cpu: change cpu_sys_devices from array to per_cpu variable

Change cpu_sys_devices from array to per_cpu variable in drivers/base/cpu.c.
Signed-off-by: NMike Travis <travis@sgi.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/base/cpu.c

@@ -18,7 +18,7 @@ struct sysdev_class cpu_sysdev_class = {
 };
 EXPORT_SYMBOL(cpu_sysdev_class);
 
-static struct sys_device *cpu_sys_devices[NR_CPUS];
+static DEFINE_PER_CPU(struct sys_device *, cpu_sys_devices);
 
 #ifdef CONFIG_HOTPLUG_CPU
 static ssize_t show_online(struct sys_device *dev, char *buf)
@@ -68,7 +68,7 @@ void unregister_cpu(struct cpu *cpu)
 	sysdev_remove_file(&cpu->sysdev, &attr_online);
 
 	sysdev_unregister(&cpu->sysdev);
-	cpu_sys_devices[logical_cpu] = NULL;
+	per_cpu(cpu_sys_devices, logical_cpu) = NULL;
 	return;
 }
 #else /* ... !CONFIG_HOTPLUG_CPU */
@@ -167,7 +167,7 @@ int __cpuinit register_cpu(struct cpu *cpu, int num)
 	if (!error && cpu->hotpluggable)
 		register_cpu_control(cpu);
 	if (!error)
-		cpu_sys_devices[num] = &cpu->sysdev;
+		per_cpu(cpu_sys_devices, num) = &cpu->sysdev;
 	if (!error)
 		register_cpu_under_node(num, cpu_to_node(num));
 
@@ -180,8 +180,8 @@ int __cpuinit register_cpu(struct cpu *cpu, int num)
 
 struct sys_device *get_cpu_sysdev(unsigned cpu)
 {
-	if (cpu < NR_CPUS)
-		return cpu_sys_devices[cpu];
+	if (cpu < nr_cpu_ids && cpu_possible(cpu))
+		return per_cpu(cpu_sys_devices, cpu);
 	else
 		return NULL;
 }