/**
* @brief Unlocks the specified mutex.
* @note Mutexes must be unlocked in reverse lock order. Violating this
* rules will result in a panic if assertions are enabled.
* @pre The invoking thread <b>must</b> have at least one owned mutex.
* @post The mutex is unlocked and removed from the per-thread stack of
* owned mutexes.
* @post This function does not reschedule so a call to a rescheduling
* function must be performed before unlocking the kernel.
*
* @param[in] mp pointer to the @p mutex_t structure
*
* @sclass
*/
void chMtxUnlockS(mutex_t *mp) {
thread_t *ctp = currp;
mutex_t *lmp;
chDbgCheckClassS();
chDbgCheck(mp != NULL);
chDbgAssert(ctp->p_mtxlist != NULL, "owned mutexes list empty");
chDbgAssert(ctp->p_mtxlist->m_owner == ctp, "ownership failure");
#if CH_CFG_USE_MUTEXES_RECURSIVE
chDbgAssert(mp->m_cnt >= 1, "counter is not positive");
if (--mp->m_cnt == 0) {
#endif
chDbgAssert(ctp->p_mtxlist == mp, "not next in list");
/* Removes the top mutex from the thread's owned mutexes list and marks
it as not owned. Note, it is assumed to be the same mutex passed as
parameter of this function.*/
ctp->p_mtxlist = mp->m_next;
/* If a thread is waiting on the mutex then the fun part begins.*/
if (chMtxQueueNotEmptyS(mp)) {
thread_t *tp;
/* Recalculates the optimal thread priority by scanning the owned
mutexes list.*/
tprio_t newprio = ctp->p_realprio;
lmp = ctp->p_mtxlist;
while (lmp != NULL) {
/* If the highest priority thread waiting in the mutexes list has a
greater priority than the current thread base priority then the
final priority will have at least that priority.*/
if (chMtxQueueNotEmptyS(lmp) && (lmp->m_queue.p_next->p_prio > newprio))
newprio = lmp->m_queue.p_next->p_prio;
lmp = lmp->m_next;
}
/* Assigns to the current thread the highest priority among all the
waiting threads.*/
ctp->p_prio = newprio;
/* Awakens the highest priority thread waiting for the unlocked mutex and
assigns the mutex to it.*/
#if CH_CFG_USE_MUTEXES_RECURSIVE
mp->m_cnt = 1;
#endif
tp = queue_fifo_remove(&mp->m_queue);
mp->m_owner = tp;
mp->m_next = tp->p_mtxlist;
tp->p_mtxlist = mp;
chSchReadyI(tp);
}
else
mp->m_owner = NULL;
#if CH_CFG_USE_MUTEXES_RECURSIVE
}
#endif
}
/**
* @brief Unlocks all mutexes owned by the invoking thread.
* @post The stack of owned mutexes is emptied and all the found
* mutexes are unlocked.
* @note This function is <b>MUCH MORE</b> efficient than releasing the
* mutexes one by one and not just because the call overhead,
* this function does not have any overhead related to the priority
* inheritance mechanism.
*
* @api
*/
void chMtxUnlockAll(void) {
thread_t *ctp = currp;
chSysLock();
if (ctp->p_mtxlist != NULL) {
do {
mutex_t *mp = ctp->p_mtxlist;
ctp->p_mtxlist = mp->m_next;
if (chMtxQueueNotEmptyS(mp)) {
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
mp->m_cnt = (cnt_t)1;
#endif
thread_t *tp = queue_fifo_remove(&mp->m_queue);
mp->m_owner = tp;
mp->m_next = tp->p_mtxlist;
tp->p_mtxlist = mp;
(void) chSchReadyI(tp);
}
else {
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
mp->m_cnt = (cnt_t)0;
#endif
mp->m_owner = NULL;
}
} while (ctp->p_mtxlist != NULL);
ctp->p_prio = ctp->p_realprio;
chSchRescheduleS();
}
chSysUnlock();
}
/**
* @brief Unlocks all mutexes owned by the invoking thread.
* @post The stack of owned mutexes is emptied and all the found
* mutexes are unlocked.
* @post This function does not reschedule so a call to a rescheduling
* function must be performed before unlocking the kernel.
* @note This function is <b>MUCH MORE</b> efficient than releasing the
* mutexes one by one and not just because the call overhead,
* this function does not have any overhead related to the priority
* inheritance mechanism.
*
* @sclass
*/
void chMtxUnlockAllS(void) {
thread_t *ctp = currp;
while (ctp->mtxlist != NULL) {
mutex_t *mp = ctp->mtxlist;
ctp->mtxlist = mp->next;
if (chMtxQueueNotEmptyS(mp)) {
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
mp->cnt = (cnt_t)1;
#endif
thread_t *tp = queue_fifo_remove(&mp->queue);
mp->owner = tp;
mp->next = tp->mtxlist;
tp->mtxlist = mp;
(void) chSchReadyI(tp);
}
else {
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
mp->cnt = (cnt_t)0;
#endif
mp->owner = NULL;
}
}
ctp->prio = ctp->realprio;
}
/**
* @brief Unlocks the next owned mutex in reverse lock order.
* @pre The invoking thread <b>must</b> have at least one owned mutex.
* @post The mutex is unlocked and removed from the per-thread stack of
* owned mutexes.
*
* @return A pointer to the unlocked mutex.
