void condvar_wait(struct condvar *cv, struct mutex *m)
{
uint32_t old_itr_status;
struct wait_queue_elem wqe;
old_itr_status = thread_mask_exceptions(THREAD_EXCP_ALL);
/* Link this condvar to this mutex until reinitialized */
cpu_spin_lock(&cv->spin_lock);
TEE_ASSERT(!cv->m || cv->m == m);
cv->m = m;
cpu_spin_unlock(&cv->spin_lock);
cpu_spin_lock(&m->spin_lock);
/* Add to mutex wait queue as a condvar waiter */
wq_wait_init_condvar(&m->wq, &wqe, cv);
/* Unlock the mutex */
TEE_ASSERT(m->value == MUTEX_VALUE_LOCKED);
thread_rem_mutex(m);
m->value = MUTEX_VALUE_UNLOCKED;
cpu_spin_unlock(&m->spin_lock);
thread_unmask_exceptions(old_itr_status);
/* Wake eventual waiters */
wq_wake_one(&m->wq);
wq_wait_final(&m->wq, &wqe);
mutex_lock(m);
}
static void cv_signal(struct condvar *cv, bool only_one)
{
uint32_t old_itr_status;
struct mutex *m;
old_itr_status = thread_mask_exceptions(THREAD_EXCP_ALL);
cpu_spin_lock(&cv->spin_lock);
m = cv->m;
cpu_spin_unlock(&cv->spin_lock);
thread_unmask_exceptions(old_itr_status);
if (m)
wq_promote_condvar(&m->wq, cv, only_one);
}
void mutex_unlock(struct mutex *m)
{
uint32_t old_itr_status;
old_itr_status = thread_mask_exceptions(THREAD_EXCP_ALL);
cpu_spin_lock(&m->spin_lock);
TEE_ASSERT(m->value == MUTEX_VALUE_LOCKED);
thread_rem_mutex(m);
m->value = MUTEX_VALUE_UNLOCKED;
cpu_spin_unlock(&m->spin_lock);
thread_unmask_exceptions(old_itr_status);
wq_wake_one(&m->wq);
}
bool mutex_trylock(struct mutex *m)
{
uint32_t old_itr_status;
enum mutex_value old_value;
old_itr_status = thread_mask_exceptions(THREAD_EXCP_ALL);
cpu_spin_lock(&m->spin_lock);
old_value = m->value;
if (old_value == MUTEX_VALUE_UNLOCKED) {
m->value = MUTEX_VALUE_LOCKED;
thread_add_mutex(m);
}
cpu_spin_unlock(&m->spin_lock);
thread_unmask_exceptions(old_itr_status);
return old_value == MUTEX_VALUE_UNLOCKED;
}
void mutex_lock(struct mutex *m)
{
while (true) {
uint32_t old_itr_status;
enum mutex_value old_value;
struct wait_queue_elem wqe;
/*
* If the mutex is locked we need to initialize the wqe
* before releasing the spinlock to guarantee that we don't
* miss the wakeup from mutex_unlock().
*
* If the mutex is unlocked we don't need to use the wqe at
* all.
*/
old_itr_status = thread_mask_exceptions(THREAD_EXCP_ALL);
cpu_spin_lock(&m->spin_lock);
old_value = m->value;
if (old_value == MUTEX_VALUE_LOCKED) {
wq_wait_init(&m->wq, &wqe);
} else {
m->value = MUTEX_VALUE_LOCKED;
thread_add_mutex(m);
}
cpu_spin_unlock(&m->spin_lock);
thread_unmask_exceptions(old_itr_status);
if (old_value == MUTEX_VALUE_LOCKED) {
/*
* Someone else is holding the lock, wait in normal
* world for the lock to become available.
*/
wq_wait_final(&m->wq, &wqe);
} else
return;
}
}
static void lock_global(void)
{
cpu_spin_lock(&thread_global_lock);
}
void tee_l2cc_mutex_lock(void)
{
if (l2cc_mutex)
cpu_spin_lock(l2cc_mutex);
}
