contur::DeadlockDetector Class Reference

Deadlock detection/prevention helper. More...

#include <deadlock_detector.h>

Public Member Functions
	DeadlockDetector ()
	Constructs deadlock detector with empty graphs.
	~DeadlockDetector ()
	Destroys deadlock detector.
	DeadlockDetector (const DeadlockDetector &)=delete
	Copy construction is disabled.
DeadlockDetector &	operator= (const DeadlockDetector &)=delete
	Copy assignment is disabled.
	DeadlockDetector (DeadlockDetector &&) noexcept
	Move-constructs detector state.
DeadlockDetector &	operator= (DeadlockDetector &&) noexcept
	Move-assigns detector state.
void	onAcquire (ProcessId pid, ResourceId resource)
	Records successful acquisition of a resource by a process.
void	onAcquire (ProcessId pid, ResourceId resource, ThreadToken threadToken)
	Thread-aware variant of resource acquisition tracking.
void	onRelease (ProcessId pid, ResourceId resource)
	Records release of a resource by a process.
void	onRelease (ProcessId pid, ResourceId resource, ThreadToken threadToken)
	Thread-aware variant of resource release tracking.
void	onWait (ProcessId pid, ResourceId resource)
	Records waiting on a resource and updates wait-for graph.
void	onWait (ProcessId pid, ResourceId resource, ThreadToken threadToken)
	Thread-aware variant of wait edge tracking.
bool	hasDeadlock () const
	Returns true if the current wait-for graph has a cycle.
std::vector< ProcessId >	getDeadlockedProcesses () const
	Returns process IDs involved in deadlock cycles.
void	onInternalLockAcquire (ThreadToken threadToken, ResourceId lockId)
	Records internal lock acquisition order for lock-order analysis.
void	onInternalLockRelease (ThreadToken threadToken, ResourceId lockId)
	Records internal lock release for lock-order analysis.
bool	hasInternalLockOrderCycle () const
	Returns true when internal lock-order graph contains a cycle.
std::vector< ResourceId >	getInternalLockOrderCycle () const
	Returns lock IDs involved in lock-order cycles.
bool	isSafeState (const std::vector< ResourceAllocation > &current, const std::vector< ResourceAllocation > &maximum, const std::vector< std::uint32_t > &available) const
	Banker's algorithm safety check.

Private Attributes
std::unique_ptr< Impl >	impl_

Detailed Description

Deadlock detection/prevention helper.

Maintains a wait-for graph for cycle detection and provides Banker's safety check for allocation state validation.

Definition at line 30 of file deadlock_detector.h.

Constructor & Destructor Documentation

DeadlockDetector() [1/3]

contur::DeadlockDetector::DeadlockDetector

(

)

Constructs deadlock detector with empty graphs.

Referenced by DeadlockDetector(), DeadlockDetector(), operator=(), and operator=().

~DeadlockDetector()

contur::DeadlockDetector::~DeadlockDetector

(

)

Destroys deadlock detector.

DeadlockDetector() [2/3]

contur::DeadlockDetector::DeadlockDetector ( const DeadlockDetector & )

delete

Copy construction is disabled.

References DeadlockDetector().

DeadlockDetector() [3/3]

contur::DeadlockDetector::DeadlockDetector ( DeadlockDetector && )

noexcept

Move-constructs detector state.

References DeadlockDetector().

Member Function Documentation

getDeadlockedProcesses()

std::vector< ProcessId > contur::DeadlockDetector::getDeadlockedProcesses ( ) const

nodiscard

Returns process IDs involved in deadlock cycles.

References getDeadlockedProcesses().

Referenced by getDeadlockedProcesses().

getInternalLockOrderCycle()

std::vector< ResourceId > contur::DeadlockDetector::getInternalLockOrderCycle ( ) const

nodiscard

Returns lock IDs involved in lock-order cycles.

References getInternalLockOrderCycle().

