-#define THREAD_SIZE (8192)
-
-extern struct thread_info *alloc_thread_info(struct task_struct *task);
-extern void free_thread_info(struct thread_info *);
+/* thread information allocation */
+#ifdef CONFIG_DEBUG_STACK_USAGE
+#define alloc_thread_info(tsk) \
+ ((struct thread_info *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, \
+ THREAD_SIZE_ORDER))
+#else
+#define alloc_thread_info(tsk) \
+ ((struct thread_info *)__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER))
+#endif