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Diffstat (limited to 'kernel/sys/schedule.c')
-rw-r--r--kernel/sys/schedule.c96
1 files changed, 27 insertions, 69 deletions
diff --git a/kernel/sys/schedule.c b/kernel/sys/schedule.c
index 142ffaf..c8dc581 100644
--- a/kernel/sys/schedule.c
+++ b/kernel/sys/schedule.c
@@ -8,6 +8,7 @@
extern void kernel_usr_task_loop(void);
+/// Initialize the scheduler
void init_scheduler(void)
{
// Set rthread to usrloopthread - an infinitely running thread so that the pointer will never be null
@@ -27,26 +28,11 @@ void init_scheduler(void)
// Initialize Scheduling Queues
for (unsigned long p = 0; p < PRIORITIES; p++) {
// Ready Init
- scheduler.ready[p].start.value = 0;
- scheduler.ready[p].start.next = &scheduler.ready[p].end;
- scheduler.ready[p].start.entry_type = START_ENTRY;
- scheduler.ready[p].end.value = 0;
- scheduler.ready[p].end.next = &scheduler.ready[p].start;
- scheduler.ready[p].end.entry_type = END_ENTRY;
+ scheduler.ready[p].start.next = 0;
// Mutex Wait Init
- scheduler.mwait[p].start.value = 0;
- scheduler.mwait[p].start.next = &scheduler.mwait[p].end;
- scheduler.mwait[p].start.entry_type = START_ENTRY;
- scheduler.mwait[p].end.value = 0;
- scheduler.mwait[p].end.next = &scheduler.mwait[p].start;
- scheduler.mwait[p].end.entry_type = END_ENTRY;
+ scheduler.mwait[p].start.next = 0;
// Signal Wait Init
- scheduler.swait[p].start.value = 0;
- scheduler.swait[p].start.next = &scheduler.swait[p].end;
- scheduler.swait[p].start.entry_type = START_ENTRY;
- scheduler.swait[p].end.value = 0;
- scheduler.swait[p].end.next = &scheduler.swait[p].start;
- scheduler.swait[p].end.entry_type = END_ENTRY;
+ scheduler.swait[p].start.next = 0;
}
// Initialize nextpid
@@ -60,18 +46,13 @@ void init_scheduler(void)
t->highest_mutex = 0;
thread_entries[i].value = t;
thread_entries[i].next = &thread_entries[(i+1)];
- thread_entries[i].entry_type = VALUE_ENTRY;
}
// Initialize the free queue
- scheduler.free_threads.start.value = 0;
- scheduler.free_threads.start.entry_type = START_ENTRY;
- scheduler.free_threads.end.value = 0;
- scheduler.free_threads.end.entry_type = END_ENTRY;
scheduler.free_threads.start.next = &thread_entries[0];
- scheduler.free_threads.end.next = &thread_entries[MAX_THREADS-1];
- thread_entries[MAX_THREADS-1].next = &scheduler.free_threads.end;
+ thread_entries[MAX_THREADS-1].next = 0;
}
+/// Push the given thread to a given priority queue
void push_thread_to_queue(struct Thread* t, unsigned char type, unsigned char priority)
{
struct Entry* entry = &thread_entries[t->offset];
@@ -86,27 +67,9 @@ void push_thread_to_queue(struct Thread* t, unsigned char type, unsigned char pr
return;
}
push_to_queue(entry, queue);
- //queue->end.next->next = entry;
- //queue->end.next = entry;
- //entry->next = &queue->end;
-}
-
-void prepend_thread_to_queue(struct Thread* t, unsigned char type, unsigned char priority)
-{
- struct Entry* entry = &thread_entries[t->offset];
- struct Queue* queue;
- if (type == THREAD_READY) {
- queue = &scheduler.ready[priority];
- } else if (type == THREAD_MWAIT) {
- queue = &scheduler.mwait[priority];
- } else if (type == THREAD_SWAIT) {
- queue = &scheduler.swait[priority];
- } else {
- return;
- }
- prepend_to_queue(entry, queue);
}
+/// Get a thread from a queue
struct Entry* pop_thread_from_queue(unsigned char type, unsigned char priority)
{
struct Entry* entry = 0;
@@ -123,6 +86,7 @@ struct Entry* pop_thread_from_queue(unsigned char type, unsigned char priority)
return pop_from_queue(queue);
}
+/// Find thread with pid
struct Entry* find_pid(unsigned long pid)
{
for (unsigned char p = 0; p < PRIORITIES; p++) {
@@ -133,7 +97,7 @@ struct Entry* find_pid(unsigned long pid)
queue = &scheduler.ready[p];
prev = &queue->start;
entry = prev->next;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
if (((struct Thread*)entry->value)->pid == pid)
return prev;
prev = entry;
@@ -143,7 +107,7 @@ struct Entry* find_pid(unsigned long pid)
queue = &scheduler.mwait[p];
prev = &queue->start;
entry = prev->next;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
if (((struct Thread*)entry->value)->pid == pid)
return prev;
