Initial commit

src/scheduler/sched.c

@@ -0,0 +1,123 @@
+#include <stdio.h>
+#include <string.h>
+#include <SFB25.h>
+#include "../hal/smp.h"
+#include <error.h>
+#include "../mm/kmalloc.h"
+#include "sched.h"
+
+extern context *save_context();
+
+extern void switch_context(context *old, context *new);
+
+#define QUANTUM_US 10000
+
+int next_pid = 1;
+
+void idle_task(){
+    kprintf("Hello world from bruhd task!\n");
+    for(;;);
+}
+
+void test_task(){
+    kprintf("Hello world from scheduled task!\n");
+    return;
+}
+
+/* Setup a process structure */
+proc *alloc_process(void){
+    asm("cli");
+
+    cpu_state *state = get_cpu_struct();
+    kprintf("hi10\n");
+    proc *proc_list = state->process_list;
+
+    uint8_t *sp;
+
+    for(uint64_t i = 0; i < PROC_MAX; i++){
+        if(proc_list[i].state == UNUSED){
+            /* Set the process ready to be executed */
+            kprintf("hi6\n");
+            proc_list[i].state = READY;
+            proc_list[i].kstack = kmalloc(INITIAL_STACK_SIZE);
+
+            if(proc_list[i].kstack == NULL){
+                klog(LOG_ERROR, __func__, "Failed to alloc stack");
+            }
+            kprintf("hi7\n");
+
+            proc_list[i].pid = next_pid++;
+
+            sp = (uint8_t*)((uint64_t)proc_list[i].kstack + INITIAL_STACK_SIZE);
+
+            proc_list[i].context.rip = 0;
+            proc_list[i].context.rsp = (uint64_t)sp;
+
+            kprintf("hi8\n");
+
+            asm("sti");
+
+            return &proc_list[i];
+        }
+    }
+    asm("sti");
+
+    return NULL;
+}
+
+kstatus add_task(uint64_t *entry){
+    proc *proc = alloc_process();
+
+    if (proc == NULL) {
+        klog(LOG_ERROR, __func__, "proc == null!");
+        kkill();
+    }
+
+    proc->context.rip = (uint64_t)entry;
+
+    return KERNEL_STATUS_SUCCESS;
+}
+
+void scheduler_init(){
+    cpu_state *state = get_cpu_struct();
+
+    if(state->current_process != NULL){
+        kprintf("sched: scheduler on CPU {d} already initialized!\n", state->lapic_id);
+        kkill();
+    }
+    kprintf("hi1\n");
+    proc *proc_list = state->process_list;
+
+    /* Put the idle task */
+    proc idle = {0, 0, 0, READY, {0, 0, 0, 0, 0, 0, 0, 0, 0}};
+
+    /* Make the idle structure the firstr process */
+    proc_list[0] = idle;
+
+    kprintf("hi2\n");
+    add_task((uint64_t*)test_task);
+    kprintf("hi5\n");
+
+    for(;;){
+        for(int i = 0; i < PROC_MAX; i++){
+            if(proc_list[i].state == READY){
+                
+                context old_state = state->current_process->context;
+
+                state->current_process = &proc_list[i];
+                state->current_process->state = RUNNING;
+
+                switch_context(&old_state, &state->current_process->context);
+
+            }
+        }
+    }
+}
+
+void scheduler_tick(){
+    cpu_state *state = get_cpu_struct();
+    proc *proc_list = state->process_list;
+
+
+
+}