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#include <globals.h>
#include <drivers/uart.h>
#include <sys/schedule.h>
#include <util/mutex.h>
extern void kernel_usr_task_loop(void);
extern void cleanup(void);
void init_scheduler(void)
{
// Set rthread to usrloopthread - an infinitely running thread so that the pointer will never be null
usrloopthread.pc = (void*)kernel_usr_task_loop;
usrloopthread.sp = (void*)0x5FC8;
*(unsigned long**)usrloopthread.sp = (unsigned long*)kernel_usr_task_loop;
usrloopthread.sp_base = (void*)0x6000;
usrloopthread.mptr = 0;
usrloopthread.pid = -1;
usrloopthread.priority = -1;
usrloopthread.status = THREAD_READY;
scheduler.rthread = &usrloopthread;
// Initialize Rotating Buffers
struct ThreadQueues* tq;
for (int i = 0; i < PRIORITIES; i++) {
tq = &scheduler.thread_queues[i];
struct ThreadRotBuffer* trb = &tq->ready;
for (int i = 0; i < TQUEUE_CNT; i++) {
trb->roffset = 0;
trb->woffset = 0;
for (int j = 0; j < TQUEUE_MAX; j++)
trb->queue[j] = 0;
trb += 1;
}
}
// Initialize nextpid
nextpid = SCHED_PID + 1;
}
void* get_stack(void)
{
for (int i = 0; i < MAX_THREADS; i++) {
if (stacks_table[i] == 0) {
stacks_table[i] = 1;
return (void*)0x20000000 - STACK_SIZE*i;
}
}
return 0;
}
void add_thread(void* pc, void* arg, unsigned char priority)
{
void* sp = get_stack();
struct Thread* thread = (struct Thread*)malloca(sizeof(struct Thread), 4);
thread->pc = pc;
if (sp) {
thread->sp_base = sp;
unsigned long* argp = sp;
argp -= 1;
*argp = (unsigned long)arg; // Set r0 to the argument
argp -= 13;
*(unsigned long**)argp = (unsigned long*)cleanup; // Set lr to the cleanup function
thread->sp = (void*)argp;
thread->status = THREAD_READY;
} else {
thread->sp_base = 0;
thread->sp = 0;
thread->status = THREAD_SERROR;
}
thread->mptr = (void*)0;
thread->pid = nextpid++;
thread->priority = priority % PRIORITIES;
thread->preempt = 0;
// Add Thread* to scheduler's appropriate buffer
struct ThreadQueues* tq = &scheduler.thread_queues[thread->priority];
struct ThreadRotBuffer* trb;
if (thread->status == THREAD_SERROR) {
trb = &tq->serror;
} else {
trb = &tq->ready;
}
trb->queue[trb->woffset++] = thread;
trb->woffset %= TQUEUE_MAX;
}
void uart_scheduler(void)
{
uart_string("Scheduler Info\n==============\nCurrent\n");
uart_hex((unsigned long)scheduler.rthread);
uart_char(' ');
memshow32((void*)scheduler.rthread, 6);
struct ThreadQueues* tq;
for(int p = 0; p < PRIORITIES; p++) {
uart_string("Priority ");
uart_10(p);
uart_char('\n');
tq = &scheduler.thread_queues[p];
struct ThreadRotBuffer* trb;
trb = &tq->ready;
for(int i = 0; i < TQUEUE_CNT; i++) {
if (trb->roffset == trb->woffset) {
trb += 1;
continue;
}
uart_string("Queue ");
uart_10(i);
uart_char('\n');
unsigned long roffset = trb->roffset;
while (roffset != trb->woffset) {
uart_hex((unsigned long)trb->queue[roffset]);
uart_char(' ');
memshow32((void*)trb->queue[roffset], 6);
//memshow32((void*)trb->queue[roffset]->sp, 14);
roffset++;
roffset %= TQUEUE_MAX;
}
trb += 1;
}
}
uart_string("==============\n");
}
struct Thread* next_thread(void)
{
struct Thread* next = &usrloopthread;
for (int p = 0; p < PRIORITIES; p++) {
struct ThreadRotBuffer* rb = &scheduler.thread_queues[p].ready;
if (rb->roffset == rb->woffset)
continue;
return rb->queue[rb->roffset];
}
return next;
}
void* get_rthread_roffset(void)
{
return &scheduler.thread_queues[scheduler.rthread->priority].ready.roffset;
}
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