/*
* Unlock the given lock
*/
void lock_release(lock_t *lock) {
/* Check if lock was in fact locked */
if (lock->state == LOCK_LOCKED) {
/* Open lock and wake up the process waiting for the lock */
lock->state = LOCK_OPEN;
sleepq_wake(lock);
}
}
void lock_release( lock_t *lock ) {
interrupt_status_t intr_status;
intr_status = _interrupt_disable();
spinlock_acquire(&lock->slock);
lock->locked = LOCK_UNLOCKED;
sleepq_wake(lock);
spinlock_release(&lock->slock);
_interrupt_set_state(intr_status);
}
void lock_release(lock_t *lock){
interrupt_status_t intr_status;
intr_status = _interrupt_disable();
spinlock_acquire(&(lock->spinlock));
/* We unlock the lock and wake the next thread in the queue */
lock->locked = 0;
sleepq_wake(lock);
spinlock_release(&(lock->spinlock));
_interrupt_set_state(intr_status);
}
/* For the signal function, we simply wake the the next thread waiting */
void condition_signal(cond_t *cond, lock_t *condition_lock){
interrupt_status_t intr_status;
intr_status = _interrupt_disable();
spinlock_acquire(&(cond->spinlock));
lock_acquire(condition_lock);
sleepq_wake(cond);
lock_release(condition_lock);
spinlock_release(&(cond->spinlock));
}
int usr_sem_vacate(usr_sem_t* sem) {
interrupt_status_t intr_status;
intr_status = _interrupt_disable();
spinlock_acquire(&(sem->sem_slock));
sem->value++;
if (sem->value <= 0) {
sleepq_wake(&(sem->value));
}
spinlock_release(&(sem->sem_slock));
_interrupt_set_state(intr_status);
return 0;
}
void semaphore_V(semaphore_t *sem)
{
interrupt_status_t intr_status;
intr_status = _interrupt_disable();
spinlock_acquire(&sem->slock);
sem->value++;
if (sem->value <= 0) {
sleepq_wake(sem);
}
spinlock_release(&sem->slock);
_interrupt_set_state(intr_status);
}
/*
* Unlock the given lock
*/
void lock_release(lock_t *lock) {
interrupt_status_t intr_status;
intr_status = _interrupt_disable();
spinlock_acquire(&lock->spinlock); // Acquire spinlock
/* Check if lock was in fact locked */
if (lock->state == LOCK_LOCKED) {
/* Open lock and wake up the process waiting for the lock */
lock->state = LOCK_OPEN;
sleepq_wake(lock);
}
spinlock_release(&lock->spinlock);
_interrupt_set_state(intr_status);
}
void finish_given_process(process_id_t pid, int retval)
{
process_id_t parent = process_table[pid].parent;
process_id_t zombie;
process_table[pid].retval = retval;
while ((zombie = process_table[pid].first_zombie) >= 0) {
/* We have zombie children - remove them. */
process_table[zombie].state = PROCESS_FREE;
process_table[zombie].retval = -1;
process_table[zombie].parent = -1;
process_table[pid].first_zombie = process_table[zombie].next_zombie;
process_table[pid].children--;
}
if (parent >= 0
&& process_table[parent].state == PROCESS_ZOMBIE) {
/* We have a zombie parent, implying we can never be
joined. */
if (--(process_table[parent].children) == 0
&& process_table[parent].retval < 0) {
/* Oh, and our parent is joined and we are the last
child. so free our parent. */
finish_given_process(parent, 0);
}
process_table[pid].state = PROCESS_FREE;
} else if (parent >= 0) {
/* Our parent is alive and well, add us to its list of zombies */
process_table[pid].state = PROCESS_ZOMBIE;
zombie = process_table[parent].first_zombie;
process_table[pid].next_zombie = zombie;
if (zombie >= 0) {
process_table[zombie].prev_zombie = pid;
}
process_table[parent].first_zombie = pid;
} else {
/* We have no parent, i.e. we are the initial program, and
will be joined by the startup thread in init/main.c */
process_table[pid].state = PROCESS_ZOMBIE;
}
sleepq_wake(&process_table[pid]);
}
/**
* Terminates the current process and sets a return value
*/
void process_finish(uint32_t retval) {
interrupt_status_t intr_status;
process_id_t pid;
thread_table_t *my_thread;
// Find out who we are.
pid = process_get_current_process();
my_thread = thread_get_current_thread_entry();
// Ensure that we're the only ones touching the process table.
intr_status = _interrupt_disable();
spinlock_acquire(&process_table_slock);
// Mark the stack as free so new threads can reuse it.
process_free_stack(my_thread);
if(--process_table[pid].threads == 0) {
// Last thread in process; now we die.
