/**
* @brief Change thread priority.
* @note This can interfere with the priority inheritance mechanism.
*/
osStatus osThreadSetPriority(osThreadId thread_id, osPriority newprio) {
osPriority oldprio;
thread_t * tp = (thread_t *)thread_id;
chSysLock();
/* Changing priority.*/
#if CH_CFG_USE_MUTEXES
oldprio = (osPriority)tp->p_realprio;
if ((tp->p_prio == tp->p_realprio) || ((tprio_t)newprio > tp->p_prio))
tp->p_prio = (tprio_t)newprio;
tp->p_realprio = (tprio_t)newprio;
#else
oldprio = tp->p_prio;
tp->p_prio = (tprio_t)newprio;
#endif
/* The following states need priority queues reordering.*/
switch (tp->p_state) {
#if CH_CFG_USE_MUTEXES | \
CH_CFG_USE_CONDVARS | \
(CH_CFG_USE_SEMAPHORES && CH_CFG_USE_SEMAPHORES_PRIORITY) | \
(CH_CFG_USE_MESSAGES && CH_CFG_USE_MESSAGES_PRIORITY)
#if CH_CFG_USE_MUTEXES
case CH_STATE_WTMTX:
#endif
#if CH_CFG_USE_CONDVARS
case CH_STATE_WTCOND:
#endif
#if CH_CFG_USE_SEMAPHORES && CH_CFG_USE_SEMAPHORES_PRIORITY
case CH_STATE_WTSEM:
#endif
#if CH_CFG_USE_MESSAGES && CH_CFG_USE_MESSAGES_PRIORITY
case CH_STATE_SNDMSGQ:
#endif
/* Re-enqueues tp with its new priority on the queue.*/
queue_prio_insert(queue_dequeue(tp),
(threads_queue_t *)tp->p_u.wtobjp);
break;
#endif
case CH_STATE_READY:
#if CH_DBG_ENABLE_ASSERTS
/* Prevents an assertion in chSchReadyI().*/
tp->p_state = CH_STATE_CURRENT;
#endif
/* Re-enqueues tp with its new priority on the ready list.*/
chSchReadyI(queue_dequeue(tp));
break;
}
/* Rescheduling.*/
chSchRescheduleS();
chSysUnlock();
return oldprio;
}
/**
* @brief Waits on the condition variable releasing the mutex lock.
* @details Releases the currently owned mutex, waits on the condition
* variable, and finally acquires the mutex again. All the sequence
* is performed atomically.
* @pre The invoking thread <b>must</b> have at least one owned mutex.
* @pre The configuration option @p CH_CFG_USE_CONDVARS_TIMEOUT must be enabled
* in order to use this function.
* @post Exiting the function because a timeout does not re-acquire the
* mutex, the mutex ownership is lost.
*
* @param[in] cp pointer to the @p condition_variable_t structure
* @param[in] time the number of ticks before the operation timeouts, the
* special values are handled as follow:
* - @a TIME_INFINITE no timeout.
* - @a TIME_IMMEDIATE this value is not allowed.
* .
* @return A message specifying how the invoking thread has been
* released from the condition variable.
* @retval MSG_OK if the condition variable has been signaled using
* @p chCondSignal().
* @retval MSG_RESET if the condition variable has been signaled using
* @p chCondBroadcast().
* @retval MSG_TIMEOUT if the condition variable has not been signaled within
* the specified timeout.
*
* @sclass
*/
msg_t chCondWaitTimeoutS(condition_variable_t *cp, systime_t time) {
mutex_t *mp;
msg_t msg;
chDbgCheckClassS();
chDbgCheck((cp != NULL) && (time != TIME_IMMEDIATE));
chDbgAssert(currp->p_mtxlist != NULL, "not owning a mutex");
mp = chMtxGetNextMutexS();
chMtxUnlockS(mp);
currp->p_u.wtobjp = cp;
queue_prio_insert(currp, &cp->c_queue);
msg = chSchGoSleepTimeoutS(CH_STATE_WTCOND, time);
if (msg != MSG_TIMEOUT)
chMtxLockS(mp);
return msg;
}
/**
* @brief Waits on the condition variable releasing the mutex lock.
