Work on scheduler

include/smp.h

@@ -20,7 +20,8 @@ typedef struct cpu_state {
 }cpu_state;
 
 void smp_init();
-cpu_state *get_cpu_struct();
+cpu_state *get_current_cpu_state();
+cpu_state *get_cpu_state(int);
 uint64_t get_cpu_count();
 void bsp_early_init();
 bool get_cpu_struct_initialized();

src/arch/amd64/hal/apic.c

@@ -47,10 +47,10 @@ uint32_t lapic_read_reg(uint32_t reg){
 }
 
 void apic_sleep(uint64_t ms){
-    uint64_t lapic_timer_ticks = get_cpu_struct()->lapic_timer_ticks;
-    uint64_t curcnt = get_cpu_struct()->lapic_timer_ticks;
+    uint64_t lapic_timer_ticks = get_current_cpu_struct()->lapic_timer_ticks;
+    uint64_t curcnt = get_current_cpu_struct()->lapic_timer_ticks;
     while (lapic_timer_ticks - curcnt < ms) {
-        lapic_timer_ticks = get_cpu_struct()->lapic_timer_ticks;
+        lapic_timer_ticks = get_current_cpu_struct()->lapic_timer_ticks;
     }
 }
 
@@ -129,7 +129,7 @@ void ap_apic_init(){
 void apic_timer_handler(){
 
     if(get_cpu_struct_initialized()){
-        get_cpu_struct()->lapic_timer_ticks++;
+        get_current_cpu_struct()->lapic_timer_ticks++;
     }
 
     lapic_write_reg(LAPIC_EOI_REG, 0);

src/arch/amd64/hal/idt.c

@@ -241,7 +241,7 @@ void interrupt_handler(interrupt_frame *r){
     }
 
     if(r->int_no == 69 && get_cpu_struct_initialized()
-     && get_cpu_struct()->scheduler_initialized){
+     && get_current_cpu_struct()->scheduler_initialized){
         yield();
         return;
     }

src/kinfo.c

@@ -37,6 +37,7 @@ void initialize_kinfo(){
     kinfo.cmdline = executable_cmdline_request.response->cmdline;
     kinfo.cpu_count = smp_request.response->cpu_count;
     kinfo.boot_timestamp = date_at_boot_request.response->timestamp;
+
     #ifdef __x86_64__
         kinfo.bsp_id = smp_request.response->bsp_lapic_id;
     #endif

src/lib/lock.c

@@ -29,7 +29,7 @@ struct mutex *init_mutex(){
 
 kstatus try_mutex(struct mutex *mut){
     if(!atomic_flag_test_and_set_explicit(&mut->lock, memory_order_acquire)){
-        mut->holder = get_cpu_struct()->current_process;
+        mut->holder = get_current_cpu_struct()->current_process;
         mut->locked = true;
         return KERNEL_MUTEX_ACQUIRED;
     }
@@ -40,7 +40,7 @@ kstatus try_mutex(struct mutex *mut){
 
 kstatus acquire_mutex(struct mutex *mut){
 
-    if(get_cpu_struct()->current_process == mut->holder){
+    if(get_current_cpu_struct()->current_process == mut->holder){
         klog(__func__, "Holder attempted to acquire mutex");
         return KERNEL_STATUS_ERROR;
     }

src/scheduler/sched.c

@@ -1,6 +1,7 @@
 
 #include <assert.h>
 #include <kprint.h>
+#include <stdatomic.h>
 #include <stdint.h>
 #include <neobbo.h>
 #include <smp.h>
@@ -9,6 +10,7 @@
 #include <mm/kmalloc.h>
 #include <mm/slab.h>
 #include <scheduler/sched.h>
+#include <lock.h>
 
 extern void switch_context(struct context **old, struct context *new);
 extern void sched_enter(void *a);
@@ -42,7 +44,7 @@ void thread_exit(){
         asm("cli");
     #endif
 