*
* @api
*/
Mutex *chMtxUnlock(void) {
Thread *ctp = currp;
Mutex *ump, *mp;
chSysLock();
chDbgAssert(ctp->p_mtxlist != NULL,
"chMtxUnlock(), #1",
"owned mutexes list empty");
chDbgAssert(ctp->p_mtxlist->m_owner == ctp,
"chMtxUnlock(), #2",
"ownership failure");
/* Removes the top Mutex from the Thread's owned mutexes list and marks it
as not owned.*/
ump = ctp->p_mtxlist;
ctp->p_mtxlist = ump->m_next;
/* If a thread is waiting on the mutex then the fun part begins.*/
if (chMtxQueueNotEmptyS(ump)) {
Thread *tp;
/* Recalculates the optimal thread priority by scanning the owned
mutexes list.*/
tprio_t newprio = ctp->p_realprio;
mp = ctp->p_mtxlist;
while (mp != NULL) {
/* If the highest priority thread waiting in the mutexes list has a
greater priority than the current thread base priority then the final
priority will have at least that priority.*/
if (chMtxQueueNotEmptyS(mp) && (mp->m_queue.p_next->p_prio > newprio))
newprio = mp->m_queue.p_next->p_prio;
mp = mp->m_next;
}
/* Assigns to the current thread the highest priority among all the
waiting threads.*/
ctp->p_prio = newprio;
/* Awakens the highest priority thread waiting for the unlocked mutex and
assigns the mutex to it.*/
tp = fifo_remove(&ump->m_queue);
ump->m_owner = tp;
ump->m_next = tp->p_mtxlist;
tp->p_mtxlist = ump;
chSchWakeupS(tp, RDY_OK);
}
else
ump->m_owner = NULL;
chSysUnlock();
return ump;
}
/**
* @brief Unlocks all the mutexes owned by the invoking thread.
* @post The stack of owned mutexes is emptied and all the found
* mutexes are unlocked.
* @note This function is <b>MUCH MORE</b> efficient than releasing the
* mutexes one by one and not just because the call overhead,
* this function does not have any overhead related to the priority
* inheritance mechanism.
*
* @api
*/
void chMtxUnlockAll(void) {
Thread *ctp = currp;
chSysLock();
if (ctp->p_mtxlist != NULL) {
do {
Mutex *ump = ctp->p_mtxlist;
ctp->p_mtxlist = ump->m_next;
if (chMtxQueueNotEmptyS(ump)) {
Thread *tp = fifo_remove(&ump->m_queue);
ump->m_owner = tp;
ump->m_next = tp->p_mtxlist;
tp->p_mtxlist = ump;
chSchReadyI(tp);
}
else
ump->m_owner = NULL;
} while (ctp->p_mtxlist != NULL);
ctp->p_prio = ctp->p_realprio;
chSchRescheduleS();
}
chSysUnlock();
}
/**
* @brief Unlocks the specified mutex.
* @note Mutexes must be unlocked in reverse lock order. Violating this
* rules will result in a panic if assertions are enabled.
* @pre The invoking thread <b>must</b> have at least one owned mutex.
* @post The mutex is unlocked and removed from the per-thread stack of
* owned mutexes.
*
* @param[in] mp pointer to the @p mutex_t structure
*
* @api
*/
void chMtxUnlock(mutex_t *mp) {
thread_t *ctp = currp;
mutex_t *lmp;
chDbgCheck(mp != NULL);
chSysLock();
chDbgAssert(ctp->mtxlist != NULL, "owned mutexes list empty");
chDbgAssert(ctp->mtxlist->owner == ctp, "ownership failure");
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
chDbgAssert(mp->cnt >= (cnt_t)1, "counter is not positive");
if (--mp->cnt == (cnt_t)0) {
#endif
chDbgAssert(ctp->mtxlist == mp, "not next in list");
/* Removes the top mutex from the thread's owned mutexes list and marks
it as not owned. Note, it is assumed to be the same mutex passed as
parameter of this function.*/
ctp->mtxlist = mp->next;
/* If a thread is waiting on the mutex then the fun part begins.*/
if (chMtxQueueNotEmptyS(mp)) {
thread_t *tp;
/* Recalculates the optimal thread priority by scanning the owned
mutexes list.*/
tprio_t newprio = ctp->realprio;
lmp = ctp->mtxlist;
while (lmp != NULL) {
/* If the highest priority thread waiting in the mutexes list has a
greater priority than the current thread base priority then the
final priority will have at least that priority.*/
if (chMtxQueueNotEmptyS(lmp) &&
(lmp->queue.next->prio > newprio)) {
newprio = lmp->queue.next->prio;
}
lmp = lmp->next;
}
/* Assigns to the current thread the highest priority among all the
waiting threads.*/
ctp->prio = newprio;
/* Awakens the highest priority thread waiting for the unlocked mutex and
assigns the mutex to it.*/
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
mp->cnt = (cnt_t)1;
#endif
tp = queue_fifo_remove(&mp->queue);
mp->owner = tp;
mp->next = tp->mtxlist;
tp->mtxlist = mp;
/* Note, not using chSchWakeupS() becuase that function expects the
current thread to have the higher or equal priority than the ones
in the ready list. This is not necessarily true here because we
just changed priority.*/
(void) chSchReadyI(tp);
chSchRescheduleS();
}
else {
mp->owner = NULL;
}
#if CH_CFG_USE_MUTEXES_RECURSIVE == TRUE
}
#endif
chSysUnlock();
}
