Concrete implementation of IWaitObject, embedded in each KernelTask slot. More...

#include <stk.h>

Inheritance diagram for stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject:

Collaboration diagram for stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject:

Classes
class	WaitRequest
	Payload stored in the sync object's kernel-side list entry while a task is waiting. More...

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

Public Member Functions
	WaitObject ()
	~WaitObject ()=default
	Destructor.
TId	GetTid () const override
	Get the TId of the task that owns this wait object.
bool	IsTimeout () const override
	Check whether the wait expired due to timeout.
bool	IsWaiting () const
	Check if busy with waiting.
void	Wake (bool timeout) override
	Wake the waiting task (called by ISyncObject when it signals).
bool	Tick (Timeout elapsed_ticks) override
	Advance the timeout countdown by one tick.
void	SetupWait (ISyncObject *sync_obj, Timeout timeout)
	Configure and arm this wait object for a new wait operation.
DLHeadType *	GetHead ()
	Get the list head this entry currently belongs to.
DLEntryType *	GetNext ()
	Get the next entry in the list.
DLEntryType *	GetPrev ()
	Get the previous entry in the list.
bool	IsLinked () const
	Check whether this entry is currently a member of any list.
	operator IWaitObject * ()
	Implicit conversion to a mutable pointer to the host object (T).
	operator const IWaitObject * () const
	Implicit conversion to a const pointer to the host object (T).

Public Attributes
KernelTask *	m_task
	Back-pointer to the owning KernelTask. Set once at construction; never changes.
ISyncObject *	m_sync_obj
	Sync object this wait is registered with, or `NULL` when not waiting.
volatile bool	m_timeout
	`true` if the wait expired due to timeout rather than a Wake() signal.
Timeout	m_time_wait
	Ticks remaining until timeout. Decremented each tick; WAIT_INFINITE means no timeout.

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

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>
class stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject

Concrete implementation of IWaitObject, embedded in each KernelTask slot.

Note: Allocated only when TMode includes KERNEL_SYNC. Zero-size otherwise.; One WaitObject per KernelTask, the back-pointer m_task is wired at KernelTask construction and never changes.

Definition at line 402 of file stk.h.

Member Typedef Documentation

◆ DLEntryType

typedef DListEntry<IWaitObject, TClosedLoop> stk::util::DListEntry< IWaitObject, TClosedLoop >::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<IWaitObject, TClosedLoop> stk::util::DListEntry< IWaitObject, TClosedLoop >::DLHeadType

inherited

Convenience alias for the corresponding list head type.

Definition at line 75 of file stk_linked_list.h.

◆ ListEntryType

typedef DLEntryType stk::IWaitObject::ListEntryType

inherited

List entry type of IWaitObject elements.

Definition at line 345 of file stk_common.h.

◆ ListHeadType

typedef DLHeadType stk::IWaitObject::ListHeadType

inherited

List head type for IWaitObject elements.

Definition at line 340 of file stk_common.h.

Constructor & Destructor Documentation

◆ WaitObject()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::WaitObject ( )

inlineexplicit

Definition at line 404 of file stk.h.

404 : m_task(nullptr), m_sync_obj(nullptr), m_timeout(false), m_time_wait(0)

405 {}

stk::Kernel::KernelTask::WaitObject::m_time_wait

Timeout m_time_wait

Ticks remaining until timeout. Decremented each tick; WAIT_INFINITE means no timeout.

Definition stk.h:500

stk::Kernel::KernelTask::WaitObject::m_timeout

volatile bool m_timeout

true if the wait expired due to timeout rather than a Wake() signal.

Definition stk.h:499

stk::Kernel::KernelTask::WaitObject::m_sync_obj

ISyncObject * m_sync_obj

Sync object this wait is registered with, or NULL when not waiting.

Definition stk.h:498

stk::Kernel::KernelTask::WaitObject::m_task

KernelTask * m_task

Back-pointer to the owning KernelTask. Set once at construction; never changes.

Definition stk.h:497

References m_sync_obj, m_task, m_time_wait, and m_timeout.

