rmm::mr::host_memory_resource Class Reference

Base class for host memory allocation. More...

#include <host_memory_resource.hpp>

Inheritance diagram for rmm::mr::host_memory_resource:

Public Member Functions
	host_memory_resource (host_memory_resource const &)=default
	Default copy constructor.
	host_memory_resource (host_memory_resource &&) noexcept=default
	Default move constructor.
host_memory_resource &	operator= (host_memory_resource const &)=default
	Default copy assignment operator. More...
host_memory_resource &	operator= (host_memory_resource &&) noexcept=default
	Default move assignment operator. More...
void *	allocate (std::size_t bytes, std::size_t alignment=alignof(std::max_align_t))
	Allocates memory on the host of size at least bytes bytes. More...
void	deallocate (void *ptr, std::size_t bytes, std::size_t alignment=alignof(std::max_align_t))
	Deallocate memory pointed to by ptr. More...
bool	is_equal (host_memory_resource const &other) const noexcept
	Compare this resource to another. More...

Detailed Description

Base class for host memory allocation.

This is based on std::pmr::memory_resource: https://en.cppreference.com/w/cpp/memory/memory_resource

When C++17 is available for use in RMM, rmm::host_memory_resource should inherit from std::pmr::memory_resource.

This class serves as the interface that all host memory resource implementations must satisfy.

There are two private, pure virtual functions that all derived classes must implement: do_allocate and do_deallocate. Optionally, derived classes may also override is_equal. By default, is_equal simply performs an identity comparison.

The public, non-virtual functions allocate, deallocate, and is_equal simply call the private virtual functions. The reason for this is to allow implementing shared, default behavior in the base class. For example, the base class' allocate function may log every allocation, no matter what derived class implementation is used.

Member Function Documentation

allocate()

void* rmm::mr::host_memory_resource::allocate ( std::size_t  bytes, std::size_t  alignment = alignof(std::max_align_t)  )

inline

Allocates memory on the host of size at least bytes bytes.

The returned storage is aligned to the specified alignment if supported, and to alignof(std::max_align_t) otherwise.

Exceptions

std::bad_alloc

When the requested bytes and alignment cannot be allocated.

Parameters

bytes	The size of the allocation
alignment	Alignment of the allocation

Returns

void* Pointer to the newly allocated memory

deallocate()

void rmm::mr::host_memory_resource::deallocate ( void *  ptr, std::size_t  bytes, std::size_t  alignment = alignof(std::max_align_t)  )

inline

Deallocate memory pointed to by ptr.

ptr must have been returned by a prior call to allocate(bytes,alignment) on a host_memory_resource that compares equal to *this, and the storage it points to must not yet have been deallocated, otherwise behavior is undefined.

Exceptions

Nothing.

Parameters

ptr	Pointer to be deallocated
bytes	The size in bytes of the allocation. This must be equal to the value of bytes that was passed to the allocate call that returned ptr.
alignment	Alignment of the allocation. This must be equal to the value of alignment that was passed to the allocate call that returned ptr.

is_equal()

bool rmm::mr::host_memory_resource::is_equal ( host_memory_resource const &  other ) const

inlinenoexcept

Compare this resource to another.

Two host_memory_resources compare equal if and only if memory allocated from one host_memory_resource can be deallocated from the other and vice versa.

By default, simply checks if *this and other refer to the same object, i.e., does not check if they are two objects of the same class.

Parameters

other

The other resource to compare to

Returns

true if the two resources are equivalent

operator=() [1/2]

host_memory_resource& rmm::mr::host_memory_resource::operator= ( host_memory_resource &&  )

defaultnoexcept

Default move assignment operator.

Returns

host_memory_resource& Reference to the assigned object

operator=() [2/2]

host_memory_resource& rmm::mr::host_memory_resource::operator= ( host_memory_resource const &  )

default

Default copy assignment operator.

Returns

host_memory_resource& Reference to the assigned object

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The documentation for this class was generated from the following file:

• host_memory_resource.hpp