EDF Scheduler

This group contains the EDF Scheduler implementation. More...

Files
file	scheduleredf.h
	This header file provides interfaces of the EDF Scheduler which are used by the implementation and the Application Configuration.
file	scheduleredfimpl.h
	This header file provides interfaces of the EDF Scheduler which are only used by the implementation.
file	scheduleredf.c
	This source file contains the implementation of _Scheduler_EDF_Initialize().
file	scheduleredfblock.c
	This source file contains the implementation of _Scheduler_EDF_Block().
file	scheduleredfchangepriority.c
	This source file contains the implementation of _Scheduler_EDF_Update_priority().
file	scheduleredfnodeinit.c
	This source file contains the implementation of _Scheduler_EDF_Node_initialize().
file	scheduleredfreleasejob.c
	This source file contains the implementation of _Scheduler_EDF_Map_priority(), _Scheduler_EDF_Unmap_priority(), _Scheduler_EDF_Release_job(), and _Scheduler_EDF_Cancel_job().
file	scheduleredfschedule.c
	This source file contains the implementation of _Scheduler_EDF_Schedule().
file	scheduleredfunblock.c
	This source file contains the implementation of _Scheduler_EDF_Unblock().
file	scheduleredfyield.c
	This source file contains the implementation of _Scheduler_EDF_Yield().

Data Structures
struct	Scheduler_EDF_Context
struct	Scheduler_EDF_Node
	Scheduler node specialization for EDF schedulers. More...

Macros
#define	SCHEDULER_EDF_MAXIMUM_PRIORITY   INT_MAX
#define	SCHEDULER_EDF_ENTRY_POINTS
#define	SCHEDULER_EDF_PRIO_MSB   0x8000000000000000

Functions
void	_Scheduler_EDF_Initialize (const Scheduler_Control *scheduler)
	Initializes EDF scheduler.
void	_Scheduler_EDF_Block (const Scheduler_Control *scheduler, Thread_Control *the_thread, Scheduler_Node *node)
	Removes the blocking thread from the ready queue and schedules is only again if the thread is executing or the heir thread.
void	_Scheduler_EDF_Schedule (const Scheduler_Control *scheduler, Thread_Control *the_thread)
	Sets the heir thread to be the next ready thread in the rbtree ready queue.
void	_Scheduler_EDF_Node_initialize (const Scheduler_Control *scheduler, Scheduler_Node *node, Thread_Control *the_thread, Priority_Control priority)
	Initializes an EDF specific scheduler node of the_thread.
void	_Scheduler_EDF_Unblock (const Scheduler_Control *scheduler, Thread_Control *the_thread, Scheduler_Node *node)
	Performs an unblocking of the thread.
void	_Scheduler_EDF_Update_priority (const Scheduler_Control *scheduler, Thread_Control *the_thread, Scheduler_Node *node)
	Updates the priority of the scheduler node.
Priority_Control	_Scheduler_EDF_Map_priority (const Scheduler_Control *scheduler, Priority_Control priority)
	Gets the mapped priority map of the priority control.
Priority_Control	_Scheduler_EDF_Unmap_priority (const Scheduler_Control *scheduler, Priority_Control priority)
	Gets the unmapped priority map of the priority control.
void	_Scheduler_EDF_Yield (const Scheduler_Control *scheduler, Thread_Control *the_thread, Scheduler_Node *node)
	Executes a thread yield for the thread.
void	_Scheduler_EDF_Release_job (const Scheduler_Control *scheduler, Thread_Control *the_thread, Priority_Node *priority_node, uint64_t deadline, Thread_queue_Context *queue_context)
	Releases a EDF job.
void	_Scheduler_EDF_Cancel_job (const Scheduler_Control *scheduler, Thread_Control *the_thread, Priority_Node *priority_node, Thread_queue_Context *queue_context)
	Cancels a job and removes the thread from the queue context.

Detailed Description

This group contains the EDF Scheduler implementation.

Macro Definition Documentation

SCHEDULER_EDF_ENTRY_POINTS

#define SCHEDULER_EDF_ENTRY_POINTS

Value:

  { \
    _Scheduler_EDF_Initialize,       /* initialize entry point */ \
    _Scheduler_EDF_Schedule,         /* schedule entry point */ \
    _Scheduler_EDF_Yield,            /* yield entry point */ \
    _Scheduler_EDF_Block,            /* block entry point */ \
    _Scheduler_EDF_Unblock,          /* unblock entry point */ \
    _Scheduler_EDF_Update_priority,  /* update priority entry point */ \
    _Scheduler_EDF_Map_priority,     /* map priority entry point */ \
    _Scheduler_EDF_Unmap_priority,   /* unmap priority entry point */ \
    SCHEDULER_DEFAULT_SMP_OPERATIONS \
    _Scheduler_EDF_Node_initialize,  /* node initialize entry point */ \
    _Scheduler_default_Node_destroy, /* node destroy entry point */ \
    _Scheduler_EDF_Release_job,      /* new period of task */ \
    _Scheduler_EDF_Cancel_job,       /* cancel period of task */ \
    _Scheduler_default_Start_idle    /* start idle entry point */ \
    SCHEDULER_DEFAULT_SET_AFFINITY_OPERATION \
  }

Entry points for the Earliest Deadline First Scheduler.