◆ ~WaitObject()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::~WaitObject ( )

default

Destructor.

Note: MISRA deviation: [STK-DEV-005] Rule 10-3-2.

References STK_VIRT_DTOR.

Member Function Documentation

◆ GetHead()

DLHeadType * stk::util::DListEntry< IWaitObject, TClosedLoop >::GetHead ( )

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

◆ GetNext()

DLEntryType * stk::util::DListEntry< IWaitObject, TClosedLoop >::GetNext ( )

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 (TClosedLoop == true) this pointer is never NULL when the entry is linked.

Definition at line 93 of file stk_linked_list.h.

93{ return m_next; }

◆ GetPrev()

DLEntryType * stk::util::DListEntry< IWaitObject, TClosedLoop >::GetPrev ( )

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 (TClosedLoop == true) this pointer is never NULL when the entry is linked.

Definition at line 109 of file stk_linked_list.h.

109{ return m_prev; }

◆ GetTid()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

TId stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::GetTid ( ) const

inlineoverridevirtual

Get the TId of the task that owns this wait object.

Returns: TId of m_task.

Implements stk::IWaitObject.

Definition at line 425 of file stk.h.

425{ return m_task->GetTid(); }

References m_task.

◆ IsLinked()

bool stk::util::DListEntry< IWaitObject, TClosedLoop >::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 122 of file stk_linked_list.h.

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

stk::util::DListEntry< IWaitObject, false >::GetHead

DLHeadType * GetHead()

Definition stk_linked_list.h:80

◆ IsTimeout()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

bool stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::IsTimeout ( ) const

inlineoverridevirtual

Check whether the wait expired due to timeout.

Returns: true if the wait timed out before being signalled, false if woken by Wake().

Implements stk::IWaitObject.

Definition at line 430 of file stk.h.

430{ return m_timeout; }

References m_timeout.

◆ IsWaiting()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

bool stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::IsWaiting ( ) const

inline

Check if busy with waiting.

Returns: true if waiting, false if not.

Definition at line 435 of file stk.h.

435{ return (m_sync_obj != nullptr); }

References m_sync_obj.

Referenced by SetupWait(), and Wake().

Here is the caller graph for this function:

◆ Link()

void stk::util::DListEntry< IWaitObject, TClosedLoop >::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 157 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 IWaitObject *()

stk::util::DListEntry< IWaitObject, TClosedLoop >::operator const IWaitObject * ( ) const

inlineinherited

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

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

Definition at line 136 of file stk_linked_list.h.

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

◆ operator IWaitObject *()

stk::util::DListEntry< IWaitObject, TClosedLoop >::operator IWaitObject* ( )

inlineinherited

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

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

Definition at line 129 of file stk_linked_list.h.

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

◆ SetupWait()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

void stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::SetupWait	(	ISyncObject *	sync_obj,
		Timeout	timeout )

inline

Configure and arm this wait object for a new wait operation.

Parameters

[in]	sync_obj	The synchronization object to wait on. Must not already have this wait object registered (asserted).
[in]	timeout	Maximum ticks to wait, or WAIT_INFINITE for no timeout.

Note: Registers this object with sync_obj's wait list via AddWaitObject(). Must be paired with a matching Wake() or timeout expiry.

Definition at line 486 of file stk.h.

            {
                STK_ASSERT(!IsWaiting());
 
                m_sync_obj  = sync_obj;
                m_time_wait = timeout;
                m_timeout   = false;
 
                sync_obj->AddWaitObject(this);
            }

References stk::ISyncObject::AddWaitObject(), IsWaiting(), m_sync_obj, m_time_wait, m_timeout, and STK_ASSERT.

Here is the call graph for this function:

◆ Tick()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

bool stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::Tick ( Timeout elapsed_ticks )

inlineoverridevirtual

Advance the timeout countdown by one tick.

Returns: true if the wait is still active (not yet timed out), false if the timeout just expired (caller should stop ticking this object).

Note: Called by UpdateSyncObjects() each kernel tick. WAIT_INFINITE waits never time out and always return true.

