QXK/C eXtended (blocking) thread. More...

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Data Structures
struct	QXThread
	eXtended (blocking) thread of the QXK preemptive kernel More...

struct	QXSemaphore
	Counting Semaphore of the QXK preemptive kernel. More...

struct	QXMutex
	Blocking Mutex the QXK preemptive kernel. More...

Macros
#define	QXTHREAD_START(me_, prio_, qSto_, qLen_, stkSto_, stkLen_, par_)
	Polymorphically start an extended thread. More...

#define	QXTHREAD_POST_X(me_, e_, margin_, sender_) QACTIVE_POST_X(&(me_)->super, (e_), (margin_), (sender_))

#define	QXTHREAD_NO_TIMEOUT ((uint_fast16_t)0)
	no-timeout special timeout value when blocking on queues or semaphores More...

#define	Q_XTHREAD_CAST(handler_) ((QXThreadHandler)(handler_))
	Perform cast to QXThreadHandler. More...

Typedefs
typedef QActiveVtbl	QXThreadVtbl
	Virtual Table for the QXThread class (inherited from QActiveVtbl) More...

typedef void(*	QXThreadHandler) (QXThread *const me)
	Thread handler pointer-to-function. More...

Functions
void	QXThread_ctor (QXThread *const me, QXThreadHandler handler, uint_fast8_t tickRate)
	constructor of an extended-thread More...

bool	QXThread_delay (uint_fast16_t const nTicks)
	delay (block) the current extended thread for a specified # ticks More...

bool	QXThread_delayCancel (QXThread *const me)
	cancel the delay More...

QEvt const *	QXThread_queueGet (uint_fast16_t const nTicks)
	obtain a message from the private message queue (block if no messages) More...

void	QXSemaphore_init (QXSemaphore *const me, uint_fast16_t count, uint_fast16_t max_count)
	initialize the counting semaphore More...

bool	QXSemaphore_wait (QXSemaphore *const me, uint_fast16_t const nTicks)
	wait (block) on the semaphore More...

bool	QXSemaphore_tryWait (QXSemaphore *const me)
	try wait on the semaphore (non-blocking) More...

bool	QXSemaphore_signal (QXSemaphore *const me)
	signal (unblock) the semaphore More...

void	QXMutex_init (QXMutex *const me, uint_fast8_t ceiling)
	initialize the QXK priority-ceiling mutex QXMutex More...

bool	QXMutex_lock (QXMutex *const me, uint_fast16_t const nTicks)
	lock the QXK priority-ceiling mutex QXMutex More...

bool	QXMutex_tryLock (QXMutex *const me)
	try to lock the QXK priority-ceiling mutex QXMutex More...

void	QXMutex_unlock (QXMutex *const me)
	unlock the QXK priority-ceiling mutex QXMutex More...

Detailed Description

QXK/C eXtended (blocking) thread.

Definition in file qxthread.h.

Data Structure Documentation

◆ QXThread

struct QXThread

eXtended (blocking) thread of the QXK preemptive kernel

Description: QXThread represents the eXtended (blocking) thread of the QXK preemptive kernel. Each extended thread in the application must be represented by the corresponding QXThread instance

Note: Typically, QXThread is instantiated directly in the application code. The customization of the thread occurs in the QXThread_ctor(), where you provide the thred-handler function as the parameter.

See also

Usage: The following example illustrates how to instantiate and use an extended thread in your application.
#include "qpc.h"
Q_DEFINE_THIS_FILE
QXThread blinky; /* QXK extended-thread object */
uint32_t stack_blinky[80]; /* stack for the thread */
void main_blinky(QXThread * const me) { /* thread function */
while (1) {
uint32_t volatile i;
for (i = 1500U; i != 0U; --i) {
BSP_ledGreenOn();
BSP_ledGreenOff();
}
QXThread_delay(1U); /* block for 1 tick */
}
}
int main() {
. . .
/* initialize and start blinky thread */
QXThread_ctor(&blinky, &main_blinky, 0);
QXTHREAD_START(&blinky,
5U, /* priority */
(void *)0, 0, /* message queue (not used) */
stack_blinky, sizeof(stack_blinky), /* stack */
(void *)0); /* extra parameter (not used) */
. . .
return QF_run(); /* run the application */
}

Definition at line 71 of file qxthread.h.

