QXK Class Reference

QXK dual-mode kernel (QXK namespace emulated as a "class" in C). More...

Static Public Member Functions
void	QXK_onIdle (void)
	QXK idle callback (customized in BSPs for QXK).
QSchedStatus	QXK_schedLock (uint8_t const ceiling)
	QXK selective scheduler lock.
void	QXK_schedUnlock (QSchedStatus const stat)
	QXK selective scheduler unlock.
QActive *	QXK_current (void)
	Obtain the currently executing active-object/thread.
void	QXK_contextSw_ (QActive *const next)
	QXK context switch management.
	__attribute__ ((used))

Static Private Member Functions
uint_fast8_t	QXK_sched_ (void)
	QXK scheduler finds the highest-priority thread ready to run.
void	QXK_activate_ (void)
	QXK activator activates the next AO that preempts the currently executing AOs.
void	QXK_threadExit_ (void)
	called right before QXThread exits

Private Attributes
QXK_Attr	QXK_priv_

Detailed Description

QXK dual-mode kernel (QXK namespace emulated as a "class" in C).

See also

• Preemptive Non-Blocking Kernel

The QXK class is related to the following classes:

• QXThread
• QXSemaphore
• QXMutex

Definition at line 33 of file qxk.h.

Member Function Documentation

QXK_onIdle()

void QXK_onIdle ( void )

static

QXK idle callback (customized in BSPs for QXK).

Details

QXK_onIdle() is called continuously by the QXK idle thread. This callback gives the application an opportunity to enter a power-saving CPU mode, or perform some other idle processing.

Note

QXK_onIdle() is invoked with interrupts enabled and must also return with interrupts enabled.

QXK_schedLock()

QSchedStatus QXK_schedLock ( uint8_t const ceiling )

static

QXK selective scheduler lock.

Details

This function locks the QXK scheduler to the specified ceiling.

Parameters

[in]

ceiling

preemption ceiling to which the QXK scheduler needs to be locked

Return values

lock-status

The previous QXK Scheduler lock status, which is to be used to unlock the scheduler by restoring its previous lock status in QXK_schedUnlock().

Note

A QXK scheduler can be locked from both basic threads (AOs) and extended threads and the scheduler locks can nest.

QXK_schedLock() must be always followed by the corresponding QXK_schedUnlock().

Attention

QXK will fire an assertion if a thread holding the lock attempts to block.

See also

• QXK_schedUnlock()

Usage

The following example shows how to lock and unlock the QXK scheduler:

uint32_t BSP_random(void) {
    uint32_rnd;
 
    QSchedStatus lockStat = QXK_schedLock(N_PHILO); // <== N_PHILO ceiling
    . . . // access/manipulate the shared random seed resource
    QXK_schedUnlock(lockStat); // <=== unlock
 
    return rnd;
}

QXK_schedUnlock()

void QXK_schedUnlock ( QSchedStatus const stat )

static

QXK selective scheduler unlock.

Details

This function unlocks the QXK scheduler to the previous status.

Parameters

[in]

stat

previous QXK Scheduler lock status returned from QXK_schedLock()

Note

A QXK scheduler can be locked from both basic threads (AOs) and extended threads and the scheduler locks can nest.

QXK_schedUnlock() must always follow the corresponding QXK_schedLock().

Usage

The following example shows how to lock and unlock the QXK scheduler:

uint32_t BSP_random(void) {
    uint32_rnd;
 
    QSchedStatus lockStat = QXK_schedLock(N_PHILO); // <== N_PHILO ceiling
    . . . // access/manipulate the shared random seed resource
    QXK_schedUnlock(lockStat); // <=== unlock
 
    return rnd;
}

Definition at line 85 of file qxk.c.

QXK_current()

QActive * QXK_current ( void )

static

Obtain the currently executing active-object/thread.

Details

Return values

AO/thread

Pointer to the currently executing active-object/thread

Definition at line 119 of file qxk.c.

QXK_sched_()

uint_fast8_t QXK_sched_ ( void )

staticprivate

QXK scheduler finds the highest-priority thread ready to run.

Details

The QXK scheduler finds the priority of the highest-priority thread that is ready to run.

Return values

priority

1-based priority of the the thread (basic or extended) run next, or zero if no eligible thread is found.

Attention

QXK_sched_() must be always called with interrupts disabled and returns with interrupts disabled.

Definition at line 138 of file qxk.c.

QXK_activate_()

void QXK_activate_ ( void )

staticprivate

QXK activator activates the next AO that preempts the currently executing AOs.

Details

QXK_activate_() activates ready-to run AOs that are above the initial active priority (QXK_priv_.actPrio).

Attention

QXK_activate_() must be always called with interrupts disabled and returns with interrupts disabled.

Definition at line 190 of file qxk.c.

QXK_contextSw_()

void QXK_contextSw_ ( QActive *const next )

static

QXK context switch management.

Details

This internal function handles context switch. It calls QF_onContextSw() (if #QF_ON_CONTEXT_SW is defined and performs software tracing (if Q_SPY is defined).

Parameters

[in]

next

pointer to the next thread (NULL for basic-thread)

Attention

QXK_contextSw_() is invoked with interrupts disabled and must also return with interrupts disabled.

QXK_threadExit_()

void QXK_threadExit_ ( void )

staticprivate

called right before QXThread exits

Details

Called when the extended-thread handler function returns.

Note

Most thread handler functions are structured as endless loops that never return. But it is also possible to structure threads as one-shot functions that perform their job and return. In that case this function performs cleanup after the thread.

Definition at line 323 of file qxk.c.

__attribute__()

__attribute__ ( (used) )

static

Definition at line 47 of file qxk.c.

Member Data Documentation

QXK_priv_

QXK_Attr QXK_priv_

private

Definition at line 59 of file qxk.h.