Make proc->state not atomic

kernel/amd64/proc.c

@@ -29,7 +29,7 @@ struct proc* proc_from_elf (uint8_t* elf_contents) {
   memset (proc, 0, sizeof (*proc));
 
   proc->lock = SPIN_LOCK_INIT;
-  atomic_store (&proc->state, PROC_READY);
+  proc->state = PROC_READY;
   proc->pid = atomic_fetch_add (&pids, 1);
 
   proc->procgroup = procgroup_create ();
@@ -71,7 +71,7 @@ struct proc* proc_clone (struct proc* proto, uintptr_t vstack_top, uintptr_t ent
   memset (proc, 0, sizeof (*proc));
 
   proc->lock = SPIN_LOCK_INIT;
-  atomic_store (&proc->state, PROC_READY);
+  proc->state = PROC_READY;
   proc->pid = atomic_fetch_add (&pids, 1);
 
   spin_lock (&proto->lock);

kernel/proc/proc.c

@@ -233,7 +233,11 @@ static struct proc* proc_find_sched (struct cpu* cpu) {
   do {
     struct proc* proc = list_entry (current, struct proc, cpu_run_q_link);
 
-    if (atomic_load (&proc->state) == PROC_READY)
+    spin_lock (&proc->lock);
+    int state = proc->state;
+    spin_unlock (&proc->lock);
+
+    if (state == PROC_READY)
       return proc;
 
     current = current->next ? current->next : cpu->proc_run_q;
@@ -256,13 +260,16 @@ static void proc_reap (struct reschedule_ctx* rctx) {
     rbtree_next (node, next);
     proc = rbtree_entry (node, struct proc, proc_tree_link);
 
-    if (atomic_load (&proc->state) == PROC_DEAD) {
+    node = next;
+
     spin_lock (&proc->lock);
+
+    if (proc->state == PROC_DEAD) {
       list_append (reap_list, &proc->reap_link);
-      spin_unlock (&proc->lock);
+      rbtree_delete (&proc_tree, &proc->proc_tree_link);
     }
 
-    node = next;
+    spin_unlock (&proc->lock);
   }
 
   spin_unlock (&proc_tree_lock);
@@ -270,8 +277,9 @@ static void proc_reap (struct reschedule_ctx* rctx) {
   struct list_node_link *reap_link, *reap_link_tmp;
   list_foreach (reap_list, reap_link, reap_link_tmp) {
     proc = list_entry (reap_link, struct proc, reap_link);
-    rbtree_delete (&proc_tree, &proc->proc_tree_link);
+
     list_remove (reap_list, &proc->reap_link);
+
     DEBUG ("cleanup PID %d\n", proc->pid);
     proc_cleanup (proc, rctx);
   }
@@ -311,7 +319,7 @@ void proc_kill (struct proc* proc, struct reschedule_ctx* rctx) {
   spin_lock (&cpu->lock);
   spin_lock (&proc->lock);
 
-  atomic_store (&proc->state, PROC_DEAD);
+  proc->state = PROC_DEAD;
   proc->cpu = NULL;
 
   list_remove (cpu->proc_run_q, &proc->cpu_run_q_link);

kernel/proc/proc.h

@@ -41,7 +41,7 @@ struct proc {
   uint32_t flags;
   spin_lock_t lock;
   struct cpu* cpu;
-  atomic_int state;
+  int state;
   uintptr_t uvaddr_argument;
   void* mail_recv_buffer;
   size_t mail_recv_size;

kernel/proc/suspension_q.c

@@ -28,7 +28,7 @@ void proc_sq_suspend (struct proc* proc, struct proc_suspension_q* sq, spin_lock
 
   spin_unlock (resource_lock);
 
-  atomic_store (&proc->state, PROC_SUSPENDED);
+  proc->state = PROC_SUSPENDED;
 
   /* append to sq's list */
   list_append (sq->proc_list, &sq_entry->sq_link);
@@ -70,7 +70,7 @@ void proc_sq_resume (struct proc* proc, struct proc_sq_entry* sq_entry,
   proc->cpu = cpu;
 
   if (proc->sq_entries == NULL)
-    atomic_store (&proc->state, PROC_READY);
+    proc->state = PROC_READY;
 
   list_append (cpu->proc_run_q, &proc->cpu_run_q_link);
   cpu->proc_run_q_count++;