prev = entry;
@@ -153,7 +117,7 @@ struct Entry* find_pid(unsigned long pid)
queue = &scheduler.swait[p];
prev = &queue->start;
entry = prev->next;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
if (((struct Thread*)entry->value)->pid == pid)
return prev;
prev = entry;
@@ -163,20 +127,14 @@ struct Entry* find_pid(unsigned long pid)
return 0;
}
+/// Find the next thread waiting on this mutex
struct Entry* find_mutex_wait_next(void* m)
{
- for (unsigned char p = 0; p < PRIORITIES; p++) {
- struct Queue* queue = &scheduler.mwait[p];
- struct Entry* prev = &queue->start;
- struct Entry* entry = prev->next;
- while (entry->entry_type != END_ENTRY) {
- if (((struct Thread*)entry->value)->mptr == m)
- return prev;
- prev = entry;
- entry = entry->next;
- }
- }
- return 0;
+ unsigned long spacing = (unsigned long)&mutexs[1] - (unsigned long)&mutexs[0];
+ unsigned long difference = (unsigned long)m - (unsigned long)&mutexs[0];
+ unsigned long index = difference/spacing;
+ struct Entry* entry = mutexs[index].waiting_threads;
+ return entry;
}
struct Entry* find_signal_wait_next(void* s)
@@ -185,7 +143,7 @@ struct Entry* find_signal_wait_next(void* s)
struct Queue* queue = &scheduler.swait[p];
struct Entry* prev = &queue->start;
struct Entry* entry = prev->next;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
if (((struct Thread*)entry->value)->mptr == s)
return prev;
prev = entry;
@@ -200,7 +158,7 @@ struct Entry* get_unused_thread(void)
struct Queue* q = &scheduler.free_threads;
// If we have no available free threads
// return null pointer
- if (q->start.next->entry_type == END_ENTRY)
+ if (q->start.next == 0)
return 0;
// Otherwise, get the next thread
return pop_from_queue(q);
@@ -211,7 +169,7 @@ unsigned char find_duplicate(void* pc)
for (unsigned char p = 0; p < PRIORITIES; p++) {
struct Queue* queue = &scheduler.ready[p];
struct Entry* entry = queue->start.next;
- while (entry->entry_type == VALUE_ENTRY) {
+ while (entry != 0) {
if (((struct Thread*)entry->value)->pc == pc) {
return 1;
}
@@ -282,7 +240,7 @@ void uart_scheduler(void)
uart_string("Ready Queue\n");
entry = queue->start.next;
length = 0;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
uart_hex((unsigned long)entry->value);
uart_char(' ');
kmemshow32((void*)entry->value, 9);
@@ -295,7 +253,7 @@ void uart_scheduler(void)
uart_string("Mutex Wait Queue\n");
entry = queue->start.next;
length = 0;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
uart_hex((unsigned long)entry->value);
uart_char(' ');
kmemshow32((void*)entry->value, 9);
@@ -308,7 +266,7 @@ void uart_scheduler(void)
uart_string("Signal Wait Queue\n");
entry = queue->start.next;
length = 0;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
uart_hex((unsigned long)entry->value);
uart_char(' ');
kmemshow32((void*)entry->value, 9);
@@ -320,7 +278,7 @@ void uart_scheduler(void)
// Count number of free threads
struct Queue* queue = &scheduler.free_threads;
struct Entry* entry = queue->start.next;
- while (entry->entry_type != END_ENTRY) {
+ while (entry != 0) {
entry = entry->next;
length++;
}
@@ -333,7 +291,7 @@ struct Thread* next_thread(void)
// Recurse through all priorities to try to find a ready thread
for (int p = 0; p < PRIORITIES; p++) {
struct Queue* rq = &scheduler.ready[p];
- if (rq->start.next->entry_type == END_ENTRY)
+ if (rq->start.next == 0)
continue;
return rq->start.next->value;
}
@@ -384,7 +342,7 @@ void sched_mutex_yield(void* m)
push_thread_to_queue(rt->value, THREAD_MWAIT, priority);
// Find the thread that has the mutex locked
struct Mutex* mtex = m;
- struct Entry* mutex_next = find_pid(mtex->pid);
+ struct Entry* mutex_next = mtex->locking_thread;
if (mutex_next == 0)
return;
// The next thread is the one with the lock
@@ -445,7 +403,7 @@ unsigned long sched_mutex_resurrect(void* m)
struct Entry* tentry = pop_thread_from_queue(THREAD_READY, p);
((struct Thread*)tentry->value)->priority = op;
((struct Thread*)tentry->value)->old_priority = 0xFF;
- prepend_thread_to_queue(tentry->value, THREAD_READY, op);
+ push_thread_to_queue(tentry->value, THREAD_READY, op);
}
return 1;
}
generated by cgit v1.2.1 (git 2.18.0) at 2024-05-18 12:48:03 +0000