AcceleratorBuffer< T > Class Template Reference

A buffer of memory which may be used by GPU acceleration. More...

#include <AcceleratorBuffer.h>

Inheritance diagram for AcceleratorBuffer< T >:

Collaboration diagram for AcceleratorBuffer< T >:

Public Types
enum	MemoryAttributes {   MEM_ATTRIB_CPU_SIDE = 0x1 , MEM_ATTRIB_GPU_SIDE = 0x2 , MEM_ATTRIB_CPU_REACHABLE = 0x4 , MEM_ATTRIB_GPU_REACHABLE = 0x8 ,   MEM_ATTRIB_CPU_FAST = 0x10 , MEM_ATTRIB_GPU_FAST = 0x20 }
	Attributes that a memory buffer can have.
enum	MemoryType {   MEM_TYPE_NULL = 0 , MEM_TYPE_CPU_PAGED , MEM_TYPE_CPU_ONLY , MEM_TYPE_CPU_DMA_CAPABLE ,   MEM_TYPE_GPU_ONLY , MEM_TYPE_GPU_DMA_CAPABLE }
	Types of memory buffer.
enum	UsageHint { HINT_NEVER , HINT_UNLIKELY , HINT_LIKELY }

Public Member Functions
virtual std::string	GetType () const
	Gets the underlying C++ object type.
virtual size_t	GetElementSize () const
	Gets the size of each entry in the container.
	__attribute__ ((noinline)) AcceleratorBuffer(const std
	Creates a new AcceleratorBuffer with no content.
size_t	GetMemoryBytes () const
	Returns the total size of the buffer (wherever it is), in bytes.
size_t	GetCpuMemoryBytes () const
	Returns the total reserved CPU memory, in bytes.
size_t	GetGpuMemoryBytes () const
	Returns the total reserved GPU memory, in bytes.
bool	empty () const
	Returns true if the container is empty.
bool	IsCpuBufferStale () const
	Returns true if the CPU-side buffer is stale.
bool	IsGpuBufferStale () const
	Returns true if the GPU-side buffer is stale.
bool	HasCpuBuffer () const
	Returns true if there is currently a CPU-side buffer.
bool	HasGpuBuffer () const
	Returns true if there is currently a GPU-side buffer.
bool	IsSingleSharedBuffer () const
	Returns true if the object contains only a single buffer.
vk::Buffer	GetBuffer ()
	Returns the preferred buffer for GPU-side access.
T *	GetCpuPointer ()
	Gets a pointer to the CPU-side buffer.
vk::DescriptorBufferInfo	GetBufferInfo ()
	Returns a vk::DescriptorBufferInfo suitable for binding this object to.
void	resize (size_t size, bool exactSize=false)
	Change the usable size of the container.
void	clear ()
	Resize the container to be empty (but don't free memory)
void	reserve (size_t size)
	Reallocates buffers so that at least size elements of storage are available.
void	shrink_to_fit ()
	Frees unused memory so that m_size == m_capacity.
	__attribute__ ((noinline)) void CopyFrom(const std
	Copies our content from a std::vector.
	__attribute__ ((noinline)) void CopyFrom(const AcceleratorBuffer< T > &rhs
	Copies our content from another AcceleratorBuffer.
bool	BeginHostDeviceTransferIfNeeded ()
	Starts a host-to-device transfer if we need to do one.
void	ClearTransferFlags ()
Public Member Functions inherited from AcceleratorBufferBase
	AcceleratorBufferBase (const std::string &name="")
size_t	size () const
	Returns the actual size of the container (may be smaller than what was allocated)
size_t	capacity () const
	Returns the allocated size of the container.
const std::string &	GetName () const
	Returns the debug name of the buffer, if any.

Public Attributes
bool	reallocateToMatch
std::unique_ptr< vk::raii::Event >	m_deviceHostTransferEvent
	Event signaled upon completion of a device-host transfer.
std::atomic< bool >	m_hostDeviceTransferActive
	True if a host-device transfer has been submitted.
std::unique_ptr< vk::raii::Event >	m_hostDeviceTransferEvent
	Event signaled upon completion of a host-device transfer.
Public Attributes inherited from AcceleratorBufferBase
size_t	m_capacity
	Size of the allocated memory space (may be larger than m_size)
size_t	m_size
	Size of the memory actually being used.

Protected Member Functions
bool	IsReachableFromCpu (MemoryType mt)
	Returns true if the given buffer type can be reached from the CPU.
bool	IsReachableFromGpu (MemoryType mt)
	Returns true if the given buffer type can be reached from the GPU.
bool	IsFastFromCpu (MemoryType mt)
	Returns true if the given buffer type is fast to access from the CPU.
bool	IsFastFromGpu (MemoryType mt)
	Returns true if the given buffer type is fast to access from the GPU.