-    cpu_state *cpu = get_cpu_struct();
+    cpu_state *cpu = get_current_cpu_state();
     struct thread *p = cpu->current_process;
 
     if(p == p->next && p->prev == p){
@@ -70,11 +72,8 @@ struct thread *alloc_thread(void){
 
     t->kstack = kzalloc(8 * 4096);
 
-    t->pid = next_pid++;
-
     uint64_t *sp = (uint64_t*)((uint64_t)t->kstack + 8 * 4096);
 
-
     // Push the exit function (the thread will return to it when it finishes)
     *--sp = (uint64_t)thread_exit;
     
@@ -93,9 +92,9 @@ struct thread *add_thread(uint64_t *entry){
 
     assert(t != NULL && "Thread allocation failed!");
 
-    struct cpu_state *cpu = get_cpu_struct();
-    struct thread *head = get_cpu_struct()->head;
-    struct thread *base = get_cpu_struct()->base;    
+    struct cpu_state *cpu = get_current_cpu_state();
+    struct thread *head = get_current_cpu_state()->head;
+    struct thread *base = get_current_cpu_state()->base;    
 
     // Manage circley linked list
     if(base == NULL){
@@ -113,12 +112,25 @@ struct thread *add_thread(uint64_t *entry){
 
     t->context->rip = (uint64_t)entry;
 
+    t->pid = next_pid++;
+
     return t;
 }
 
+// This function determines to which CPU a new thread should be added
+kstatus spawn_thread(struct thread *thread){
+    uint64_t cpu_count = get_kinfo()->cpu_count;
+    uint16_t i = 0;
+    for(i = 0; i < cpu_count; i++){
+        if(get_cpu_state(i)->scheduler_initialized){
+    }
+
+
+}
+
 
 [[noreturn]] void sched(){
-    cpu_state *cpu = get_cpu_struct();
+    cpu_state *cpu = get_current_cpu_struct();
     cpu->scheduler_initialized = true; // Allow us to get interrupts that schedule us
     for(;;){
         #ifdef __x86_64__
@@ -127,8 +139,12 @@ struct thread *add_thread(uint64_t *entry){
         
         struct thread *prev = cpu->current_process;
 
+        if(prev == NULL && cpu->head == NULL){
+            continue;
+        }
+
         if(cpu->head == NULL){
-            cpu->current_process = idle;
+            continue;
         }else{
             cpu->current_process = cpu->head;
             cpu->head = cpu->head->next;
@@ -141,14 +157,16 @@ struct thread *add_thread(uint64_t *entry){
         }
 
         cpu->current_process->state = RUNNING;
-        switch_context(&(get_cpu_struct()->scheduler_context), get_cpu_struct()->current_process->context);
+        switch_context(&(get_current_cpu_struct()->scheduler_context), get_current_cpu_struct()->current_process->context);
     }
 }
 
+static atomic_flag scheduler_init_lock = ATOMIC_FLAG_INIT;
 void scheduler_init(){
+    acquire_spinlock(&scheduler_init_lock);
     assert(get_cpu_struct_initialized() && "CPU struct not initialized!");
 
-    cpu_state *cpu = get_cpu_struct();
+    cpu_state *cpu = get_current_cpu_struct();
 
     if(cpu->current_process != NULL){
         kprintf("scheduler on CPU {d} already initialized!\n", cpu->id);
@@ -161,9 +179,11 @@ void scheduler_init(){
         assert(idle != NULL && "Failed to allocate idle task!");
     }
 
-    cpu->current_process = idle;
+    //cpu->current_process = idle;
 
-    kprintf("scheduler on CPU {d} initialized!", cpu->id);
+    kprintf("scheduler on CPU {d} initialized!\n", cpu->id);
+
+    free_spinlock(&scheduler_init_lock);
 
     sched();
     