* @details Releases the currently owned mutex, waits on the condition
* variable, and finally acquires the mutex again. All the sequence
* is performed atomically.
* @pre The invoking thread <b>must</b> have at least one owned mutex.
*
* @param[in] cp pointer to the @p condition_variable_t structure
* @return A message specifying how the invoking thread has been
* released from the condition variable.
* @retval MSG_OK if the condition variable has been signaled using
* @p chCondSignal().
* @retval MSG_RESET if the condition variable has been signaled using
* @p chCondBroadcast().
*
* @sclass
*/
msg_t chCondWaitS(condition_variable_t *cp) {
thread_t *ctp = currp;
mutex_t *mp;
msg_t msg;
chDbgCheckClassS();
chDbgCheck(cp != NULL);
chDbgAssert(ctp->p_mtxlist != NULL, "not owning a mutex");
mp = chMtxGetNextMutexS();
chMtxUnlockS(mp);
ctp->p_u.wtobjp = cp;
queue_prio_insert(ctp, &cp->c_queue);
chSchGoSleepS(CH_STATE_WTCOND);
msg = ctp->p_u.rdymsg;
chMtxLockS(mp);
return msg;
}
/**
* @brief Waits on the condition variable releasing the mutex lock.
* @details Releases the currently owned mutex, waits on the condition
* variable, and finally acquires the mutex again. All the sequence
* is performed atomically.
* @pre The invoking thread <b>must</b> have at least one owned mutex.
* @pre The configuration option @p CH_CFG_USE_CONDVARS_TIMEOUT must be enabled
* in order to use this function.
* @post Exiting the function because a timeout does not re-acquire the
* mutex, the mutex ownership is lost.
*
* @param[in] cp pointer to the @p condition_variable_t structure
* @param[in] time the number of ticks before the operation timeouts, the
* special values are handled as follow:
* - @a TIME_INFINITE no timeout.
* - @a TIME_IMMEDIATE this value is not allowed.
* .
* @return A message specifying how the invoking thread has been
* released from the condition variable.
* @retval MSG_OK if the condition variable has been signaled using
* @p chCondSignal().
* @retval MSG_RESET if the condition variable has been signaled using
* @p chCondBroadcast().
* @retval MSG_TIMEOUT if the condition variable has not been signaled within
* the specified timeout.
*
* @sclass
*/
msg_t chCondWaitTimeoutS(condition_variable_t *cp, systime_t time) {
mutex_t *mp;
msg_t msg;
chDbgCheckClassS();
chDbgCheck((cp != NULL) && (time != TIME_IMMEDIATE));
chDbgAssert(currp->p_mtxlist != NULL, "not owning a mutex");
/* Getting "current" mutex and releasing it.*/
mp = chMtxGetNextMutexS();
chMtxUnlockS(mp);
/* Start waiting on the condition variable, on exit the mutex is taken
again.*/
currp->p_u.wtobjp = cp;
queue_prio_insert(currp, &cp->c_queue);
msg = chSchGoSleepTimeoutS(CH_STATE_WTCOND, time);
if (msg != MSG_TIMEOUT) {
chMtxLockS(mp);
}
return msg;
}
/**
* @brief Waits on the condition variable releasing the mutex lock.
* @details Releases the currently owned mutex, waits on the condition
* variable, and finally acquires the mutex again. All the sequence
* is performed atomically.
* @pre The invoking thread <b>must</b> have at least one owned mutex.
*
* @param[in] cp pointer to the @p condition_variable_t structure
* @return A message specifying how the invoking thread has been
* released from the condition variable.
* @retval MSG_OK if the condition variable has been signaled using
* @p chCondSignal().
* @retval MSG_RESET if the condition variable has been signaled using
* @p chCondBroadcast().
*
* @sclass
*/
msg_t chCondWaitS(condition_variable_t *cp) {
thread_t *ctp = currp;
mutex_t *mp;
msg_t msg;
chDbgCheckClassS();
chDbgCheck(cp != NULL);
chDbgAssert(ctp->p_mtxlist != NULL, "not owning a mutex");
/* Getting "current" mutex and releasing it.*/
mp = chMtxGetNextMutexS();
chMtxUnlockS(mp);
/* Start waiting on the condition variable, on exit the mutex is taken
again.*/
ctp->p_u.wtobjp = cp;
queue_prio_insert(ctp, &cp->c_queue);
chSchGoSleepS(CH_STATE_WTCOND);
msg = ctp->p_u.rdymsg;
chMtxLockS(mp);
return msg;
}
/**
* @brief Locks the specified mutex.
