cupy.cuda.MemoryPointer

class cupy.cuda.MemoryPointer

Pointer to a point on a device memory.

An instance of this class holds a reference to the original memory buffer and a pointer to a place within this buffer.

Parameters:

• mem (Memory) – The device memory buffer.
• offset (int) – An offset from the head of the buffer to the place this pointer refers.

Variables:

• device (cupy.cuda.Device) – Device whose memory the pointer refers to.
• mem (Memory) – The device memory buffer.
• ptr (int) – Pointer to the place within the buffer.

Methods

copy_from()

Copies a memory sequence from a (possibly different) device or host.

This function is a useful interface that selects appropriate one from copy_from_device() and copy_from_host().

Parameters:

• mem (ctypes.c_void_p or cupy.cuda.MemoryPointer) – Source memory pointer.
• size (int) – Size of the sequence in bytes.

copy_from_async()

Copies a memory sequence from an arbitrary place asynchronously.

This function is a useful interface that selects appropriate one from copy_from_device_async() and copy_from_host_async().

Parameters:

• mem (ctypes.c_void_p or cupy.cuda.MemoryPointer) – Source memory pointer.
• size (int) – Size of the sequence in bytes.
• stream (cupy.cuda.Stream) – CUDA stream.

copy_from_device()

Copies a memory sequence from a (possibly different) device.

Parameters:

• src (cupy.cuda.MemoryPointer) – Source memory pointer.
• size (int) – Size of the sequence in bytes.

copy_from_device_async()

Copies a memory from a (possibly different) device asynchronously.

Parameters:

• src (cupy.cuda.MemoryPointer) – Source memory pointer.
• size (int) – Size of the sequence in bytes.
• stream (cupy.cuda.Stream) – CUDA stream.

copy_from_host()

Copies a memory sequence from the host memory.

Parameters:

• mem (ctypes.c_void_p) – Source memory pointer.
• size (int) – Size of the sequence in bytes.

copy_from_host_async()

Copies a memory sequence from the host memory asynchronously.

Parameters:

• mem (ctypes.c_void_p) – Source memory pointer. It must be a pinned memory.
• size (int) – Size of the sequence in bytes.
• stream (cupy.cuda.Stream) – CUDA stream.

copy_to_host()

Copies a memory sequence to the host memory.

Parameters:

• mem (ctypes.c_void_p) – Target memory pointer.
• size (int) – Size of the sequence in bytes.

copy_to_host_async()

Copies a memory sequence to the host memory asynchronously.

Parameters:

• mem (ctypes.c_void_p) – Target memory pointer. It must be a pinned memory.
• size (int) – Size of the sequence in bytes.
• stream (cupy.cuda.Stream) – CUDA stream.

memset()

Fills a memory sequence by constant byte value.

Parameters:

• value (int) – Value to fill.
• size (int) – Size of the sequence in bytes.

memset_async()

Fills a memory sequence by constant byte value asynchronously.

Parameters:

• value (int) – Value to fill.
• size (int) – Size of the sequence in bytes.
• stream (cupy.cuda.Stream) – CUDA stream.

Attributes

device

mem

ptr