GDT finally works

kernel/spinlock.h

@@ -0,0 +1,31 @@
+#ifndef SPINLOCK_SPINLOCK_H_
+#define SPINLOCK_SPINLOCK_H_
+
+#include <stdatomic.h>
+#include "hal/hal.h"
+
+typedef atomic_bool SpinLock;
+
+// Spin more efficiently - cpu dependant
+#if defined(__x86_64__)
+# define SPINLOCK_HINT() asm volatile("pause")
+#else
+# define SPINLOCK_HINT()
+#endif
+
+#define SPINLOCK_ACQUIRE(sl) \
+  do { \
+    bool __unlocked = false; \
+    while (!atomic_compare_exchange_weak((sl), &__unlocked, true)) { \
+      SPINLOCK_HINT(); \
+    } \
+  } while(0)
+
+#define SPINLOCK_RELEASE(sl) \
+  do { \
+    atomic_store((sl), false); \
+  } while(0)
+
+#define SPINLOCK_INIT() false
+
+#endif // SPINLOCK_SPINLOCK_H_