* @post The mutex is locked and inserted in the per-thread stack of owned
* mutexes.
*
* @param[in] mp pointer to the @p mutex_t structure
*
* @sclass
*/
void chMtxLockS(mutex_t *mp) {
thread_t *ctp = currp;
chDbgCheckClassS();
chDbgCheck(mp != NULL);
/* Is the mutex already locked? */
if (mp->m_owner != NULL) {
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
chDbgAssert(mp->m_cnt >= (cnt_t)1, "counter is not positive");
/* If the mutex is already owned by this thread, the counter is increased
and there is no need of more actions.*/
if (mp->m_owner == ctp) {
mp->m_cnt++;
}
else {
#endif
/* Priority inheritance protocol; explores the thread-mutex dependencies
boosting the priority of all the affected threads to equal the
priority of the running thread requesting the mutex.*/
thread_t *tp = mp->m_owner;
/* Does the running thread have higher priority than the mutex
owning thread? */
while (tp->p_prio < ctp->p_prio) {
/* Make priority of thread tp match the running thread's priority.*/
tp->p_prio = ctp->p_prio;
/* The following states need priority queues reordering.*/
switch (tp->p_state) {
case CH_STATE_WTMTX:
/* Re-enqueues the mutex owner with its new priority.*/
queue_prio_insert(queue_dequeue(tp), &tp->p_u.wtmtxp->m_queue);
tp = tp->p_u.wtmtxp->m_owner;
/*lint -e{9042} [16.1] Continues the while.*/
continue;
#if (CH_CFG_USE_CONDVARS == TRUE) || \
((CH_CFG_USE_SEMAPHORES == TRUE) && \
(CH_CFG_USE_SEMAPHORES_PRIORITY == TRUE)) || \
((CH_CFG_USE_MESSAGES == TRUE) && \
(CH_CFG_USE_MESSAGES_PRIORITY == TRUE))
#if CH_CFG_USE_CONDVARS == TRUE
case CH_STATE_WTCOND:
#endif
#if (CH_CFG_USE_SEMAPHORES == TRUE) && \
(CH_CFG_USE_SEMAPHORES_PRIORITY == TRUE)
case CH_STATE_WTSEM:
#endif
#if (CH_CFG_USE_MESSAGES == TRUE) && (CH_CFG_USE_MESSAGES_PRIORITY == TRUE)
case CH_STATE_SNDMSGQ:
#endif
/* Re-enqueues tp with its new priority on the queue.*/
queue_prio_insert(queue_dequeue(tp), &tp->p_u.wtmtxp->m_queue);
break;
#endif
case CH_STATE_READY:
#if CH_DBG_ENABLE_ASSERTS == TRUE
/* Prevents an assertion in chSchReadyI().*/
tp->p_state = CH_STATE_CURRENT;
#endif
/* Re-enqueues tp with its new priority on the ready list.*/
(void) chSchReadyI(queue_dequeue(tp));
break;
default:
/* Nothing to do for other states.*/
break;
}
break;
}
/* Sleep on the mutex.*/
queue_prio_insert(ctp, &mp->m_queue);
ctp->p_u.wtmtxp = mp;
chSchGoSleepS(CH_STATE_WTMTX);
/* It is assumed that the thread performing the unlock operation assigns
the mutex to this thread.*/
chDbgAssert(mp->m_owner == ctp, "not owner");
chDbgAssert(ctp->p_mtxlist == mp, "not owned");
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
chDbgAssert(mp->m_cnt == (cnt_t)1, "counter is not one");
}
#endif
}
else {
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
chDbgAssert(mp->m_cnt == (cnt_t)0, "counter is not zero");
mp->m_cnt++;
#endif
/* It was not owned, inserted in the owned mutexes list.*/
mp->m_owner = ctp;
mp->m_next = ctp->p_mtxlist;
ctp->p_mtxlist = mp;
}
}
