ( CUdeviceptr dstDevice, size_t dstPitch, unsigned short us, size_t Width, size_t Height, CUstream hStream )

Sets device memory.

Parameters

dstDevice: - Destination device pointer
dstPitch: - Pitch of destination device pointer
us: - Value to set
Width: - Width of row
Height: - Number of rows
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.
This function uses standard default stream semantics.

CUresult cuMemsetD2D32 ( CUdeviceptr dstDevice, size_t dstPitch, unsigned int ui, size_t Width, size_t Height )

Initializes device memory.

Parameters

dstDevice: - Destination device pointer
dstPitch: - Pitch of destination device pointer
ui: - Value to set
Width: - Width of row
Height: - Number of rows

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the 2D memory range of Width 32-bit values to the specified value ui. Height specifies the number of rows to set, and dstPitch specifies the number of bytes between each row. The dstDevice pointer and dstPitch offset must be four byte aligned. This function performs fastest when the pitch is one that has been passed back by cuMemAllocPitch().

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.

CUresult cuMemsetD2D32Async ( CUdeviceptr dstDevice, size_t dstPitch, unsigned int ui, size_t Width, size_t Height, CUstream hStream )

Sets device memory.

Parameters

dstDevice: - Destination device pointer
dstPitch: - Pitch of destination device pointer
ui: - Value to set
Width: - Width of row
Height: - Number of rows
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.
This function uses standard default stream semantics.

CUresult cuMemsetD2D8 ( CUdeviceptr dstDevice, size_t dstPitch, unsigned char uc, size_t Width, size_t Height )

Initializes device memory.

Parameters

dstDevice: - Destination device pointer
dstPitch: - Pitch of destination device pointer
uc: - Value to set
Width: - Width of row
Height: - Number of rows

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the 2D memory range of Width 8-bit values to the specified value uc. Height specifies the number of rows to set, and dstPitch specifies the number of bytes between each row. This function performs fastest when the pitch is one that has been passed back by cuMemAllocPitch().

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.

CUresult cuMemsetD2D8Async ( CUdeviceptr dstDevice, size_t dstPitch, unsigned char uc, size_t Width, size_t Height, CUstream hStream )

Sets device memory.

Parameters

dstDevice: - Destination device pointer
dstPitch: - Pitch of destination device pointer
uc: - Value to set
Width: - Width of row
Height: - Number of rows
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.
This function uses standard default stream semantics.

CUresult cuMemsetD32 ( CUdeviceptr dstDevice, unsigned int ui, size_t N )

Initializes device memory.

Parameters

dstDevice: - Destination device pointer
ui: - Value to set
N: - Number of elements

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the memory range of N 32-bit values to the specified value ui. The dstDevice pointer must be four byte aligned.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.

CUresult cuMemsetD32Async ( CUdeviceptr dstDevice, unsigned int ui, size_t N, CUstream hStream )

Sets device memory.

Parameters

dstDevice: - Destination device pointer
ui: - Value to set
N: - Number of elements
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the memory range of N 32-bit values to the specified value ui. The dstDevice pointer must be four byte aligned.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.
This function uses standard default stream semantics.

CUresult cuMemsetD8 ( CUdeviceptr dstDevice, unsigned char uc, size_t N )

Initializes device memory.

Parameters

dstDevice: - Destination device pointer
uc: - Value to set
N: - Number of elements

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the memory range of N 8-bit values to the specified value uc.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.

CUresult cuMemsetD8Async ( CUdeviceptr dstDevice, unsigned char uc, size_t N, CUstream hStream )

Sets device memory.

Parameters

dstDevice: - Destination device pointer
uc: - Value to set
N: - Number of elements
hStream: - Stream identifier

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

Description

Sets the memory range of N 8-bit values to the specified value uc.

Note:

Note that this function may also return error codes from previous, asynchronous launches.
See also memset synchronization details.
This function uses standard default stream semantics.

CUresult cuMipmappedArrayCreate ( CUmipmappedArray* pHandle, const CUDA_ARRAY3D_DESCRIPTOR* pMipmappedArrayDesc, unsigned int numMipmapLevels )

Creates a CUDA mipmapped array.

