cpu/hotplug: Use DEVICE_ATTR_*() macro

Use DEVICE_ATTR_*() helper instead of plain DEVICE_ATTR,
which makes the code a bit shorter and easier to read.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210527141105.2312-1-yuehaibing@huawei.com

kernel/cpu.c

@@ -2249,18 +2249,17 @@ int cpuhp_smt_enable(void)
 #endif
 
 #if defined(CONFIG_SYSFS) && defined(CONFIG_HOTPLUG_CPU)
-static ssize_t show_cpuhp_state(struct device *dev,
-				struct device_attribute *attr, char *buf)
+static ssize_t state_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
 {
 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id);
 
 	return sprintf(buf, "%d\n", st->state);
 }
-static DEVICE_ATTR(state, 0444, show_cpuhp_state, NULL);
+static DEVICE_ATTR_RO(state);
 
-static ssize_t write_cpuhp_target(struct device *dev,
-				  struct device_attribute *attr,
-				  const char *buf, size_t count)
+static ssize_t target_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count)
 {
 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id);
 	struct cpuhp_step *sp;
@@ -2298,19 +2297,17 @@ static ssize_t write_cpuhp_target(struct device *dev,
 	return ret ? ret : count;
 }
 
-static ssize_t show_cpuhp_target(struct device *dev,
-				 struct device_attribute *attr, char *buf)
+static ssize_t target_show(struct device *dev,
+			   struct device_attribute *attr, char *buf)
 {
 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id);
 
 	return sprintf(buf, "%d\n", st->target);
 }
-static DEVICE_ATTR(target, 0644, show_cpuhp_target, write_cpuhp_target);
-
+static DEVICE_ATTR_RW(target);
 
-static ssize_t write_cpuhp_fail(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count)
+static ssize_t fail_store(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
 {
 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id);
 	struct cpuhp_step *sp;
@@ -2359,15 +2356,15 @@ static ssize_t write_cpuhp_fail(struct device *dev,
 	return count;
 }
 
-static ssize_t show_cpuhp_fail(struct device *dev,
-			       struct device_attribute *attr, char *buf)
+static ssize_t fail_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
 {
 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, dev->id);
 
 	return sprintf(buf, "%d\n", st->fail);
 }
 
-static DEVICE_ATTR(fail, 0644, show_cpuhp_fail, write_cpuhp_fail);
+static DEVICE_ATTR_RW(fail);
 
 static struct attribute *cpuhp_cpu_attrs[] = {
 	&dev_attr_state.attr,
@@ -2382,7 +2379,7 @@ static const struct attribute_group cpuhp_cpu_attr_group = {
 	NULL
 };
 
-static ssize_t show_cpuhp_states(struct device *dev,
+static ssize_t states_show(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
 	ssize_t cur, res = 0;
@@ -2401,7 +2398,7 @@ static ssize_t show_cpuhp_states(struct device *dev,
 	mutex_unlock(&cpuhp_state_mutex);
 	return res;
 }
-static DEVICE_ATTR(states, 0444, show_cpuhp_states, NULL);
+static DEVICE_ATTR_RO(states);
 
 static struct attribute *cpuhp_cpu_root_attrs[] = {
 	&dev_attr_states.attr,
@@ -2474,28 +2471,27 @@ static const char *smt_states[] = {
 	[CPU_SMT_NOT_IMPLEMENTED]	= "notimplemented",
 };
 
-static ssize_t
-show_smt_control(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t control_show(struct device *dev,
+			    struct device_attribute *attr, char *buf)
 {
 	const char *state = smt_states[cpu_smt_control];
 
 	return snprintf(buf, PAGE_SIZE - 2, "%s\n", state);
 }
 
-static ssize_t
-store_smt_control(struct device *dev, struct device_attribute *attr,
-		  const char *buf, size_t count)
+static ssize_t control_store(struct device *dev, struct device_attribute *attr,
+			     const char *buf, size_t count)
 {
 	return __store_smt_control(dev, attr, buf, count);
 }
-static DEVICE_ATTR(control, 0644, show_smt_control, store_smt_control);
+static DEVICE_ATTR_RW(control);
 
-static ssize_t
-show_smt_active(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t active_show(struct device *dev,
+			   struct device_attribute *attr, char *buf)
 {
 	return snprintf(buf, PAGE_SIZE - 2, "%d\n", sched_smt_active());
 }
-static DEVICE_ATTR(active, 0444, show_smt_active, NULL);
+static DEVICE_ATTR_RO(active);
 
 static struct attribute *cpuhp_smt_attrs[] = {
 	&dev_attr_control.attr,