Referenced by getInternalLockOrderCycle().

hasDeadlock()

bool contur::DeadlockDetector::hasDeadlock ( ) const

nodiscard

Returns true if the current wait-for graph has a cycle.

References hasDeadlock().

Referenced by hasDeadlock().

hasInternalLockOrderCycle()

bool contur::DeadlockDetector::hasInternalLockOrderCycle ( ) const

nodiscard

Returns true when internal lock-order graph contains a cycle.

References hasInternalLockOrderCycle().

Referenced by hasInternalLockOrderCycle().

isSafeState()

bool contur::DeadlockDetector::isSafeState ( const std::vector< ResourceAllocation > & current, const std::vector< ResourceAllocation > & maximum, const std::vector< std::uint32_t > & available ) const

nodiscard

Banker's algorithm safety check.

current[i].resources[r] is currently allocated count for process i, resource r. maximum[i].resources[r] is maximum demand for process i, resource r. available[r] is currently available count for resource r.

Parameters

current	Currently allocated resources per process.
maximum	Maximum claims per process.
available	Currently available resource vector.

Returns

True when the state is safe; false otherwise.

References isSafeState().

Referenced by isSafeState().

onAcquire() [1/2]

void contur::DeadlockDetector::onAcquire	(	ProcessId	pid,
		ResourceId	resource )

Records successful acquisition of a resource by a process.

Parameters

pid	Process that acquired resource.
resource	Acquired resource identifier.

References onAcquire().

Referenced by onAcquire(), and onAcquire().

onAcquire() [2/2]

void contur::DeadlockDetector::onAcquire	(	ProcessId	pid,
		ResourceId	resource,
		ThreadToken	threadToken )

Thread-aware variant of resource acquisition tracking.

References onAcquire().

onInternalLockAcquire()

void contur::DeadlockDetector::onInternalLockAcquire	(	ThreadToken	threadToken,
		ResourceId	lockId )

Records internal lock acquisition order for lock-order analysis.

References onInternalLockAcquire().

Referenced by onInternalLockAcquire().

onInternalLockRelease()

void contur::DeadlockDetector::onInternalLockRelease	(	ThreadToken	threadToken,
		ResourceId	lockId )

Records internal lock release for lock-order analysis.

References onInternalLockRelease().

Referenced by onInternalLockRelease().

onRelease() [1/2]

void contur::DeadlockDetector::onRelease	(	ProcessId	pid,
		ResourceId	resource )

Records release of a resource by a process.

Parameters

pid	Process that released resource.
resource	Released resource identifier.

References onRelease().

Referenced by onRelease(), and onRelease().

onRelease() [2/2]

void contur::DeadlockDetector::onRelease	(	ProcessId	pid,
		ResourceId	resource,
		ThreadToken	threadToken )

Thread-aware variant of resource release tracking.

References onRelease().

onWait() [1/2]

void contur::DeadlockDetector::onWait	(	ProcessId	pid,
		ResourceId	resource )

Records waiting on a resource and updates wait-for graph.

Parameters

pid	Waiting process.
resource	Requested resource identifier.

References onWait().

Referenced by onWait(), and onWait().

onWait() [2/2]

void contur::DeadlockDetector::onWait	(	ProcessId	pid,
		ResourceId	resource,
		ThreadToken	threadToken )

Thread-aware variant of wait edge tracking.

References onWait().

operator=() [1/2]

DeadlockDetector & contur::DeadlockDetector::operator= ( const DeadlockDetector & )

delete

Copy assignment is disabled.

References DeadlockDetector().

operator=() [2/2]

DeadlockDetector & contur::DeadlockDetector::operator= ( DeadlockDetector && )

noexcept

Move-assigns detector state.

References DeadlockDetector().

Member Data Documentation

impl_

std::unique_ptr<Impl> contur::DeadlockDetector::impl_

private

Definition at line 109 of file deadlock_detector.h.

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

• include/contur/sync/deadlock_detector.h