Scheduling-strategy-facing interface for a kernel task slot. More...

#include <stk_common.h>

Inheritance diagram for stk::IKernelTask:

Collaboration diagram for stk::IKernelTask:

Public Types
typedef DLHeadType	ListHeadType
	List head type for IKernelTask elements.
typedef DLEntryType	ListEntryType
	List entry type of IKernelTask elements.
typedef DListEntry< IKernelTask, _ClosedLoop >	DLEntryType
	Convenience alias for this entry type. Used to avoid repeating the full template spelling.
typedef DListHead< IKernelTask, _ClosedLoop >	DLHeadType
	Convenience alias for the corresponding list head type.

Public Member Functions
virtual ITask *	GetUserTask ()=0
	Get user task.
virtual Stack *	GetUserStack ()=0
	Get pointer to the user task's stack.
virtual int32_t	GetWeight () const =0
	Get static base weight assigned to the task.
virtual void	SetCurrentWeight (int32_t weight)=0
	Set the current dynamic weight value used by the scheduling strategy.
virtual int32_t	GetCurrentWeight () const =0
	Get the current dynamic weight value of this task.
virtual Timeout	GetHrtPeriodicity () const =0
	Get HRT task execution periodicity.
virtual Timeout	GetHrtDeadline () const =0
	Get HRT task deadline (max allowed task execution time).
virtual Timeout	GetHrtRelativeDeadline () const =0
	Get HRT task's relative deadline.
virtual bool	IsSleeping () const =0
	Check whether the task is currently sleeping.
virtual void	Wake ()=0
	Wake a sleeping task on the next scheduling tick.
DLHeadType *	GetHead () const
	Get the list head this entry currently belongs to.
DLEntryType *	GetNext () const
	Get the next entry in the list.
DLEntryType *	GetPrev () const
	Get the previous entry in the list.
bool	IsLinked () const
	Check whether this entry is currently a member of any list.
	operator IKernelTask * ()
	Implicit conversion to a mutable pointer to the host object (T).
	operator const IKernelTask * () const
	Implicit conversion to a const pointer to the host object (T).

Private Member Functions
void	Link (DLHeadType head, DLEntryType next, DLEntryType *prev)
	Wire this entry into a list between prev and next.
void	Unlink ()
	Remove this entry from its current list.

Private Attributes
DLHeadType *	m_head
	Owning list head, or `NULL` when the entry is not linked.
DLEntryType *	m_next
	Next entry in the list, or `NULL` (open list boundary) / first entry (closed loop).
DLEntryType *	m_prev
	Previous entry in the list, or `NULL` (open list boundary) / last entry (closed loop).

Detailed Description

Scheduling-strategy-facing interface for a kernel task slot.

Wraps a user ITask and exposes the metadata that task-switching strategy implementations (ITaskSwitchStrategy) need to make scheduling decisions: sleep state (IsSleeping, Wake), HRT timing (GetHrtPeriodicity, GetHrtDeadline, GetHrtRelativeDeadline), and weighted-round-robin support (GetWeight, GetCurrentWeight, SetCurrentWeight).

Definition at line 492 of file stk_common.h.

Member Typedef Documentation

◆ DLEntryType

typedef DListEntry<IKernelTask, _ClosedLoop> stk::util::DListEntry< IKernelTask, _ClosedLoop >::DLEntryType

inherited

Convenience alias for this entry type. Used to avoid repeating the full template spelling.

Definition at line 70 of file stk_linked_list.h.

◆ DLHeadType

typedef DListHead<IKernelTask, _ClosedLoop> stk::util::DListEntry< IKernelTask, _ClosedLoop >::DLHeadType

inherited

Convenience alias for the corresponding list head type.

Definition at line 75 of file stk_linked_list.h.

◆ ListEntryType

typedef DLEntryType stk::IKernelTask::ListEntryType

List entry type of IKernelTask elements.

Definition at line 503 of file stk_common.h.

◆ ListHeadType

typedef DLHeadType stk::IKernelTask::ListHeadType

List head type for IKernelTask elements.

Definition at line 498 of file stk_common.h.

Member Function Documentation

◆ GetCurrentWeight()

virtual int32_t stk::IKernelTask::GetCurrentWeight ( ) const

pure virtual

Get the current dynamic weight value of this task.

Returns: Current dynamic weight value.

See also: SwitchStrategySmoothWeightedRoundRobin

Note: Weight API

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::SwitchStrategySmoothWeightedRoundRobin::GetNext().

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◆ GetHead()

DLHeadType * stk::util::DListEntry< IKernelTask, _ClosedLoop >::GetHead ( ) const

inlineinherited

Get the list head this entry currently belongs to.

Returns: Pointer to the owning DListHead, or NULL if the entry is not linked.

Definition at line 80 of file stk_linked_list.h.

80{ return m_head; }

stk::util::DListEntry

Intrusive doubly-linked list node. Embed this as a base class in any object (T) that needs to partici...