Parameters

pHandle: - Returned mipmapped array
pMipmappedArrayDesc: - mipmapped array descriptor
numMipmapLevels: - Number of mipmap levels

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_OUT_OF_MEMORY, CUDA_ERROR_UNKNOWN

Description

Creates a CUDA mipmapped array according to the CUDA_ARRAY3D_DESCRIPTOR structure pMipmappedArrayDesc and returns a handle to the new CUDA mipmapped array in *pHandle. numMipmapLevels specifies the number of mipmap levels to be allocated. This value is clamped to the range [1, 1 + floor(log2(max(width, height, depth)))].

The CUDA_ARRAY3D_DESCRIPTOR is defined as:

‎    typedef struct {
              unsigned int Width;
              unsigned int Height;
              unsigned int Depth;
              CUarray_format Format;
              unsigned int NumChannels;
              unsigned int Flags;
          } CUDA_ARRAY3D_DESCRIPTOR;

where:

Width, Height, and Depth are the width, height, and depth of the CUDA array (in elements); the following types of CUDA arrays can be allocated:
- A 1D mipmapped array is allocated if Height and Depth extents are both zero.
- A 2D mipmapped array is allocated if only Depth extent is zero.
- A 3D mipmapped array is allocated if all three extents are non-zero.
- A 1D layered CUDA mipmapped array is allocated if only Height is zero and the CUDA_ARRAY3D_LAYERED flag is set. Each layer is a 1D array. The number of layers is determined by the depth extent.
- A 2D layered CUDA mipmapped array is allocated if all three extents are non-zero and the CUDA_ARRAY3D_LAYERED flag is set. Each layer is a 2D array. The number of layers is determined by the depth extent.
- A cubemap CUDA mipmapped array is allocated if all three extents are non-zero and the CUDA_ARRAY3D_CUBEMAP flag is set. Width must be equal to Height, and Depth must be six. A cubemap is a special type of 2D layered CUDA array, where the six layers represent the six faces of a cube. The order of the six layers in memory is the same as that listed in CUarray_cubemap_face.
- A cubemap layered CUDA mipmapped array is allocated if all three extents are non-zero, and both, CUDA_ARRAY3D_CUBEMAP and CUDA_ARRAY3D_LAYERED flags are set. Width must be equal to Height, and Depth must be a multiple of six. A cubemap layered CUDA array is a special type of 2D layered CUDA array that consists of a collection of cubemaps. The first six layers represent the first cubemap, the next six layers form the second cubemap, and so on.

Format specifies the format of the elements; CUarray_format is defined as:

‎    typedef enum CUarray_format_enum {
              CU_AD_FORMAT_UNSIGNED_INT8 = 0x01,
              CU_AD_FORMAT_UNSIGNED_INT16 = 0x02,
              CU_AD_FORMAT_UNSIGNED_INT32 = 0x03,
              CU_AD_FORMAT_SIGNED_INT8 = 0x08,
              CU_AD_FORMAT_SIGNED_INT16 = 0x09,
              CU_AD_FORMAT_SIGNED_INT32 = 0x0a,
              CU_AD_FORMAT_HALF = 0x10,
              CU_AD_FORMAT_FLOAT = 0x20
          } CUarray_format;

NumChannels specifies the number of packed components per CUDA array element; it may be 1, 2, or 4;

Flags may be set to
- CUDA_ARRAY3D_LAYERED to enable creation of layered CUDA mipmapped arrays. If this flag is set, Depth specifies the number of layers, not the depth of a 3D array.
- CUDA_ARRAY3D_SURFACE_LDST to enable surface references to be bound to individual mipmap levels of the CUDA mipmapped array. If this flag is not set, cuSurfRefSetArray will fail when attempting to bind a mipmap level of the CUDA mipmapped array to a surface reference.
- CUDA_ARRAY3D_CUBEMAP to enable creation of mipmapped cubemaps. If this flag is set, Width must be equal to Height, and Depth must be six. If the CUDA_ARRAY3D_LAYERED flag is also set, then Depth must be a multiple of six.
- CUDA_ARRAY3D_TEXTURE_GATHER to indicate that the CUDA mipmapped array will be used for texture gather. Texture gather can only be performed on 2D CUDA mipmapped arrays.

