diff -urNp linux-2.5.45-ia64/include/asm-ia64/system.h linux-2.5.45-ia64-o1fix/include/asm-ia64/system.h
--- linux-2.5.45-ia64/include/asm-ia64/system.h	Mon Nov  4 19:31:52 2002
+++ linux-2.5.45-ia64-o1fix/include/asm-ia64/system.h	Mon Nov  4 19:46:35 2002
@@ -432,6 +432,18 @@ extern void ia64_load_extra (struct task
 } while (0)
 #endif
 
+#define prepare_arch_switch(rq, next)		\
+do {	spin_lock(&(next)->switch_lock);	\
+	spin_unlock(&(rq)->lock);		\
+} while (0)
+
+#define finish_arch_switch(rq, prev)		\
+do {	spin_unlock_irq(&(prev)->switch_lock);	\
+} while (0)
+
+#define task_running(rq, p) \
+	((rq)->curr == (p) || spin_is_locked(&(p)->switch_lock))
+
 #endif /* __KERNEL__ */
 
 #endif /* __ASSEMBLY__ */