Commit 8dba0fd9 authored by Vivek Yadav's avatar Vivek Yadav Committed by Rafael J. Wysocki
Browse files

cpuidle: sysfs: Use sysfs_emit()/sysfs_emit_at() instead of sprintf()/scnprintf() 



The ->show() callbacks in sysfs should use sysfs_emit() or
sysfs_emit_at() when formatting values for user space.

These helpers are the recommended way to ensure correct buffer
handling and consistency across the kernel.

See Documentation/filesystems/sysfs.rst for details.

No functional change intended.

Suggested-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarVivek Yadav <vivekyadav1207731111@gmail.com>
Link: https://patch.msgid.link/20250919165657.233349-1-vivekyadav1207731111@gmail.com


[ rjw: Minor subject edits ]
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent a2d100c4

drivers/cpuidle/sysfs.c

+17 −17
Original line number Diff line number Diff line
@@ -30,11 +30,11 @@ static ssize_t show_available_governors(struct device *dev, 
		if (i >= (ssize_t)(PAGE_SIZE - (CPUIDLE_NAME_LEN + 2)))

			goto out;



		i += scnprintf(&buf[i], CPUIDLE_NAME_LEN + 1, "%s ", tmp->name);

		i += sysfs_emit_at(buf, i, "%.*s ", CPUIDLE_NAME_LEN, tmp->name);

	}



out:

	i+= sprintf(&buf[i], "\n");

	i += sysfs_emit_at(buf, i, "\n");

	mutex_unlock(&cpuidle_lock);

	return i;

}
@@ -49,9 +49,9 @@ static ssize_t show_current_driver(struct device *dev, 
	spin_lock(&cpuidle_driver_lock);

	drv = cpuidle_get_driver();

	if (drv)

		ret = sprintf(buf, "%s\n", drv->name);

		ret = sysfs_emit(buf, "%s\n", drv->name);

	else

		ret = sprintf(buf, "none\n");

		ret = sysfs_emit(buf, "none\n");

	spin_unlock(&cpuidle_driver_lock);



	return ret;
@@ -65,9 +65,9 @@ static ssize_t show_current_governor(struct device *dev, 


	mutex_lock(&cpuidle_lock);

	if (cpuidle_curr_governor)

		ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);

		ret = sysfs_emit(buf, "%s\n", cpuidle_curr_governor->name);

	else

		ret = sprintf(buf, "none\n");

		ret = sysfs_emit(buf, "none\n");

	mutex_unlock(&cpuidle_lock);



	return ret;
@@ -230,7 +230,7 @@ static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0644, show, store) 
static ssize_t show_state_##_name(struct cpuidle_state *state, \

			 struct cpuidle_state_usage *state_usage, char *buf) \

{ \

	return sprintf(buf, "%u\n", state->_name);\

	return sysfs_emit(buf, "%u\n", state->_name);\

}



#define define_show_state_ull_function(_name) \
@@ -238,7 +238,7 @@ static ssize_t show_state_##_name(struct cpuidle_state *state, \ 
				  struct cpuidle_state_usage *state_usage, \

				  char *buf)				\

{ \

	return sprintf(buf, "%llu\n", state_usage->_name);\

	return sysfs_emit(buf, "%llu\n", state_usage->_name);\

}



#define define_show_state_str_function(_name) \
@@ -247,8 +247,8 @@ static ssize_t show_state_##_name(struct cpuidle_state *state, \ 
				  char *buf)				\

{ \

	if (state->_name[0] == '\0')\

		return sprintf(buf, "<null>\n");\

	return sprintf(buf, "%s\n", state->_name);\

		return sysfs_emit(buf, "<null>\n");\

	return sysfs_emit(buf, "%s\n", state->_name);\

}



#define define_show_state_time_function(_name) \
@@ -256,7 +256,7 @@ static ssize_t show_state_##_name(struct cpuidle_state *state, \ 
				  struct cpuidle_state_usage *state_usage, \

				  char *buf) \

{ \

	return sprintf(buf, "%llu\n", ktime_to_us(state->_name##_ns)); \

	return sysfs_emit(buf, "%llu\n", ktime_to_us(state->_name##_ns)); \

}



define_show_state_time_function(exit_latency)
@@ -273,14 +273,14 @@ static ssize_t show_state_time(struct cpuidle_state *state, 
			       struct cpuidle_state_usage *state_usage,

			       char *buf)

{

	return sprintf(buf, "%llu\n", ktime_to_us(state_usage->time_ns));

	return sysfs_emit(buf, "%llu\n", ktime_to_us(state_usage->time_ns));

}



static ssize_t show_state_disable(struct cpuidle_state *state,

				  struct cpuidle_state_usage *state_usage,

				  char *buf)

{

	return sprintf(buf, "%llu\n",

	return sysfs_emit(buf, "%llu\n",

		       state_usage->disable & CPUIDLE_STATE_DISABLED_BY_USER);

}
@@ -310,7 +310,7 @@ static ssize_t show_state_default_status(struct cpuidle_state *state, 
					  struct cpuidle_state_usage *state_usage,

					  char *buf)

{

	return sprintf(buf, "%s\n",

	return sysfs_emit(buf, "%s\n",

		       state->flags & CPUIDLE_FLAG_OFF ? "disabled" : "enabled");

}
@@ -358,7 +358,7 @@ static ssize_t show_state_s2idle_##_name(struct cpuidle_state *state, \ 
					 struct cpuidle_state_usage *state_usage, \

					 char *buf)				\

{ \

	return sprintf(buf, "%llu\n", state_usage->s2idle_##_name);\

	return sysfs_emit(buf, "%llu\n", state_usage->s2idle_##_name);\

}



define_show_state_s2idle_ull_function(usage);
@@ -550,7 +550,7 @@ static ssize_t show_driver_name(struct cpuidle_driver *drv, char *buf) 
	ssize_t ret;



	spin_lock(&cpuidle_driver_lock);

	ret = sprintf(buf, "%s\n", drv ? drv->name : "none");

	ret = sysfs_emit(buf, "%s\n", drv ? drv->name : "none");

	spin_unlock(&cpuidle_driver_lock);



	return ret;