Implements stk::IWaitObject.

Definition at line 461 of file stk.h.

            {
                if (m_time_wait != WAIT_INFINITE)
                {
                    if (!m_timeout)
                    {                  
                        m_time_wait -= elapsed_ticks;
 
                        if (m_time_wait <= 0)
                        {
                            m_timeout = true;
                        }
                    }
                }
 
                return !m_timeout;
            }

References m_time_wait, m_timeout, and stk::WAIT_INFINITE.

◆ Unlink()

void stk::util::DListEntry< IWaitObject, TClosedLoop >::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 181 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()

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

void stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::Wake ( bool timeout )

inlineoverridevirtual

Wake the waiting task (called by ISyncObject when it signals).

Parameters

[in] timeout true if woken because the timeout expired, false if signalled.

Note: Clears m_time_wait, records the timeout flag, removes this object from m_sync_obj's wait list, nulls m_sync_obj, then calls m_task->Wake().

Implements stk::IWaitObject.

Definition at line 442 of file stk.h.

            {
                STK_ASSERT(IsWaiting());
 
                m_timeout   = timeout;
                m_time_wait = 0;
 
                m_sync_obj->RemoveWaitObject(this);
                m_sync_obj = nullptr;
 
                return m_task->Wake();
            }

References IsWaiting(), m_sync_obj, m_task, m_time_wait, m_timeout, and STK_ASSERT.

Here is the call graph for this function:

Member Data Documentation

◆ m_head

DLHeadType* stk::util::DListEntry< IWaitObject, TClosedLoop >::m_head

privateinherited

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

Definition at line 198 of file stk_linked_list.h.

◆ m_next

DLEntryType* stk::util::DListEntry< IWaitObject, TClosedLoop >::m_next

privateinherited

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

Definition at line 199 of file stk_linked_list.h.

◆ m_prev

DLEntryType* stk::util::DListEntry< IWaitObject, TClosedLoop >::m_prev

privateinherited

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

Definition at line 200 of file stk_linked_list.h.

◆ m_sync_obj

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

ISyncObject* stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::m_sync_obj

Sync object this wait is registered with, or NULL when not waiting.

Definition at line 498 of file stk.h.

Referenced by IsWaiting(), SetupWait(), WaitObject(), and Wake().

◆ m_task

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

KernelTask* stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::m_task

Back-pointer to the owning KernelTask. Set once at construction; never changes.

Definition at line 497 of file stk.h.

Referenced by GetTid(), WaitObject(), and Wake().

◆ m_time_wait

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

Timeout stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::m_time_wait

Ticks remaining until timeout. Decremented each tick; WAIT_INFINITE means no timeout.

Definition at line 500 of file stk.h.

Referenced by SetupWait(), Tick(), WaitObject(), and Wake().

◆ m_timeout

template<uint8_t TMode, uint32_t TSize, class TStrategy, class TPlatform>

volatile bool stk::Kernel< TMode, TSize, TStrategy, TPlatform >::KernelTask::WaitObject::m_timeout

true if the wait expired due to timeout rather than a Wake() signal.

Definition at line 499 of file stk.h.

Referenced by IsTimeout(), SetupWait(), Tick(), WaitObject(), and Wake().

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

stk.h

Classes

Public Types

Public Member Functions

Public Attributes

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ DLEntryType

◆ DLHeadType

◆ ListEntryType

◆ ListHeadType

Constructor & Destructor Documentation

◆ WaitObject()

◆ ~WaitObject()

Member Function Documentation

◆ GetHead()

◆ GetNext()

◆ GetPrev()

◆ GetTid()

◆ IsLinked()

◆ IsTimeout()

◆ IsWaiting()

◆ Link()

◆ operator const IWaitObject *()

◆ operator IWaitObject *()

◆ SetupWait()

◆ Tick()

◆ Unlink()

◆ Wake()

Member Data Documentation

◆ m_head

◆ m_next

◆ m_prev

◆ m_sync_obj

◆ m_task

◆ m_time_wait

◆ m_timeout