+#if TW_TIMER_WHEELS > 1
+ fast_ring_index = tw->current_index[TW_TIMER_RING_FAST];
+ if (fast_ring_index == TW_SLOTS_PER_RING)
+ return 1;
+
+ first_expiring_index = clib_bitmap_next_set (tw->fast_slot_bitmap,
+ fast_ring_index);
+ if (first_expiring_index == ~0)
+ first_expiring_index = TW_SLOTS_PER_RING;
+
+#else
+