Collaboration diagram for QXThread:

Data Fields
QActive	super	inherited QActive
QTimeEvt	timeEvt	time event to handle blocking timeouts

◆ QXSemaphore

struct QXSemaphore

Counting Semaphore of the QXK preemptive kernel.

Description: QXSemaphore is a blocking mechanism intended primarily for signaling extended threads. The semaphore is initialized with the maximum count (see QXSemaphore_init()), which allows you to create a binary semaphore (when the maximum count is 1) and counting semaphore when the maximum count is > 1.

See also

Usage: The following example illustrates how to instantiate and use the semaphore in your application.
QXSemaphore BTN_sema; /* semaphore to signal a button press */
int main() {
. . .
/* initialize the BTN_sema semaphore as binary, signaling semaphore */
QXSemaphore_init(&BTN_sema, /* pointer to semaphore to initialize */
0U, /* initial semaphore count (singaling semaphore) */
1U); /* maximum semaphore count (binary semaphore) */
. . .
}
void main_threadXYZ(QXThread * const me) {
while (1) {
. . .
QXSemaphore_wait(&BTN_sema, /* pointer to semaphore to wait on */
QXTHREAD_NO_TIMEOUT); /* timeout for waiting */
. . .
}
}
void GPIO_Handler(void) {
. . .
QXSemaphore_signal(&BTN_sema); /* pointer to semaphore to signal */
. . .
}

Definition at line 192 of file qxthread.h.

Collaboration diagram for QXSemaphore:

Data Fields
QPSet	waitSet	set of extended-threads waiting on this semaphore
uint16_t volatile	count	semaphore up-down counter
uint16_t	max_count	maximum value of the semaphore counter

◆ QXMutex

struct QXMutex

Blocking Mutex the QXK preemptive kernel.

Description: QXMutex is a blocking mutual exclusion mechanism that can also apply the priority ceiling protocol to avoid unbounded priority inversion (if initialized with a non-zero ceiling priority, see QXMutex_init()). In that case, QXMutex requires its own uinque QP priority level, which cannot be used by any thread or any other QXMutex. If initialzied with zero ceiling priority, QXMutex does not use the priority ceiling protocol and does not require a unique QP priority (see QXMutex_init()). QXMutex is recursive (reentrant), which means that it can be locked mutiliple times (up to 255 levels) by the same thread without causing deadlock. QXMutex is primarily intended for the extened (blocking) threads, but can also be used by the basic threads through the non-blocking QXMutex_tryLock() API.

Note: QXMutex should be used in situations when at least one of the extended threads contending for the mutex blocks while holding the mutex (between the QXMutex_lock() and QXMutex_unlock() operations). If no blocking is needed while holding the mutex, the more efficient non-blocking mechanism of selective QXK scheduler locking should be used instead. Selective scheduler locking is available for both basic threads and extendedthreads", so it is applicable to situations where resources are shared among all these threads.

See also

Usage: The following example illustrates how to instantiate and use the mutex in your application.
QXMutex l_rndMutex; /* mutex to protect the random number generator */
void BSP_randomSeed(uint32_t seed) {
QXMutex_init(&l_rndMutex, N_PHILO); /* <== initialize the mutex */
l_rnd = seed;
}
uint32_t BSP_random(void) { /* a very cheap pseudo-random-number generator */
uint32_t rnd;
QXMutex_lock(&l_rndMutex); /* <== lock the shared random seed */
/* "Super-Duper" Linear Congruential Generator (LCG) */
rnd = l_rnd * (3U*7U*11U*13U*23U);
l_rnd = rnd; /* set for the next time */
QXMutex_unlock(&l_rndMutex); /* <== unlock the shared random seed */
return rnd;
}

Definition at line 254 of file qxthread.h.

