sched: add current_task(), current_thread(), and preempt_disable/enable()

sched/core.c

@@ -26,9 +26,11 @@ kern_status_t sched_init(void)
 		return status;
 	}
 
+	thread_t *this_thread = QUEUE_CONTAINER(thread_t, tr_threads, queue_first(&kernel_task()->t_threads));
+
 	cpu_data_t *this_cpu = get_this_cpu();
 	runqueue_init(&this_cpu->c_rq);
-	this_cpu->c_current_task = kernel_task();
+	this_cpu->c_current_thread = this_thread;
 	put_cpu(this_cpu);
 
 	printk("sched: initialised");

sched/task.c

@@ -77,3 +77,8 @@ task_t *task_from_pid(unsigned int pid)
 	spin_unlock_irqrestore(&task_list_lock, flags);
 	return t;
 }
+
+task_t *current_task(void)
+{
+	return current_thread()->tr_parent;
+}

sched/thread.c

@@ -1,5 +1,6 @@
 #include <socks/sched.h>
 #include <socks/object.h>
+#include <socks/cpu.h>
 
 static object_type_t thread_type = {
 	.ob_name = "thread",
@@ -17,7 +18,7 @@ thread_t *thread_alloc(void)
 	if (!thread_obj) {
 		return NULL;
 	}
-	
+
 	thread_t *t = object_data(thread_obj);
 	memset(t, 0x00, sizeof *t);
 	return t;
@@ -27,3 +28,16 @@ void thread_free(thread_t *thr)
 {
 
 }
+
+thread_t *current_thread(void)
+{
+	cpu_data_t *cpu = get_this_cpu();
+	thread_t *out = cpu->c_current_thread;
+	put_cpu(cpu);
+	return out;
+}
+
+bool need_resched(void)
+{
+	return (current_thread()->tr_flags & THREAD_F_NEED_RESCHED) != 0;
+}