Base class for virtual memory allocators. More...

#include <base_alloc.h>

Inheritance diagram for virtmem::BaseVAlloc:

Public Member Functions
void	start (void)
	Starts the allocator. More...

void	stop (void)
	Deinitializes the allocator. More...

void	setPoolSize (VPtrSize ps)
	Sets the total size of the memory pool. More...

VPtrNum	allocRaw (VPtrSize size)
	Allocates a piece of raw (virtual) memory. More...

void	freeRaw (VPtrNum ptr)
	Frees a memory block for re-usage. More...

void *	read (VPtrNum p, VPtrSize size)
	Reads a raw block of (virtual) memory. More...

void	write (VPtrNum p, const void *d, VPtrSize size)
	Writes a piece of raw data to (virtual) memory. More...

void	flush (void)
	Synchronizes all big memory pages. More...

void	clearPages (void)
	Synchronizes and clears all big memory pages. More...

uint8_t	getFreeBigPages (void) const

uint8_t	getUnlockedSmallPages (void) const
	Returns amount of small pages which are not locked.

uint8_t	getUnlockedMediumPages (void) const
	Returns amount of medium pages which are not locked.

uint8_t	getUnlockedBigPages (void) const
	Returns amount of big pages which are not locked.

uint8_t	getSmallPageCount (void) const
	Returns total amount of small pages.

uint8_t	getMediumPageCount (void) const
	Returns total amount of medium pages.

uint8_t	getBigPageCount (void) const
	Returns total amount of big pages.

VirtPageSize	getSmallPageSize (void) const
	Returns the size of a small page.

VirtPageSize	getMediumPageSize (void) const
	Returns the size of a medium page.

VirtPageSize	getBigPageSize (void) const
	Returns the size of a big page.

VPtrSize	getPoolSize (void) const
	Returns the size the memory pool. More...

Statistics functions.
The following functions are only available when VIRTMEM_TRACE_STATS is defined (in config.h).
VPtrSize	getMemUsed (void) const
	Returns total memory used.

VPtrSize	getMaxMemUsed (void) const
	Returns the maximum memory used so far.

uint32_t	getBigPageReads (void) const
	Returns the times big pages were read (swapped).

uint32_t	getBigPageWrites (void) const
	Returns the times big pages written (synchronized).

uint32_t	getBytesRead (void) const
	Returns the amount of bytes read as a result of page swaps.

uint32_t	getBytesWritten (void) const
	Returns the amount of bytes written as a results of page swaps.

void	resetStats (void)
	Reset all statistics. Called by start()

Protected Member Functions
void	writeZeros (VPtrNum start, VPtrSize n)
	Writes zeros to raw virtual memory. Can be used to initialize the memory pool. More...

Pure virtual functions
The following functions should be defined by derived allocator classes.
virtual void	doStart (void)=0

virtual void	doStop (void)=0

virtual void	doRead (void *data, VPtrSize offset, VPtrSize size)=0

virtual void	doWrite (const void *data, VPtrSize offset, VPtrSize size)=0

Detailed Description

Base class for virtual memory allocators.

This class defines methods to (de)initialize the allocator (see start() and stop()). In addition, this class can be used for 'raw' memory access.

Member Function Documentation

VPtrNum virtmem::BaseVAlloc::allocRaw ( VPtrSize size )

Allocates a piece of raw (virtual) memory.

Parameters

size	the size of the memory block

Returns: The starting address of the memory block. Will return zero if out of memory.

void virtmem::BaseVAlloc::clearPages ( void )

Synchronizes and clears all big memory pages.

Note: This function is merely used for debugging.

void virtmem::BaseVAlloc::flush ( void )

Synchronizes all big memory pages.

Note: This function is merely used for debugging.

void virtmem::BaseVAlloc::freeRaw ( VPtrNum ptr )

Frees a memory block for re-usage.

Parameters

ptr	starting address of the memory block. This function will do nothing if ptr is zero.

uint8_t virtmem::BaseVAlloc::getFreeBigPages ( void ) const

Returns: number of big pages that are not used and are not locked.

VPtrSize virtmem::BaseVAlloc::getPoolSize ( void ) const

inline

Returns the size the memory pool.

Note: Some memory is used for bookkeeping, therefore, the amount returned by this function does not equate the amount that can be allocated.

void * virtmem::BaseVAlloc::read	(	VPtrNum	p,
		VPtrSize	size
	)

Reads a raw block of (virtual) memory.

Parameters

p	starting address of memory block
size	number of bytes to read

Returns: a pointer to a memory block (a memory page) containing the data

Note: The memory block returned by this function is temporary and may be invalidated during a page swap. To use the memory accross reads and writes it should be locked.

void virtmem::BaseVAlloc::setPoolSize ( VPtrSize ps )

inline

Sets the total size of the memory pool.

Parameters

ps	size of the memory pool.

Note: The poolsize can also be set via the constructor of most allocators.; This function is unavailable for MultiSPIRAMVAllocP and StaticVAlloc.; This function should always called before start().

void virtmem::BaseVAlloc::start ( void )

Starts the allocator.

This function should always be called during initialization, i.e. in setup() function of your sketch. If the allocator was stopped (see stop()), this function should be called again before using the allocator. All used virtual memory (if any) will be cleared during initialization.

Examples:: multispiram_simple.ino.

void virtmem::BaseVAlloc::stop ( void )

Deinitializes the allocator.

Run start() before using the allocator to re-initialize it.

void virtmem::BaseVAlloc::write	(	VPtrNum	p,
		const void *	d,
		VPtrSize	size
	)

Writes a piece of raw data to (virtual) memory.

Parameters

p	starting address of the virtual memory block
d	pointer to data to be written
size	number of bytes to write

void virtmem::BaseVAlloc::writeZeros	(	VPtrNum	start,
		VPtrSize	n
	)

protected

Writes zeros to raw virtual memory. Can be used to initialize the memory pool.

Parameters

start	Start address
n	Amount of bytes (zeros) to write

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

virtmem/src/internal/base_alloc.h
virtmem/src/base_alloc.cpp

Public Member Functions

Protected Member Functions

Detailed Description

Member Function Documentation