Collaboration diagram for QXMutex:

Data Fields
QPSet	waitSet	set of extended-threads waiting on this mutex
uint8_t volatile	lockNest	lock-nesting up-down counter
uint8_t volatile	holderPrio	priority of the lock holder thread
uint8_t	ceiling	prioirty ceiling of this mutex

Macro Definition Documentation

◆ QXTHREAD_START

#define QXTHREAD_START	(	me_,
		prio_,
		qSto_,
		qLen_,
		stkSto_,
		stkLen_,
		par_
	)

Value:

do {\
    Q_ASSERT((me_)->super.super.vptr);                                       \
    ((*((QActiveVtbl const *)((me_)->super.super.vptr))->start)(             \
        &(me_)->super, (prio_), (QEvt const **)(qSto_), (qLen_),             \
        (stkSto_), (stkLen_), (par_)));                                      \
} while (0)

Polymorphically start an extended thread.

Description: Starts execution of the thread and registers the thread with the framework.

Parameters

[in,out]	me_	pointer (see Object Orientation)
[in]	prio_	priority of the extended-thread
[in]	qSto_	pointer to the storage for the ring buffer of the message queue (possibly NULL)
[in]	qLen_	length of the message queue [events] (possibly 0)
[in]	stkSto_	pointer to the stack storage (required)
[in]	stkSize_	stack size [bytes]
[in]	par_	pointer to the additional port-specific parameter(s) (might be NULL).

Usage: #include "qpc.h"
Q_DEFINE_THIS_FILE
int main() {
. . .
/* stack for the QXK's idle thread */
static uint64_t idleStackSto[32];
Test_ctor(); /* instantiate the Test "naked" thread */
QF_init(); /* initialize the framework */
BSP_init(); /* initialize the Board Support Package */
/* initialize QXK... */
QXK_init(idleStackSto, sizeof(idleStackSto));
/* initialize publish-subscribe... */
QF_psInit(subscrSto, Q_DIM(subscrSto));
/* initialize event pools... */
QF_poolInit(smlPoolSto, sizeof(smlPoolSto), sizeof(smlPoolSto[0]));
/* start the active objects (basic-threads)... */
QACTIVE_START(AO_Table, /* AO to start */
(uint_fast8_t)(N_PHILO + 2), /* QP priority of the AO */
tableQueueSto, /* event queue storage */
Q_DIM(tableQueueSto), /* queue length [events] */
tableStackSto, /* stack storage */
sizeof(tableStackSto), /* stack size [bytes] */
(QEvt *)0); /* initialization event */
. . .
/* start the extended-threads... */
QXTHREAD_START(XT_Test, /* Thread to start */
(uint_fast8_t)10U, /* QP priority of the thread */
testQueueSto, /* message queue storage */
Q_DIM(testQueueSto), /* message length [events] */
testStackSto, /* stack storage */
sizeof(testStackSto), /* stack size [bytes] */
(QEvt *)0); /* initialization event */
return QF_run(); /* run the QF application */
}

Definition at line 101 of file qxthread.h.

◆ QXTHREAD_POST_X

#define QXTHREAD_POST_X	(	me_,
		e_,
		margin_,
		sender_
	)	QACTIVE_POST_X(&(me_)->super, (e_), (margin_), (sender_))

Description: This macro does not assert if the queue overflows and cannot accept the event with the specified margin of free slots remaining.

Parameters

[in,out]	me_	pointer (see Object Orientation)
[in]	e_	pointer to the event to post
[in]	margin_	the minimum free slots in the queue, which must still be available after posting the event. The special value QF_NO_MARGIN causes asserting failure in case event allocation fails.
[in]	sender_	pointer to the sender object.

Returns: 'true' if the posting succeeded, and 'false' if the posting failed due to insufficient margin of free slots available in the queue.

Note: The sender_ parameter is actually only used when QS tracing is enabled (macro Q_SPY is defined). When QS software tracing is disabled, the QXTHREAD_POST_X() macro does not pass the sender_ argument, so the overhead of passing this extra argument is entirely avoided.; The pointer to the sender object is not necessarily a pointer to an active object. In fact, if QXTHREAD_POST_X() is called from an interrupt or other context, you can create a unique object just to unambiguously identify the sender of the event.

Usage: extern QActive *AO_Table;
. . .
/* typically inside a state machine action */
TableEvt *pe;
Q_NEW_X(pe, TableEvt, 5U, HUNGRY_SIG); /* dynamic alloc, margin==5 */
if (pe != (TableEvt *)0) {
pe->philNum = me->num;
QACTIVE_POST_X(AO_Table, &pe->super, 3U, me); /* margin==3 */
}
. . .