Definition stk_linked_list.h:58

◆ GetHrtDeadline()

virtual Timeout stk::IKernelTask::GetHrtDeadline ( ) const

pure virtual

Get HRT task deadline (max allowed task execution time).

Returns: Deadline of the task (ticks).

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::SwitchStrategyMonotonic< MSS_TYPE_RATE >::AddTask(), stk::SchedulabilityCheck::IsSchedulableWCRT(), and stk::test::TEST().

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◆ GetHrtPeriodicity()

virtual Timeout stk::IKernelTask::GetHrtPeriodicity ( ) const

pure virtual

Get HRT task execution periodicity.

Returns: Periodicity of the task (ticks).

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::SwitchStrategyMonotonic< MSS_TYPE_RATE >::AddTask(), stk::SchedulabilityCheck::IsSchedulableWCRT(), and stk::test::TEST().

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◆ GetHrtRelativeDeadline()

virtual Timeout stk::IKernelTask::GetHrtRelativeDeadline ( ) const

pure virtual

Get HRT task's relative deadline.

Returns: Relative deadline of the task (ticks).

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::SwitchStrategyEDF::GetNext(), stk::test::TEST(), and stk::test::TEST().

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◆ GetNext()

DLEntryType * stk::util::DListEntry< IKernelTask, _ClosedLoop >::GetNext ( ) const

inlineinherited

Get the next entry in the list.

Returns: Pointer to the next DListEntry, or NULL if this is the last entry (open list) or the first entry (closed loop, where next wraps to first).

Note: In a closed loop (_ClosedLoop == true) this pointer is never NULL when the entry is linked.

Definition at line 88 of file stk_linked_list.h.

88{ return m_next; }

◆ GetPrev()

DLEntryType * stk::util::DListEntry< IKernelTask, _ClosedLoop >::GetPrev ( ) const

inlineinherited

Get the previous entry in the list.

Returns: Pointer to the previous DListEntry, or NULL if this is the first entry (open list) or the last entry (closed loop, where prev wraps to last).

Note: In a closed loop (_ClosedLoop == true) this pointer is never NULL when the entry is linked.

Definition at line 96 of file stk_linked_list.h.

96{ return m_prev; }

◆ GetUserStack()

virtual Stack * stk::IKernelTask::GetUserStack ( )

pure virtual

Get pointer to the user task's stack.

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

◆ GetUserTask()

virtual ITask * stk::IKernelTask::GetUserTask ( )

pure virtual

Get user task.

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TEST(), stk::test::TestAlgorithm(), and stk::test::TestPriorityNext().

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◆ GetWeight()

virtual int32_t stk::IKernelTask::GetWeight ( ) const

pure virtual

Get static base weight assigned to the task.

Returns: Static weight value of the task.

See also: SwitchStrategySmoothWeightedRoundRobin, ITask::GetWeight

Note: Weight API

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::SwitchStrategySmoothWeightedRoundRobin::AddActive(), stk::SwitchStrategySmoothWeightedRoundRobin::AddTask(), stk::SwitchStrategySmoothWeightedRoundRobin::GetNext(), stk::SwitchStrategyFixedPriority< 32 >::GetTaskPriority(), and stk::SwitchStrategySmoothWeightedRoundRobin::RemoveActive().

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◆ IsLinked()

bool stk::util::DListEntry< IKernelTask, _ClosedLoop >::IsLinked ( ) const

inlineinherited

Check whether this entry is currently a member of any list.

Returns: true if linked (m_head != NULL); false otherwise.

Definition at line 101 of file stk_linked_list.h.

101{ return (GetHead() != nullptr); }

stk::util::DListEntry< IKernelTask, true >::GetHead

DLHeadType * GetHead() const

Definition stk_linked_list.h:80

◆ IsSleeping()

virtual bool stk::IKernelTask::IsSleeping ( ) const

pure virtual

Check whether the task is currently sleeping.

Returns: True if the task is sleeping, false otherwise.

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::SwitchStrategyMonotonic< MSS_TYPE_RATE >::GetNext(), stk::SwitchStrategyEDF::OnTaskSleep(), stk::SwitchStrategyFixedPriority< 32 >::OnTaskSleep(), stk::SwitchStrategyRoundRobin::OnTaskSleep(), stk::SwitchStrategySmoothWeightedRoundRobin::OnTaskSleep(), stk::SwitchStrategyEDF::OnTaskWake(), stk::SwitchStrategyFixedPriority< 32 >::OnTaskWake(), stk::SwitchStrategyRoundRobin::OnTaskWake(), and stk::SwitchStrategySmoothWeightedRoundRobin::OnTaskWake().

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◆ Link()

void stk::util::DListEntry< IKernelTask, _ClosedLoop >::Link	(	DLHeadType *	head,
		DLEntryType *	next,
		DLEntryType *	prev )

inlineprivateinherited

Wire this entry into a list between prev and next.

