s390/topology: convert cpu_topology array to per cpu variable

Convert the per cpu topology cpu masks to a per cpu variable.
At least for machines which do have less possible cpus than NR_CPUS this can
save a bit of memory (z/VM: max 64 vs 512 for performance_defconfig).

This reduces the kernel image size by 100k.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/topology.h b/arch/s390/include/asm/topology.h
index 9454231..b1453a2 100644
--- a/arch/s390/include/asm/topology.h
+++ b/arch/s390/include/asm/topology.h
@@ -18,15 +18,15 @@
 	cpumask_t book_mask;
 };
 
-extern struct cpu_topology_s390 cpu_topology[NR_CPUS];
+DECLARE_PER_CPU(struct cpu_topology_s390, cpu_topology);
 
-#define topology_physical_package_id(cpu)	(cpu_topology[cpu].socket_id)
-#define topology_thread_id(cpu)			(cpu_topology[cpu].thread_id)
-#define topology_thread_cpumask(cpu)		(&cpu_topology[cpu].thread_mask)
-#define topology_core_id(cpu)			(cpu_topology[cpu].core_id)
-#define topology_core_cpumask(cpu)		(&cpu_topology[cpu].core_mask)
-#define topology_book_id(cpu)			(cpu_topology[cpu].book_id)
-#define topology_book_cpumask(cpu)		(&cpu_topology[cpu].book_mask)
+#define topology_physical_package_id(cpu) (per_cpu(cpu_topology, cpu).socket_id)
+#define topology_thread_id(cpu)		  (per_cpu(cpu_topology, cpu).thread_id)
+#define topology_thread_cpumask(cpu)	  (&per_cpu(cpu_topology, cpu).thread_mask)
+#define topology_core_id(cpu)		  (per_cpu(cpu_topology, cpu).core_id)
+#define topology_core_cpumask(cpu)	  (&per_cpu(cpu_topology, cpu).core_mask)
+#define topology_book_id(cpu)		  (per_cpu(cpu_topology, cpu).book_id)
+#define topology_book_cpumask(cpu)	  (&per_cpu(cpu_topology, cpu).book_mask)
 
 #define mc_capable() 1