SCHEDULER_EDF_PRIO_MSB

#define SCHEDULER_EDF_PRIO_MSB   0x8000000000000000

This is just a most significant bit of Priority_Control type. It distinguishes threads which are deadline driven (priority represented by a lower number than SCHEDULER_EDF_PRIO_MSB) from those ones who do not have any deadlines and thus are considered background tasks.

Function Documentation

_Scheduler_EDF_Block()

void _Scheduler_EDF_Block	(	const Scheduler_Control *	scheduler,
		Thread_Control *	the_thread,
		Scheduler_Node *	node
	)

Removes the blocking thread from the ready queue and schedules is only again if the thread is executing or the heir thread.

Parameters

[in,out]	scheduler	The scheduler for the operation.
	the_thread	The thread to operate upon.
[in,out]	node	The scheduler node for this thread.

_Scheduler_EDF_Cancel_job()

void _Scheduler_EDF_Cancel_job	(	const Scheduler_Control *	scheduler,
		Thread_Control *	the_thread,
		Priority_Node *	priority_node,
		Thread_queue_Context *	queue_context
	)

Cancels a job and removes the thread from the queue context.

Parameters

	scheduler	The scheduler instance.
	the_thread	The thread for the operation.
[in,out]	priority_node	The corresponding priority node.
[in,out]	queue_context	The thread queue context.

_Scheduler_EDF_Initialize()

void _Scheduler_EDF_Initialize

(

const Scheduler_Control *

scheduler

)

Initializes EDF scheduler.

This routine initializes the EDF scheduler.

Parameters

[in,out]

scheduler

The scheduler instance.

_Scheduler_EDF_Map_priority()

Priority_Control _Scheduler_EDF_Map_priority	(	const Scheduler_Control *	scheduler,
		Priority_Control	priority
	)

Gets the mapped priority map of the priority control.

Parameters

scheduler	Not used in this operation.
priority	The priority control to get the priority map of.

Returns

The mapped priority map of priority.

_Scheduler_EDF_Node_initialize()

void _Scheduler_EDF_Node_initialize	(	const Scheduler_Control *	scheduler,
		Scheduler_Node *	node,
		Thread_Control *	the_thread,
		Priority_Control	priority
	)

Initializes an EDF specific scheduler node of the_thread.

Parameters

scheduler	The scheduler instance.
node	The node being initialized.
the_thread	The thread of the node.
priority	The thread priority.

_Scheduler_EDF_Release_job()

void _Scheduler_EDF_Release_job	(	const Scheduler_Control *	scheduler,
		Thread_Control *	the_thread,
		Priority_Node *	priority_node,
		uint64_t	deadline,
		Thread_queue_Context *	queue_context
	)

Releases a EDF job.

Parameters

	scheduler	The scheduler instance
	the_thread	The thread
[in,out]	priority_node	The priority node for the operation.
	deadline	The deadline for the job.
[in,out]	queue_context	The thread queue context.

_Scheduler_EDF_Schedule()

void _Scheduler_EDF_Schedule	(	const Scheduler_Control *	scheduler,
		Thread_Control *	the_thread
	)

Sets the heir thread to be the next ready thread in the rbtree ready queue.

This kernel routine sets the heir thread to be the next ready thread in the rbtree ready queue.

Parameters

[in,out]	scheduler	The scheduler instance.
	the_thread	The thread being scheduled.

_Scheduler_EDF_Unblock()

void _Scheduler_EDF_Unblock	(	const Scheduler_Control *	scheduler,
		Thread_Control *	the_thread,
		Scheduler_Node *	node
	)

Performs an unblocking of the thread.

Parameters

[in,out]	scheduler	The scheduler instance.
	the_thread	The unblocking thread. May be set as new heir.
[in,out]	node	The scheduler node for the thread.

_Scheduler_EDF_Unmap_priority()

Priority_Control _Scheduler_EDF_Unmap_priority	(	const Scheduler_Control *	scheduler,
		Priority_Control	priority
	)

Gets the unmapped priority map of the priority control.

Parameters

scheduler	Not used in this operation.
priority	The priority control to get the priority map of.

Returns

The unmapped priority map of priority.

_Scheduler_EDF_Update_priority()

void _Scheduler_EDF_Update_priority	(	const Scheduler_Control *	scheduler,
		Thread_Control *	the_thread,
		Scheduler_Node *	node
	)

Updates the priority of the scheduler node.

Parameters

	scheduler	The scheduler instance.
	the_thread	The thread for the operation.
[in,out]	node	The priority node to update the priority of.

_Scheduler_EDF_Yield()

void _Scheduler_EDF_Yield	(	const Scheduler_Control *	scheduler,
		Thread_Control *	the_thread,
		Scheduler_Node *	node
	)

Executes a thread yield for the thread.

Parameters

[in,out]	scheduler	The scheduler instance.
	the_thread	The thread that performs the yield.
[in,out]	node	The scheduler node for this thread.