Parameters

[in]	head	The owning DListHead. Stored as a back-pointer for IsLinked() and ownership checks.
[in]	next	The entry that will follow this one, or `NULL` if this becomes the last entry.
[in]	prev	The entry that will precede this one, or `NULL` if this becomes the first entry.

Note: Called exclusively by DListHead::Link(). Assumes the entry is not currently linked. Updates the neighbours' forward/back pointers to splice this entry in.

Definition at line 137 of file stk_linked_list.h.

    {
        m_head = head;
        m_next = next;
        m_prev = prev;
 
        if (m_prev != nullptr)
            m_prev->m_next = this;
 
        if (m_next != nullptr)
            m_next->m_prev = this;
    }

◆ operator const IKernelTask *()

stk::util::DListEntry< IKernelTask, _ClosedLoop >::operator const IKernelTask * ( ) const

inlineinherited

Implicit conversion to a const pointer to the host object (T).

Note: Safe because T must derive from DListEntry<T, _ClosedLoop>. Eliminates the need for explicit static_cast at call sites.; MISRA deviation: [STK-DEV-004] Rule 5-2-x.

Definition at line 115 of file stk_linked_list.h.

115{ return static_cast<const T *>(this); }

◆ operator IKernelTask *()

stk::util::DListEntry< IKernelTask, _ClosedLoop >::operator IKernelTask* ( )

inlineinherited

Implicit conversion to a mutable pointer to the host object (T).

Note: Safe because T must derive from DListEntry<T, _ClosedLoop>. Eliminates the need for explicit static_cast at call sites.; MISRA deviation: [STK-DEV-004] Rule 5-2-x.

Definition at line 108 of file stk_linked_list.h.

108{ return static_cast<T *>(this); }

◆ SetCurrentWeight()

virtual void stk::IKernelTask::SetCurrentWeight ( int32_t weight )

pure virtual

Set the current dynamic weight value used by the scheduling strategy.

Parameters

[in] weight New current dynamic weight value.

See also: SwitchStrategySmoothWeightedRoundRobin

Note: Weight API

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Referenced by stk::SwitchStrategySmoothWeightedRoundRobin::AddTask(), stk::SwitchStrategySmoothWeightedRoundRobin::GetNext(), and stk::SwitchStrategySmoothWeightedRoundRobin::OnTaskWake().

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◆ Unlink()

void stk::util::DListEntry< IKernelTask, _ClosedLoop >::Unlink ( )

inlineprivateinherited

Remove this entry from its current list.

Note: Called exclusively by DListHead::Unlink(). Patches the neighbours' pointers to bridge over this entry, then clears m_head, m_next, and m_prev to NULL so the entry is in a clean unlinked state.; Does not update DListHead::m_count or m_first / m_last — those are the responsibility of the calling DListHead::Unlink().

Definition at line 157 of file stk_linked_list.h.

    {
        if (m_prev != nullptr)
            m_prev->m_next = m_next;
 
        if (m_next != nullptr)
            m_next->m_prev = m_prev;
 
        m_head = nullptr;
        m_next = nullptr;
        m_prev = nullptr;
    }

◆ Wake()

virtual void stk::IKernelTask::Wake ( )

pure virtual

Wake a sleeping task on the next scheduling tick.

Warning: The task must currently be sleeping (IsSleeping() == true). Calling Wake() on a non-sleeping task is a programming error and will trigger an assertion in the concrete implementation.

Implemented in stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask.

Member Data Documentation

◆ m_head

DLHeadType* stk::util::DListEntry< IKernelTask, _ClosedLoop >::m_head

privateinherited

Owning list head, or NULL when the entry is not linked.

Definition at line 170 of file stk_linked_list.h.

◆ m_next

DLEntryType* stk::util::DListEntry< IKernelTask, _ClosedLoop >::m_next

privateinherited

Next entry in the list, or NULL (open list boundary) / first entry (closed loop).

Definition at line 171 of file stk_linked_list.h.

◆ m_prev

DLEntryType* stk::util::DListEntry< IKernelTask, _ClosedLoop >::m_prev

privateinherited

Previous entry in the list, or NULL (open list boundary) / last entry (closed loop).

Definition at line 172 of file stk_linked_list.h.

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

stk_common.h

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ DLEntryType

◆ DLHeadType

◆ ListEntryType

◆ ListHeadType

Member Function Documentation

◆ GetCurrentWeight()

◆ GetHead()

◆ GetHrtDeadline()

◆ GetHrtPeriodicity()

◆ GetHrtRelativeDeadline()

◆ GetNext()

◆ GetPrev()

◆ GetUserStack()

◆ GetUserTask()

◆ GetWeight()

◆ IsLinked()

◆ IsSleeping()

◆ Link()

◆ operator const IKernelTask *()

◆ operator IKernelTask *()

◆ SetCurrentWeight()

◆ Unlink()

◆ Wake()

Member Data Documentation

◆ m_head

◆ m_next

◆ m_prev