diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 0eff7e9..b17c984 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -11,6 +11,20 @@
 
 extern int noirqdebug;
 
+/*
+ * Bits used by threaded handlers:
+ * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
+ * IRQTF_DIED      - handler thread died
+ * IRQTF_WARNED    - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
+ * IRQTF_AFFINITY  - irq thread is requested to adjust affinity
+ */
+enum {
+	IRQTF_RUNTHREAD,
+	IRQTF_DIED,
+	IRQTF_WARNED,
+	IRQTF_AFFINITY,
+};
+
 #define irq_data_to_desc(data)	container_of(data, struct irq_desc, irq_data)
 
 /* Set default functions for irq_chip structures: */