Semaphore Handler. More...

Files
file	coresem.h
	Data Associated with the Counting Semaphore Handler.

file	coresemimpl.h
	Inlined Routines Associated with the SuperCore Semaphore.

file	semaphoreimpl.h
	Semaphore Implementation.

file	coresem.c
	Core Semaphore Initialize.

Classes
struct	CORE_semaphore_Control

struct	Sem_Control

Macros
#define	SEMAPHORE_TQ_OPERATIONS &_Thread_queue_Operations_priority

Functions
void	_CORE_semaphore_Initialize (CORE_semaphore_Control *the_semaphore, uint32_t initial_value)
	Initializes the semaphore based on the parameters passed. More...

static __inline__ void	_CORE_semaphore_Acquire_critical (CORE_semaphore_Control the_semaphore, Thread_queue_Context queue_context)
	Acquires the semaphore critical. More...

static __inline__ void	_CORE_semaphore_Release (CORE_semaphore_Control the_semaphore, Thread_queue_Context queue_context)
	Releases the semaphore. More...

static __inline__ void	_CORE_semaphore_Destroy (CORE_semaphore_Control the_semaphore, const Thread_queue_Operations operations, Thread_queue_Context *queue_context)
	Destroys the semaphore. More...

static __inline__ Status_Control	_CORE_semaphore_Surrender (CORE_semaphore_Control the_semaphore, const Thread_queue_Operations operations, uint32_t maximum_count, Thread_queue_Context *queue_context)
	Surrenders a unit to the semaphore. More...

static __inline__ uint32_t	_CORE_semaphore_Get_count (const CORE_semaphore_Control *the_semaphore)
	Returns the current count associated with the semaphore. More...

static __inline__ Status_Control	_CORE_semaphore_Seize (CORE_semaphore_Control the_semaphore, const Thread_queue_Operations operations, Thread_Control executing, bool wait, Thread_queue_Context queue_context)
	Seizes the semaphore. More...

static Sem_Control *	_Sem_Get (struct _Semaphore_Control *_sem)
	Gets the Sem_Control * of the semaphore. More...

static Thread_Control *	_Sem_Queue_acquire_critical (Sem_Control sem, Thread_queue_Context queue_context)
	Acquires the semaphore queue critical. More...

static void	_Sem_Queue_release (Sem_Control sem, ISR_Level level, Thread_queue_Context queue_context)
	Releases the semaphore queue. More...

Detailed Description

Semaphore Handler.

This handler encapsulates functionality which provides the foundation Semaphore services used in all of the APIs supported by RTEMS.

Function Documentation

◆ _CORE_semaphore_Acquire_critical()

static __inline__ void _CORE_semaphore_Acquire_critical	(	CORE_semaphore_Control *	the_semaphore,
		Thread_queue_Context *	queue_context
	)

static

Acquires the semaphore critical.

This routine acquires the semaphore.

Parameters

[in,out]	the_semaphore	The semaphore to acquire.
	queue_context	The thread queue context.

Definition at line 67 of file coresemimpl.h.

◆ _CORE_semaphore_Destroy()

static __inline__ void _CORE_semaphore_Destroy	(	CORE_semaphore_Control *	the_semaphore,
		const Thread_queue_Operations *	operations,
		Thread_queue_Context *	queue_context
	)

static

Destroys the semaphore.

This routine destroys the semaphore.

Parameters

[out]	the_semaphore	The semaphore to destroy.
	operations	The thread queue operations.
	queue_context	The thread queue context.

Definition at line 100 of file coresemimpl.h.

◆ _CORE_semaphore_Get_count()

static __inline__ uint32_t _CORE_semaphore_Get_count ( const CORE_semaphore_Control * the_semaphore )

static

Returns the current count associated with the semaphore.

Parameters

the_semaphore The semaphore to obtain the count of.

Returns: the current count of this semaphore.

Definition at line 175 of file coresemimpl.h.

◆ _CORE_semaphore_Initialize()

void _CORE_semaphore_Initialize	(	CORE_semaphore_Control *	the_semaphore,
		uint32_t	initial_value
	)

Initializes the semaphore based on the parameters passed.

This package is the implementation of the CORE Semaphore Handler. This core object utilizes standard Dijkstra counting semaphores to provide synchronization and mutual exclusion capabilities.

This routine initializes the semaphore based on the parameters passed.