Protected Attributes
AlignedAllocator< T, 32 >	m_cpuAllocator
MemoryType	m_cpuMemoryType
	Type of the CPU-side buffer.
MemoryType	m_gpuMemoryType
	Type of the GPU-side buffer.
T *	m_cpuPtr
	CPU-side mapped pointer.
std::unique_ptr< vk::raii::DeviceMemory >	m_cpuPhysMem
	CPU-side physical memory.
std::unique_ptr< vk::raii::DeviceMemory >	m_gpuPhysMem
	GPU-side physical memory.
std::unique_ptr< vk::raii::Buffer >	m_cpuBuffer
	Buffer object for CPU-side memory.
std::unique_ptr< vk::raii::Buffer >	m_gpuBuffer
	Buffer object for GPU-side memory.
bool	m_buffersAreSame
	True if we have only one piece of physical memory accessible from both sides.
bool	m_cpuPhysMemIsStale
	True if m_cpuPtr contains stale data (m_gpuPhysMem has been modified and they point to different memory)
bool	m_gpuPhysMemIsStale
	True if m_gpuPhysMem contains stale data (m_cpuPtr has been modified and they point to different memory)
int	m_tempFileHandle
	File handle used for MEM_TYPE_CPU_PAGED.
UsageHint	m_cpuAccessHint
	Hint about how likely future CPU access is.
UsageHint	m_gpuAccessHint
	Hint about how likely future GPU access is.
Protected Attributes inherited from AcceleratorBufferBase
std::string	m_name
	Friendly name of the buffer (for debug tools)

Additional Inherited Members
Static Public Member Functions inherited from AcceleratorBufferBase
static std::recursive_mutex &	GetMutex ()
	Get the mutex for m_objectList.
static const std::set< AcceleratorBufferBase * > &	GetObjects ()
	Get the set of all objects. You must hold a lock on m_objectListMutex while working with it.
Static Protected Attributes inherited from AcceleratorBufferBase
static std::recursive_mutex	m_objectListMutex
	Mutex controlling access to m_objectList.
static std::set< AcceleratorBufferBase * >	m_objectList
	Set of all existing AcceleratorBufferBase objects.

Detailed Description

template<class T>
class AcceleratorBuffer< T >

A buffer of memory which may be used by GPU acceleration.

At any given point in time the buffer may exist as a single copy on the CPU, a single copy on the GPU, or mirrored buffers on both sides.

Hints can be provided to the buffer about future usage patterns to optimize storage location for best performance.

This buffer generally provides std::vector semantics, but does not initialize memory or call constructors on elements when calling resize() or reserve() unless the element type is not trivially copyable. All locations not explicitly written to have undefined values. Most notably, allocated buffer space between size() and capacity() is undefined and its value may not be coherent between CPU and GPU view of the buffer.

If the element type is not trivially copyable, the data cannot be shared with the GPU. This class still supports non-trivially-copyable types as a convenience for working with waveforms on the CPU.

Member Function Documentation

__attribute__()

template<class T >

AcceleratorBuffer< T >::__attribute__

(

(noinline)

)

const &

Copies our content from another AcceleratorBuffer.

TODO perf counters

BeginHostDeviceTransferIfNeeded()

template<class T >

bool AcceleratorBuffer< T >::BeginHostDeviceTransferIfNeeded ( )

inline

Starts a host-to-device transfer if we need to do one.

Returns

true if transfer has started, false if not required

GetBuffer()

template<class T >

vk::Buffer AcceleratorBuffer< T >::GetBuffer ( )

inline

Returns the preferred buffer for GPU-side access.

This is the GPU buffer if we have one, otherwise the CPU buffer.

GetElementSize()

template<class T >

virtual size_t AcceleratorBuffer< T >::GetElementSize ( ) const

inlinevirtual

Gets the size of each entry in the container.

Implements AcceleratorBufferBase.

GetType()

template<class T >

virtual std::string AcceleratorBuffer< T >::GetType ( ) const

inlinevirtual

Gets the underlying C++ object type.

Implements AcceleratorBufferBase.

resize()

template<class T >

void AcceleratorBuffer< T >::resize ( size_t  size, bool  exactSize = false  )

inline

Change the usable size of the container.

Parameters

size	New size
exactSize	True if we want to allocate exactly the requested size rather than rounding up

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

• lib/scopehal/AcceleratorBuffer.h