// Mark ourself as dying.
process_table[pid].retval = retval;
process_table[pid].state = PROCESS_DYING;
vm_destroy_pagetable(my_thread->pagetable);
// Wake whomever may be sleeping for the process
sleepq_wake(&process_table[pid]);
}
// Free our locks.
spinlock_release(&process_table_slock);
_interrupt_set_state(intr_status);
my_thread->pagetable = NULL;
// Kill the thread.
thread_finish();
}
/*
* Signal next thread waiting for the given condition
*/
void condition_signal(cond_t *cond, lock_t *condition_lock) {
condition_lock = condition_lock;
sleepq_wake(cond); // Wake up next waiting thread
}
void condition_signal (cond_t *cond, lock_t *lock ) {
lock = lock;
sleepq_wake(cond);
}
void condition_signal(cond_t *cond, lock_t *condition_lock)
{
sleepq_wake(cond); // flyt en proces fra q til e
}
/*
* callout_softclock:
*
* Soft interrupt handler, scheduled above if there is work to
* be done. Callouts are made in soft interrupt context.
*/
static void
callout_softclock(void *v)
{
callout_impl_t *c;
struct callout_cpu *cc;
void (*func)(void *);
void *arg;
int mpsafe, count, ticks, delta;
lwp_t *l;
l = curlwp;
KASSERT(l->l_cpu == curcpu());
cc = l->l_cpu->ci_data.cpu_callout;
mutex_spin_enter(cc->cc_lock);
cc->cc_lwp = l;
while (!CIRCQ_EMPTY(&cc->cc_todo)) {
c = CIRCQ_FIRST(&cc->cc_todo);
KASSERT(c->c_magic == CALLOUT_MAGIC);
KASSERT(c->c_func != NULL);
KASSERT(c->c_cpu == cc);
KASSERT((c->c_flags & CALLOUT_PENDING) != 0);
KASSERT((c->c_flags & CALLOUT_FIRED) == 0);
CIRCQ_REMOVE(&c->c_list);
/* If due run it, otherwise insert it into the right bucket. */
ticks = cc->cc_ticks;
delta = c->c_time - ticks;
if (delta > 0) {
CIRCQ_INSERT(&c->c_list, BUCKET(cc, delta, c->c_time));
continue;
}
if (delta < 0)
cc->cc_ev_late.ev_count++;
c->c_flags = (c->c_flags & ~CALLOUT_PENDING) |
(CALLOUT_FIRED | CALLOUT_INVOKING);
mpsafe = (c->c_flags & CALLOUT_MPSAFE);
func = c->c_func;
arg = c->c_arg;
cc->cc_active = c;
mutex_spin_exit(cc->cc_lock);
KASSERT(func != NULL);
if (__predict_false(!mpsafe)) {
KERNEL_LOCK(1, NULL);
(*func)(arg);
KERNEL_UNLOCK_ONE(NULL);
} else
(*func)(arg);
mutex_spin_enter(cc->cc_lock);
/*
* We can't touch 'c' here because it might be
* freed already. If LWPs waiting for callout
* to complete, awaken them.
*/
cc->cc_active = NULL;
if ((count = cc->cc_nwait) != 0) {
cc->cc_nwait = 0;
/* sleepq_wake() drops the lock. */
sleepq_wake(&cc->cc_sleepq, cc, count, cc->cc_lock);
mutex_spin_enter(cc->cc_lock);
}
}
cc->cc_lwp = NULL;
mutex_spin_exit(cc->cc_lock);
}