This commit is contained in:
Robin Müller 2020-06-22 23:46:44 +02:00
parent dadc867d9e
commit 6a7f47e06d
2 changed files with 45 additions and 17 deletions

View File

@ -82,7 +82,7 @@ ReturnValue_t FixedTimeslotTask::checkSequence() const {
void FixedTimeslotTask::taskFunctionality() {
// A local iterator for the Polling Sequence Table is created to find the
// start time for the first entry.
SlotListIter slotListIter = pst.current;
auto slotListIter = pst.current;
//The start time for the first entry is read.
uint32_t intervalMs = slotListIter->pollingTimeMs;
@ -90,9 +90,9 @@ void FixedTimeslotTask::taskFunctionality() {
TickType_t xLastWakeTime;
/* The xLastWakeTime variable needs to be initialized with the current tick
count. Note that this is the only time the variable is written to explicitly.
After this assignment, xLastWakeTime is updated automatically internally within
vTaskDelayUntil(). */
count. Note that this is the only time the variable is written to
explicitly. After this assignment, xLastWakeTime is updated automatically
internally within vTaskDelayUntil(). */
xLastWakeTime = xTaskGetTickCount();
// wait for first entry's start time
@ -109,18 +109,8 @@ void FixedTimeslotTask::taskFunctionality() {
intervalMs = this->pst.getIntervalToPreviousSlotMs();
interval = pdMS_TO_TICKS(intervalMs);
/* If all operations are finished and the difference of the
* current time minus the last wake time is larger than the
* expected wait period, a deadline was missed. */
if(xTaskGetTickCount() - xLastWakeTime >= interval) {
#ifdef DEBUG
sif::warning << "FixedTimeslotTask: " << pcTaskGetName(NULL) <<
" missed deadline!\n" << std::flush;
#endif
if(deadlineMissedFunc != nullptr) {
this->deadlineMissedFunc();
}
}
checkMissedDeadline(xLastWakeTime, interval);
// Wait for the interval. This exits immediately if a deadline was
// missed while also updating the last wake time.
vTaskDelayUntil(&xLastWakeTime, interval);
@ -128,6 +118,40 @@ void FixedTimeslotTask::taskFunctionality() {
}
}
void FixedTimeslotTask::checkMissedDeadline(const TickType_t xLastWakeTime,
const TickType_t interval) {
/* Check whether deadline was missed while also taking overflows
* into account. Drawing this on paper with a timeline helps to understand
* it. */
TickType_t currentTickCount = xTaskGetTickCount();
TickType_t timeToWake = xLastWakeTime + interval;
// Tick count has overflown
if(currentTickCount < xLastWakeTime) {
// Time to wake has overflown as well. If the tick count
// is larger than the time to wake, a deadline was missed.
if(timeToWake < xLastWakeTime and
currentTickCount > timeToWake) {
handleMissedDeadline();
}
}
// No tick count overflow. If the timeToWake has not overflown
// and the current tick count is larger than the time to wake,
// a deadline was missed.
else if(timeToWake > xLastWakeTime and currentTickCount > timeToWake) {
handleMissedDeadline();
}
}
void FixedTimeslotTask::handleMissedDeadline() {
#ifdef DEBUG
sif::warning << "FixedTimeslotTask: " << pcTaskGetName(NULL) <<
" missed deadline!\n" << std::flush;
#endif
if(deadlineMissedFunc != nullptr) {
this->deadlineMissedFunc();
}
}
ReturnValue_t FixedTimeslotTask::sleepFor(uint32_t ms) {
vTaskDelay(pdMS_TO_TICKS(ms));
return HasReturnvaluesIF::RETURN_OK;

View File

@ -12,7 +12,7 @@ class FixedTimeslotTask: public FixedTimeslotTaskIF {
public:
/**
* Keep in Mind that you need to call before this vTaskStartScheduler()!
* Keep in Mind that you need to call before vTaskStartScheduler()!
* A lot of task parameters are set in "FreeRTOSConfig.h".
* @param name Name of the task, lenght limited by configMAX_TASK_NAME_LEN
* @param setPriority Number of priorities specified by
@ -89,6 +89,10 @@ protected:
* OS's System Calls to keep the timing of the periods.
*/
void taskFunctionality(void);
void checkMissedDeadline(const TickType_t xLastWakeTime,
const TickType_t interval);
void handleMissedDeadline();
};
#endif /* POLLINGTASK_H_ */