diff --git a/include/asm-s390/topology.h b/include/asm-s390/topology.h
index 8e97b06..d96c916 100644
--- a/include/asm-s390/topology.h
+++ b/include/asm-s390/topology.h
@@ -7,6 +7,10 @@
 
 cpumask_t cpu_coregroup_map(unsigned int cpu);
 
+extern cpumask_t cpu_core_map[NR_CPUS];
+
+#define topology_core_siblings(cpu)	(cpu_core_map[cpu])
+
 int topology_set_cpu_management(int fc);
 void topology_schedule_update(void);