Width, Height and Depth must meet certain size requirements as listed in the following table. All values are specified in elements. Note that for brevity's sake, the full name of the device attribute is not specified. For ex., TEXTURE1D_MIPMAPPED_WIDTH refers to the device attribute CU_DEVICE_ATTRIBUTE_MAXIMUM_TEXTURE1D_MIPMAPPED_WIDTH.

CUDA array type	Valid extents that must always be met {(width range in elements), (height range), (depth range)}	Valid extents with CUDA_ARRAY3D_SURFACE_LDST set {(width range in elements), (height range), (depth range)}
1D	{ (1,TEXTURE1D_MIPMAPPED_WIDTH), 0, 0 }	{ (1,SURFACE1D_WIDTH), 0, 0 }
2D	{ (1,TEXTURE2D_MIPMAPPED_WIDTH), (1,TEXTURE2D_MIPMAPPED_HEIGHT), 0 }	{ (1,SURFACE2D_WIDTH), (1,SURFACE2D_HEIGHT), 0 }
3D	{ (1,TEXTURE3D_WIDTH), (1,TEXTURE3D_HEIGHT), (1,TEXTURE3D_DEPTH) } OR { (1,TEXTURE3D_WIDTH_ALTERNATE), (1,TEXTURE3D_HEIGHT_ALTERNATE), (1,TEXTURE3D_DEPTH_ALTERNATE) }	{ (1,SURFACE3D_WIDTH), (1,SURFACE3D_HEIGHT), (1,SURFACE3D_DEPTH) }
1D Layered	{ (1,TEXTURE1D_LAYERED_WIDTH), 0, (1,TEXTURE1D_LAYERED_LAYERS) }	{ (1,SURFACE1D_LAYERED_WIDTH), 0, (1,SURFACE1D_LAYERED_LAYERS) }
2D Layered	{ (1,TEXTURE2D_LAYERED_WIDTH), (1,TEXTURE2D_LAYERED_HEIGHT), (1,TEXTURE2D_LAYERED_LAYERS) }	{ (1,SURFACE2D_LAYERED_WIDTH), (1,SURFACE2D_LAYERED_HEIGHT), (1,SURFACE2D_LAYERED_LAYERS) }
Cubemap	{ (1,TEXTURECUBEMAP_WIDTH), (1,TEXTURECUBEMAP_WIDTH), 6 }	{ (1,SURFACECUBEMAP_WIDTH), (1,SURFACECUBEMAP_WIDTH), 6 }
Cubemap Layered	{ (1,TEXTURECUBEMAP_LAYERED_WIDTH), (1,TEXTURECUBEMAP_LAYERED_WIDTH), (1,TEXTURECUBEMAP_LAYERED_LAYERS) }	{ (1,SURFACECUBEMAP_LAYERED_WIDTH), (1,SURFACECUBEMAP_LAYERED_WIDTH), (1,SURFACECUBEMAP_LAYERED_LAYERS) }

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMipmappedArrayDestroy ( CUmipmappedArray hMipmappedArray )

Destroys a CUDA mipmapped array.

Parameters

hMipmappedArray: - Mipmapped array to destroy

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_HANDLE, CUDA_ERROR_ARRAY_IS_MAPPED

Description

Destroys the CUDA mipmapped array hMipmappedArray.

Note:

Note that this function may also return error codes from previous, asynchronous launches.

CUresult cuMipmappedArrayGetLevel ( CUarray* pLevelArray, CUmipmappedArray hMipmappedArray, unsigned int level )

Gets a mipmap level of a CUDA mipmapped array.

Parameters

pLevelArray: - Returned mipmap level CUDA array
hMipmappedArray: - CUDA mipmapped array
level: - Mipmap level

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_INVALID_HANDLE

Description

Returns in *pLevelArray a CUDA array that represents a single mipmap level of the CUDA mipmapped array hMipmappedArray.

If level is greater than the maximum number of levels in this mipmapped array, CUDA_ERROR_INVALID_VALUE is returned.

Note:

Note that this function may also return error codes from previous, asynchronous launches.