QP::QXK Class Reference

QXK dual-mode (non-blocking / blocking) kernel. More...

#include <qxk.hpp>

Public Member Functions
	QXK () noexcept

Static Public Member Functions
static QSchedStatus	schedLock (std::uint8_t const ceiling) noexcept
	QXK Scheduler lock.
static void	schedUnlock (QSchedStatus const stat) noexcept
	QXK Scheduler unlock.
static void	onIdle ()
	QXK idle callback (customized in BSPs for QXK).
static QActive *	current () noexcept
static std::uint_fast8_t	sched_ () noexcept
	QXK scheduler finds the highest-priority thread ready to run.
static void	threadExit_ () noexcept
	Called when QP::QXThread exits.
static void	activate_ ()
	QXK activator activates the next active object. The activated AO preempts the currently executing AOs.
static QMState *	qmstate_cast_ (void *ptr)

Public Attributes
QActive *	curr
QActive *	next
QActive *	prev
std::uint8_t	actPrio
std::uint8_t	lockCeil
std::uint8_t	lockHolder
std::uint8_t	intNest
QPSet	readySet
	Set of active-objects/threads that are ready to run in the QXK kernel.

Static Public Attributes
static constexpr QSignal	DELAY_SIG { 1 }
static constexpr QSignal	TIMEOUT_SIG { 2 }

Detailed Description

QXK dual-mode (non-blocking / blocking) kernel.

See also

QXK Dual-Mode Kernel The QXK class is related to the following classes:

• QP::QXThread
• QP::QXSemaphore
• QP::QXMutex

Definition at line 40 of file qxk.hpp.

Constructor & Destructor Documentation

QXK()

QP::QXK::QXK ( )

noexcept

Definition at line 53 of file qxk.cpp.

Member Function Documentation

schedLock()

QSchedStatus QP::QXK::schedLock ( std::uint8_t const ceiling )

staticnoexcept

QXK 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

Returns

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:

std::uint32_t BSP::random() {
    QP::QSchedStatus lockStat = QP::QXK::schedLock(N_PHILO); // <== lock
    std::uint32_rnd = ...
    . . . // access/manipulate the shared random seed resource
    QP::QXK::schedUnlock(lockStat);
 
    return rnd;
}

Definition at line 65 of file qxk.cpp.

schedUnlock()

void QP::QXK::schedUnlock ( QSchedStatus const stat )

staticnoexcept

QXK 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:

std::uint32_t BSP::random() {
    QP::QSchedStatus lockStat = QP::QXK::schedLock(N_PHILO);
    std::uint32_rnd = ...
    . . . // access/manipulate the shared random seed resource
    QP::QXK::schedUnlock(lockStat); // <== unlock
 
    return rnd;
}

Definition at line 99 of file qxk.cpp.

onIdle()

void QP::QXK::onIdle ( )

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.

current()

QActive * QP::QXK::current ( )

staticnoexcept

Definition at line 132 of file qxk.cpp.

sched_()

std::uint_fast8_t QP::QXK::sched_ ( )

staticnoexcept

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.

Returns

the 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. QXK::sched_() is defined with the "C" linkage (extern "C").

Definition at line 150 of file qxk.cpp.

threadExit_()

void QP::QXK::threadExit_ ( )

staticnoexcept

Called when QP::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 336 of file qxk.cpp.

activate_()

void QP::QXK::activate_ ( )

static

QXK activator activates the next active object. The activated AO 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. QXK::activate_() is defined with the "C" linkage (extern "C").

Definition at line 198 of file qxk.cpp.

qmstate_cast_()

QMState * QP::QXK::qmstate_cast_ ( void * ptr )

inlinestatic

Definition at line 67 of file qxk.hpp.

Member Data Documentation

curr

QActive* QP::QXK::curr

Definition at line 44 of file qxk.hpp.

next

QActive* QP::QXK::next

Definition at line 45 of file qxk.hpp.

prev

QActive* QP::QXK::prev

Definition at line 46 of file qxk.hpp.

actPrio

std::uint8_t QP::QXK::actPrio

Definition at line 47 of file qxk.hpp.

lockCeil

std::uint8_t QP::QXK::lockCeil

Definition at line 48 of file qxk.hpp.

lockHolder

std::uint8_t QP::QXK::lockHolder

Definition at line 49 of file qxk.hpp.

intNest

std::uint8_t QP::QXK::intNest

Definition at line 50 of file qxk.hpp.

readySet

QPSet QP::QXK::readySet

Set of active-objects/threads that are ready to run in the QXK kernel.

Definition at line 51 of file qxk.hpp.

DELAY_SIG

QSignal QP::QXK::DELAY_SIG { 1 }

staticconstexpr

Definition at line 64 of file qxk.hpp.

TIMEOUT_SIG

QSignal QP::QXK::TIMEOUT_SIG { 2 }

staticconstexpr

Definition at line 65 of file qxk.hpp.

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

• qxk.hpp
• qxk.cpp
• qxk.dox