/*
* Find the best (highest priority) thread in given
* thread queue. Returns null if queue is empty.
*/
static __inline__ struct Kernel_Thread* Find_Best(struct Thread_Queue* queue)
{
/* Pick the highest priority thread */
struct Kernel_Thread *kthread = queue->head, *best = 0;
while (kthread != 0) {
if (best == 0 || kthread->priority > best->priority)
best = kthread;
kthread = Get_Next_In_Thread_Queue(kthread);
}
return best;
}
void Switch_To_MLF(void)
{
struct Kernel_Thread *kthread;
kthread = s_runQueue->head;
// Transition to MLF
MAX_QUEUE_LEVEL = 4;
while (kthread != 0) {
if (kthread->priority == PRIORITY_IDLE)
{
Remove_From_Thread_Queue(&s_runQueue ,kthread);
Add_To_Front_Of_Thread_Queue(&s_runQueue[MAX_QUEUE_LEVEL-1], kthread);
kthread->currentReadyQueue = MAX_QUEUE_LEVEL-1;
}
kthread = Get_Next_In_Thread_Queue(kthread);
}
}
/*
* Wake up all threads waiting on given wait queue.
* Must be called with interrupts disabled!
* See Keyboard_Interrupt_Handler() function in keyboard.c
* for an example.
*/
void Wake_Up(struct Thread_Queue* waitQueue)
{
struct Kernel_Thread *kthread = waitQueue->head, *next;
KASSERT(!Interrupts_Enabled());
/*
* Walk throught the list of threads in the wait queue,
* transferring each one to the run queue.
*/
while (kthread != 0) {
next = Get_Next_In_Thread_Queue(kthread);
Make_Runnable(kthread);
kthread = next;
}
/* The wait queue is now empty. */
Clear_Thread_Queue(waitQueue);
}
/*
* The reaper thread. Its job is to de-allocate memory
* used by threads which have finished.
*/
static void Reaper(ulong_t arg)
{
struct Kernel_Thread *kthread;
Disable_Interrupts();
while (true) {
/* See if there are any threads needing disposal. */
if ((kthread = s_graveyardQueue.head) == 0) {
/* Graveyard is empty, so wait for a thread to die. */
Wait(&s_reaperWaitQueue);
}
else {
/* Make the graveyard queue empty. */
Clear_Thread_Queue(&s_graveyardQueue);
/*
* Now we can re-enable interrupts, since we
* have removed all the threads needing disposal.
*/
Enable_Interrupts();
Yield(); /* allow other threads to run? */
/* Dispose of the dead threads. */
while (kthread != 0) {
struct Kernel_Thread* next = Get_Next_In_Thread_Queue(kthread);
#if 0
Print("Reaper: disposing of thread @ %x, stack @ %x\n",
kthread, kthread->stackPage);
#endif
Destroy_Thread(kthread);
kthread = next;
}
/*
* Disable interrupts again, since we're going to
* do another iteration.
*/
Disable_Interrupts();
}
}
}