@@ -175,5 +195,5 @@ void yield(){
     #ifdef __x86_64__
         asm("cli");
     #endif
-    switch_context(&get_cpu_struct()->current_process->context, get_cpu_struct()->scheduler_context);
+    switch_context(&get_current_cpu_struct()->current_process->context, get_current_cpu_struct()->scheduler_context);
 }

src/smp.c

@@ -19,17 +19,17 @@ extern void s_load_idt();
 extern void s_load_gdt();
 extern volatile struct limine_mp_request smp_request;
 
+static cpu_state *cpus;
+
+static cpu_state bsp_cpu;
+
 /* Returns the CPU structure for this particular CPU */
-cpu_state *get_cpu_struct(){
+cpu_state *get_current_cpu_struct(){
     return (cpu_state*)rdmsr(GSBASE);
 }
 
-uint64_t get_cpu_count(){
-    if(smp_request.response != NULL){
-        return smp_request.response->cpu_count;
-    }
-
-    return 0;
+cpu_state *get_cpu_struct(int id){
+    return &cpus[id];
 }
 
 bool get_cpu_struct_initialized(){
@@ -63,37 +63,41 @@ void ap_init(struct limine_mp_info *smp_info){
         : : : "rax"
     );
 
-    cpu_state *cpu_struct = (cpu_state*)kzalloc(sizeof(cpu_state));
+    cpu_state cpu_struct = cpus[smp_info->lapic_id];
 
-    cpu_struct->id = smp_info->lapic_id;
+    cpu_struct.id = smp_info->lapic_id;
 
-    wrmsr(KERNELGSBASE, (uint64_t)cpu_struct);
-    wrmsr(GSBASE, (uint64_t)cpu_struct);
+    wrmsr(KERNELGSBASE, (uint64_t)&cpu_struct);
+    wrmsr(GSBASE, (uint64_t)&cpu_struct);
 
     /* Initialize APIC & APIC timer */
     ap_apic_init();
 
     free_spinlock(&ap_init_lock);
 
-    for(;;);
+    while(!bsp_cpu.scheduler_initialized){
+        __builtin_ia32_pause();
+    }
 
     scheduler_init();
 }
 
-static cpu_state bsp_cpu;
-
 void smp_init(){
 
     struct limine_mp_response *smp_response = smp_request.response;
 
     kprintf("smp: {d} CPUs\n", smp_response->cpu_count);
 
-    for(uint64_t i = 0; i < smp_response->cpu_count; i++){
+    cpus = (cpu_state *)kzalloc(sizeof(cpu_state) * smp_response->cpu_count);
+
+    for(uint64_t i = 1; i < smp_response->cpu_count; i++){
         /* Pointer to smp_info is passed in RDI by Limine, so no need to pass any arguments here */
         smp_response->cpus[i]->goto_address = &ap_init;
     }
 
-    bsp_cpu.scheduler_context = (struct context*)kmalloc(sizeof(struct context));
+    bsp_cpu.scheduler_context = (struct context*)kzalloc(sizeof(struct context));
+
+    cpus[bsp_cpu.id] = bsp_cpu;
 
     /* If one of the APs has halted, then halt the BSP */
     extern bool kernel_killed;

src/sys/time.c

@@ -17,7 +17,7 @@ uint64_t get_timestamp_us(){
         }
 
         if(get_cpu_struct_initialized()){
-            return get_cpu_struct()->lapic_timer_ticks * 1000ULL;
+            return get_current_cpu_struct()->lapic_timer_ticks * 1000ULL;
         }
 
     #endif

uacpi_kernel_api.c

@@ -206,7 +206,7 @@ void uacpi_kernel_free_event(uacpi_handle handle){
 }
 
 uacpi_thread_id uacpi_kernel_get_thread_id(void){
-    return get_cpu_struct();
+    return get_current_cpu_struct();
 }
 
 uacpi_status uacpi_kernel_acquire_mutex(uacpi_handle handle, uacpi_u16 t){