Definition at line 147 of file qxthread.h.

◆ QXTHREAD_NO_TIMEOUT

#define QXTHREAD_NO_TIMEOUT ((uint_fast16_t)0)

no-timeout special timeout value when blocking on queues or semaphores

Definition at line 160 of file qxthread.h.

◆ Q_XTHREAD_CAST

#define Q_XTHREAD_CAST ( handler_ ) ((QXThreadHandler)(handler_))

Perform cast to QXThreadHandler.

Description: This macro encapsulates the cast of a specific thread handler function pointer to QXThreadHandler, which violates MISRA-C 2004 rule 11.4(adv). This macro helps to localize this deviation.

Definition at line 169 of file qxthread.h.

Typedef Documentation

◆ QXThreadVtbl

typedef QActiveVtbl QXThreadVtbl

Virtual Table for the QXThread class (inherited from QActiveVtbl)

Note: QXThread inherits QActive without adding any new virtual functions and therefore, QXThreadVtbl is typedef'ed as QActiveVtbl.

Definition at line 82 of file qxthread.h.

◆ QXThreadHandler

typedef void(* QXThreadHandler) (QXThread *const me)

Thread handler pointer-to-function.

Definition at line 109 of file qxthread.h.

Function Documentation

◆ QXThread_ctor()

void QXThread_ctor	(	QXThread *const	me,
		QXThreadHandler	handler,
		uint_fast8_t	tickRate
	)

constructor of an extended-thread

◆ QXThread_delay()

bool QXThread_delay ( uint_fast16_t const nTicks )

delay (block) the current extended thread for a specified # ticks

◆ QXThread_delayCancel()

bool QXThread_delayCancel ( QXThread *const me )

cancel the delay

◆ QXThread_queueGet()

QEvt const* QXThread_queueGet ( uint_fast16_t const nTicks )

obtain a message from the private message queue (block if no messages)

◆ QXSemaphore_init()

void QXSemaphore_init	(	QXSemaphore *const	me,
		uint_fast16_t	count,
		uint_fast16_t	max_count
	)

initialize the counting semaphore

◆ QXSemaphore_wait()

bool QXSemaphore_wait	(	QXSemaphore *const	me,
		uint_fast16_t const	nTicks
	)

wait (block) on the semaphore

◆ QXSemaphore_tryWait()

bool QXSemaphore_tryWait ( QXSemaphore *const me )

try wait on the semaphore (non-blocking)

◆ QXSemaphore_signal()

bool QXSemaphore_signal ( QXSemaphore *const me )

signal (unblock) the semaphore

◆ QXMutex_init()

void QXMutex_init	(	QXMutex *const	me,
		uint_fast8_t	ceiling
	)

initialize the QXK priority-ceiling mutex QXMutex

◆ QXMutex_lock()

bool QXMutex_lock	(	QXMutex *const	me,
		uint_fast16_t const	nTicks
	)

lock the QXK priority-ceiling mutex QXMutex

◆ QXMutex_tryLock()

bool QXMutex_tryLock ( QXMutex *const me )

try to lock the QXK priority-ceiling mutex QXMutex

◆ QXMutex_unlock()

void QXMutex_unlock ( QXMutex *const me )

unlock the QXK priority-ceiling mutex QXMutex

Data Structures

Macros

Typedefs

Functions

Detailed Description

Data Structure Documentation

◆ QXThread

◆ QXSemaphore

◆ QXMutex

Macro Definition Documentation

◆ QXTHREAD_START

◆ QXTHREAD_POST_X

◆ QXTHREAD_NO_TIMEOUT

◆ Q_XTHREAD_CAST

Typedef Documentation

◆ QXThreadVtbl

◆ QXThreadHandler

Function Documentation

◆ QXThread_ctor()

◆ QXThread_delay()

◆ QXThread_delayCancel()

◆ QXThread_queueGet()

◆ QXSemaphore_init()

◆ QXSemaphore_wait()

◆ QXSemaphore_tryWait()

◆ QXSemaphore_signal()

◆ QXMutex_init()

◆ QXMutex_lock()

◆ QXMutex_tryLock()

◆ QXMutex_unlock()