Parameters

[out]	the_semaphore	The semaphore to initialize.
	initial_value	The initial count of the semaphore.

Definition at line 23 of file coresem.c.

◆ _CORE_semaphore_Release()

static __inline__ void _CORE_semaphore_Release	(	CORE_semaphore_Control *	the_semaphore,
		Thread_queue_Context *	queue_context
	)

static

Releases the semaphore.

This routine releases the semaphore.

Parameters

[in,out]	the_semaphore	The semaphore to release.
	queue_context	The thread queue context.

Definition at line 83 of file coresemimpl.h.

◆ _CORE_semaphore_Seize()

static __inline__ Status_Control _CORE_semaphore_Seize	(	CORE_semaphore_Control *	the_semaphore,
		const Thread_queue_Operations *	operations,
		Thread_Control *	executing,
		bool	wait,
		Thread_queue_Context *	queue_context
	)

static

Seizes the semaphore.

This routine attempts to receive a unit from the_semaphore. If a unit is available or if the wait flag is false, then the routine returns. Otherwise, the calling task is blocked until a unit becomes available.

Parameters

[in,out]	the_semaphore	The semaphore to obtain.
	operations	The thread queue operations.
	executing	The currently executing thread.
	wait	Indicates whether the calling thread is willing to wait.
	queue_context	is a temporary variable used to contain the ISR disable level cookie.

Return values

STATUS_SUCCESSFUL	The semaphore was successfully seized.
STATUS_UNSATISFIED	The semaphore is currently not free and the calling thread not willing to wait.
STATUS_TIMEOUT	A timeout occured.

Definition at line 202 of file coresemimpl.h.

◆ _CORE_semaphore_Surrender()

static __inline__ Status_Control _CORE_semaphore_Surrender	(	CORE_semaphore_Control *	the_semaphore,
		const Thread_queue_Operations *	operations,
		uint32_t	maximum_count,
		Thread_queue_Context *	queue_context
	)

static

Surrenders a unit to the semaphore.

This routine frees a unit to the semaphore. If a task was blocked waiting for a unit from this semaphore, then that task will be readied and the unit given to that task. Otherwise, the unit will be returned to the semaphore.

Parameters

[in,out]	the_semaphore	is the semaphore to surrender
	operations	The thread queue operations.
	maximum_count	The maximum number of units in the semaphore.
	queue_context	is a temporary variable used to contain the ISR disable level cookie.

Return values

STATUS_SUCCESSFUL	The unit was successfully freed to the semaphore.
STATUS_MAXIMUM_COUNT_EXCEEDED	The maximum number of units was exceeded.

Definition at line 131 of file coresemimpl.h.

◆ _Sem_Get()

static Sem_Control* _Sem_Get ( struct _Semaphore_Control * _sem )

inlinestatic

Gets the Sem_Control * of the semaphore.

Parameters

sem	The Semaphore_Control * to cast to Sem_Control *.

Returns: sem cast to Sem_Control *.

Definition at line 55 of file semaphoreimpl.h.

◆ _Sem_Queue_acquire_critical()

static Thread_Control* _Sem_Queue_acquire_critical	(	Sem_Control *	sem,
		Thread_queue_Context *	queue_context
	)

inlinestatic

Acquires the semaphore queue critical.

This routine acquires the semaphore.

Parameters

[in,out]	sem	The semaphore to acquire the queue of.
	queue_context	The thread queue context.

Returns: The executing thread.

Definition at line 70 of file semaphoreimpl.h.

◆ _Sem_Queue_release()

static void _Sem_Queue_release	(	Sem_Control *	sem,
		ISR_Level	level,
		Thread_queue_Context *	queue_context
	)

inlinestatic

Releases the semaphore queue.

Parameters

[in,out]	sem	The semaphore to release the queue of.
	level	The interrupt level value to restore the interrupt status on the processor.
	queue_context	The thread queue context.

Definition at line 94 of file semaphoreimpl.h.

Files

Classes

Macros

Functions

Detailed Description

Function Documentation

◆ _CORE_semaphore_Acquire_critical()

◆ _CORE_semaphore_Destroy()

◆ _CORE_semaphore_Get_count()

◆ _CORE_semaphore_Initialize()

◆ _CORE_semaphore_Release()

◆ _CORE_semaphore_Seize()

◆ _CORE_semaphore_Surrender()

◆ _Sem_Get()

◆ _Sem_Queue_acquire_critical()

◆ _Sem_Queue_release()