Classes
class	DescriptorPool
	Defines a pool of descriptor objects which is used to allocate descriptors and to store them while they are not safe to delete. More...

class	PoolElement
	This class is used to hold the memory management information (Header) and a descriptor object. More...

class	PoolManager
	A manager class for the reference count protected memory pools. More...

class	ReadFirstOp
	Class used for placement in the Op Table to complete an operation that failed to complete in a bounded number of steps. More...

Functions
template<typename DescrType , typename... Args >
DescrType *	get_descriptor (Args &&...args)
	Constructs and returns a descriptor. More...

void	free_descriptor (tervel::util::Descriptor *descr, bool dont_check=false)
	Once a user is done with a descriptor, they should free it with this method. More...

bool	is_watched (tervel::util::Descriptor *descr)
	This method is used to determine if the passed descriptor is under rc protection. More...

bool	watch (tervel::util::Descriptor descr, std::atomic< void > address, void value)
	This method is used to increment the reference count of the passed descriptor object. More...

void	unwatch (tervel::util::Descriptor *descr)
	This method is used to decrement the reference count of the passed descriptor object. More...

void *	mark_first (tervel::util::Descriptor *descr)
	This returns the passed reference with its least signifcant bit set to 1. More...

void	atomic_mark_first (std::atomic< void * > *address)
	This function atomically bit marks the value at address. More...

tervel::util::Descriptor *	unmark_first (void *descr)
	This returns an unbitmarked reference. More...

bool	is_descriptor_first (void *descr)
	This returns whether or not the least significant bit holds a bitmark. More...

void *	remove_descriptor (void expected, std::atomic< void > *address)
	This method is used to remove a descriptor object that is conflict with another threads operation. More...

void *	descriptor_read_first (std::atomic< void * > *address)
	This function determines the logical value of an address which may have either a RC descriptor or a normal value. More...

PoolElement *	get_elem_from_descriptor (tervel::util::Descriptor *descr)
	If the given descriptor was allocated through a DescriptorPool, then it has an associated PoolElement header. More...

Variables
const long	DEBUG_EXPECTED_STAMP = 0xDEADBEEF

Function Documentation

void tervel::util::memory::rc::atomic_mark_first ( std::atomic< void * > * address )

inline

This function atomically bit marks the value at address.

This function atomically bit marks the value at address

Parameters

address the address to bitmark

void* tervel::util::memory::rc::descriptor_read_first ( std::atomic< void * > * address )

inline

This function determines the logical value of an address which may have either a RC descriptor or a normal value.

Parameters

address to read

Returns: the current logical value

void tervel::util::memory::rc::free_descriptor	(	tervel::util::Descriptor *	descr,
		bool	dont_check = `false`
	)

inline

Once a user is done with a descriptor, they should free it with this method.

Parameters

descr	The descriptor to free.
dont_check	Don't check if the descriptor is being watched before freeing it. Use this flag if you know that no other thread has had access to this descriptor.
pool	the pool to use when freeing the descriptor.

template<typename DescrType , typename... Args >

DescrType* tervel::util::memory::rc::get_descriptor ( Args &&... args )

inline

Constructs and returns a descriptor.

Arguments are forwarded to the constructor of the given descriptor type. User should call free_descriptor on the returned pointer when they are done with it to avoid memory leaks.

PoolElement * tervel::util::memory::rc::get_elem_from_descriptor ( tervel::util::Descriptor * descr )

inline

If the given descriptor was allocated through a DescriptorPool, then it has an associated PoolElement header.

This methods returns that PoolElement.

Use with caution as Descriptors not allocated from a pool will not have an associated header, and, thus, the returned value will be to some random place in memory.

Parameters

descr The Descriptor pointer allocated through a descriptor pool which thus has an associated PoolElement.

Returns: The associated PoolElement.

bool tervel::util::memory::rc::is_descriptor_first ( void * descr )

inline

This returns whether or not the least significant bit holds a bitmark.

Parameters

the	reference to check

Returns: whether or not it holds a bitmark

bool tervel::util::memory::rc::is_watched ( tervel::util::Descriptor * descr )

inline

This method is used to determine if the passed descriptor is under rc protection.

Internally calls on_is_watched

Parameters

descr the descriptor to be checked for rc protection.

void* tervel::util::memory::rc::mark_first ( tervel::util::Descriptor * descr )

inline

This returns the passed reference with its least signifcant bit set to 1.

Parameters

descr the reference to bitmark

Returns: the bitmarked reference

void* tervel::util::memory::rc::remove_descriptor	(	void *	expected,
		std::atomic< void * > *	address
	)

inline

This method is used to remove a descriptor object that is conflict with another threads operation.

It first checks the recursive depth before proceeding. Next it protects against the object being reused else where by acquiring either HP or RC watch on the object. Then once it is safe it will call the objects complete function This function must guarantee that after its return the object has been removed It returns the value.

Parameters

expected	a marked reference to the object
address	the location expected was read from dereferenced from.

Returns: the current value of the address

tervel::util::Descriptor* tervel::util::memory::rc::unmark_first ( void * descr )

inline

This returns an unbitmarked reference.

Parameters

the	reference to remove the bitmark from

Returns: the unbitmarked reference

void tervel::util::memory::rc::unwatch ( tervel::util::Descriptor * descr )

inline

This method is used to decrement the reference count of the passed descriptor object.

Then it will call on_unwatch and decrement any related objects necessary Internally calls on_unwatch

Parameters

descr the descriptor which no longer needs rc protection.

bool tervel::util::memory::rc::watch	(	tervel::util::Descriptor *	descr,
		std::atomic< void * > *	address,
		void *	value
	)

inline

This method is used to increment the reference count of the passed descriptor object.

If after incrementing the reference count the object is still at the address (indicated by *a == value), it will call on_watch. If that returns true then it will return true. Otherwise it decrements the reference count and returns false Internally calls on_watch

Parameters

descr	the descriptor which needs rc protection
address	address it was dereferenced from
val	the read value of the address

Returns: true if successfully acquired a watch

Variable Documentation

const long tervel::util::memory::rc::DEBUG_EXPECTED_STAMP = 0xDEADBEEF

Classes

Functions

Variables

Function Documentation

Variable Documentation