diff --git a/kobject-example.c b/kobject-example.c
index bb904cf..477ab9b 100644
--- a/kobject-example.c
+++ b/kobject-example.c
@@ -3,82 +3,72 @@
 #include <linux/sysfs.h>
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/percpu-refcount.h>
 
-static int foo;
-static int baz;
-static int bar;
+static struct kobject *example_kobj;
+static struct percpu_ref global_ref;
 
-static ssize_t foo_show(struct kobject *kobj, struct kobj_attribute *attr,
+static void global_ref_release(struct percpu_ref *)
+{
+	printk("%s %d\n", __func__, __LINE__);
+}
+
+static ssize_t is_percpu_show(struct kobject *kobj, struct kobj_attribute *attr,
 			char *buf)
 {
-	return sysfs_emit(buf, "%d\n", foo);
+	unsigned long __percpu *percpu_count;
+	return sysfs_emit(buf, "%d\n", __ref_is_percpu(&global_ref, &percpu_count));
 }
+static struct kobj_attribute is_percpu_attribute = __ATTR_RO(is_percpu);
 
-static ssize_t foo_store(struct kobject *kobj, struct kobj_attribute *attr,
-			 const char *buf, size_t count)
+static ssize_t is_dying_show(struct kobject *kobj, struct kobj_attribute *attr,
+			char *buf)
 {
-	int ret;
-
-	ret = kstrtoint(buf, 10, &foo);
-	if (ret < 0)
-		return ret;
-
-	return count;
+	return sysfs_emit(buf, "%d\n", percpu_ref_is_dying(&global_ref));
 }
+static struct kobj_attribute is_dying_attribute = __ATTR_RO(is_dying);
 
-static struct kobj_attribute foo_attribute =
-	__ATTR(foo, 0664, foo_show, foo_store);
-
-static ssize_t b_show(struct kobject *kobj, struct kobj_attribute *attr,
-		      char *buf)
+static ssize_t is_zero_show(struct kobject *kobj, struct kobj_attribute *attr,
+			char *buf)
 {
-	int var;
-
-	if (strcmp(attr->attr.name, "baz") == 0)
-		var = baz;
-	else
-		var = bar;
-	return sysfs_emit(buf, "%d\n", var);
+	return sysfs_emit(buf, "%d\n", percpu_ref_is_zero(&global_ref));
 }
+static struct kobj_attribute is_zero_attribute = __ATTR_RO(is_zero);
 
-static ssize_t b_store(struct kobject *kobj, struct kobj_attribute *attr,
-		       const char *buf, size_t count)
+static ssize_t kill_store(struct kobject *kobj, struct kobj_attribute *attr,
+                         const char *buf, size_t count)
 {
-	int var, ret;
-
-	ret = kstrtoint(buf, 10, &var);
-	if (ret < 0)
-		return ret;
-
-	if (strcmp(attr->attr.name, "baz") == 0)
-		baz = var;
-	else
-		bar = var;
-	return count;
+	percpu_ref_kill(&global_ref);
+        return count;
 }
+static struct kobj_attribute kill_attribute = __ATTR_WO(kill);
 
-static struct kobj_attribute baz_attribute =
-	__ATTR(baz, 0664, b_show, b_store);
-static struct kobj_attribute bar_attribute =
-	__ATTR(bar, 0664, b_show, b_store);
+static ssize_t resurrect_store(struct kobject *kobj, struct kobj_attribute *attr,
+                         const char *buf, size_t count)
+{
+	percpu_ref_resurrect(&global_ref);
+        return count;
+}
+static struct kobj_attribute resurrect_attribute = __ATTR_WO(resurrect);
 
 static struct attribute *attrs[] = {
-	&foo_attribute.attr,
-	&baz_attribute.attr,
-	&bar_attribute.attr,
-	NULL,	/* need to NULL terminate the list of attributes */
+	&is_dying_attribute.attr,
+	&is_zero_attribute.attr,
+	&is_percpu_attribute.attr,
+	&kill_attribute.attr,
+	&resurrect_attribute.attr,
+	NULL,
 };
-
 static struct attribute_group attr_group = {
 	.attrs = attrs,
 };
 
-static struct kobject *example_kobj;
-
 static int __init example_init(void)
 {
 	int retval;
 
+	retval = percpu_ref_init(&global_ref, global_ref_release, PERCPU_REF_INIT_ATOMIC, GFP_KERNEL);
+
 	example_kobj = kobject_create_and_add("kobject_example", kernel_kobj);
 	if (!example_kobj)
 		return -ENOMEM;