Re: [PATCH 2/3] hwmon: (coretemp) Remove unnecessary dependency of array index

From: Ashok Raj
Date: Thu Nov 30 2023 - 20:29:30 EST


On Mon, Nov 27, 2023 at 09:16:50PM +0800, Zhang Rui wrote:
> When sensor_device_attribute pointer is available, use container_of() to
> get the temp_data address.
>
> This removes the unnecessary dependency of cached index in
> pdata->core_data[].
>
> Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx>
> ---
> drivers/hwmon/coretemp.c | 15 +++++----------
> 1 file changed, 5 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
> index 6053ed3761c2..cef43fedbd58 100644
> --- a/drivers/hwmon/coretemp.c
> +++ b/drivers/hwmon/coretemp.c
> @@ -342,7 +342,7 @@ static ssize_t show_label(struct device *dev,
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> struct platform_data *pdata = dev_get_drvdata(dev);
> - struct temp_data *tdata = pdata->core_data[attr->index];
> + struct temp_data *tdata = container_of(attr, struct temp_data, sd_attrs[ATTR_LABEL]);
>
> if (tdata->is_pkg_data)
> return sprintf(buf, "Package id %u\n", pdata->pkg_id);
> @@ -355,8 +355,7 @@ static ssize_t show_crit_alarm(struct device *dev,
> {
> u32 eax, edx;
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> - struct platform_data *pdata = dev_get_drvdata(dev);
> - struct temp_data *tdata = pdata->core_data[attr->index];
> + struct temp_data *tdata = container_of(attr, struct temp_data, sd_attrs[ATTR_CRIT_ALARM]);
>
> mutex_lock(&tdata->update_lock);
> rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
> @@ -369,8 +368,7 @@ static ssize_t show_tjmax(struct device *dev,
> struct device_attribute *devattr, char *buf)
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> - struct platform_data *pdata = dev_get_drvdata(dev);
> - struct temp_data *tdata = pdata->core_data[attr->index];
> + struct temp_data *tdata = container_of(attr, struct temp_data, sd_attrs[ATTR_TJMAX]);
> int tjmax;
>
> mutex_lock(&tdata->update_lock);
> @@ -384,8 +382,7 @@ static ssize_t show_ttarget(struct device *dev,
> struct device_attribute *devattr, char *buf)
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> - struct platform_data *pdata = dev_get_drvdata(dev);
> - struct temp_data *tdata = pdata->core_data[attr->index];
> + struct temp_data *tdata = container_of(attr, struct temp_data, sd_attrs[ATTR_TTARGET]);
> int ttarget;
>
> mutex_lock(&tdata->update_lock);
> @@ -402,8 +399,7 @@ static ssize_t show_temp(struct device *dev,
> {
> u32 eax, edx;
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> - struct platform_data *pdata = dev_get_drvdata(dev);
> - struct temp_data *tdata = pdata->core_data[attr->index];
> + struct temp_data *tdata = container_of(attr, struct temp_data, sd_attrs[ATTR_TEMP]);
> int tjmax;
>
> mutex_lock(&tdata->update_lock);
> @@ -445,7 +441,6 @@ static int create_core_attrs(struct temp_data *tdata, struct device *dev,
> tdata->sd_attrs[i].dev_attr.attr.name = tdata->attr_name[i];
> tdata->sd_attrs[i].dev_attr.attr.mode = 0444;
> tdata->sd_attrs[i].dev_attr.show = rd_ptr[i];
> - tdata->sd_attrs[i].index = attr_no;

I was naively thinking if we could nuke that "index". I can see that used
in couple macros, but seems like we can lose it?

Completely untested.. and uncertain :-)


diff --git a/include/linux/hwmon-sysfs.h b/include/linux/hwmon-sysfs.h
index d896713359cd..4855893f9401 100644
--- a/include/linux/hwmon-sysfs.h
+++ b/include/linux/hwmon-sysfs.h
@@ -12,36 +12,35 @@

struct sensor_device_attribute{
struct device_attribute dev_attr;
- int index;
};
#define to_sensor_dev_attr(_dev_attr) \
container_of(_dev_attr, struct sensor_device_attribute, dev_attr)

-#define SENSOR_ATTR(_name, _mode, _show, _store, _index) \
+#define SENSOR_ATTR(_name, _mode, _show, _store) \
{ .dev_attr = __ATTR(_name, _mode, _show, _store), \
- .index = _index }
+ }

-#define SENSOR_ATTR_RO(_name, _func, _index) \
+#define SENSOR_ATTR_RO(_name, _func) \
SENSOR_ATTR(_name, 0444, _func##_show, NULL, _index)

-#define SENSOR_ATTR_RW(_name, _func, _index) \
- SENSOR_ATTR(_name, 0644, _func##_show, _func##_store, _index)
+#define SENSOR_ATTR_RW(_name, _func) \
+ SENSOR_ATTR(_name, 0644, _func##_show, _func##_store)

-#define SENSOR_ATTR_WO(_name, _func, _index) \
- SENSOR_ATTR(_name, 0200, NULL, _func##_store, _index)
+#define SENSOR_ATTR_WO(_name, _func) \
+ SENSOR_ATTR(_name, 0200, NULL, _func##_store)

-#define SENSOR_DEVICE_ATTR(_name, _mode, _show, _store, _index) \
+#define SENSOR_DEVICE_ATTR(_name, _mode, _show, _store) \
struct sensor_device_attribute sensor_dev_attr_##_name \
- = SENSOR_ATTR(_name, _mode, _show, _store, _index)
+ = SENSOR_ATTR(_name, _mode, _show, _store)

-#define SENSOR_DEVICE_ATTR_RO(_name, _func, _index) \
- SENSOR_DEVICE_ATTR(_name, 0444, _func##_show, NULL, _index)
+#define SENSOR_DEVICE_ATTR_RO(_name, _func) \
+ SENSOR_DEVICE_ATTR(_name, 0444, _func##_show, NULL)

#define SENSOR_DEVICE_ATTR_RW(_name, _func, _index) \
- SENSOR_DEVICE_ATTR(_name, 0644, _func##_show, _func##_store, _index)
+ SENSOR_DEVICE_ATTR(_name, 0644, _func##_show, _func##_store)

-#define SENSOR_DEVICE_ATTR_WO(_name, _func, _index) \
- SENSOR_DEVICE_ATTR(_name, 0200, NULL, _func##_store, _index)
+#define SENSOR_DEVICE_ATTR_WO(_name, _func) \
+ SENSOR_DEVICE_ATTR(_name, 0200, NULL, _func##_store)

struct sensor_device_attribute_2 {
struct device_attribute dev_attr;
diff --git a/drivers/gpu/drm/i915/i915_hwmon.c b/drivers/gpu/drm/i915/i915_hwmon.c
index 975da8e7f2a9..c3bbf2f7d6eb 100644
--- a/drivers/gpu/drm/i915/i915_hwmon.c
+++ b/drivers/gpu/drm/i915/i915_hwmon.c
@@ -239,7 +239,7 @@ hwm_power1_max_interval_store(struct device *dev,

static SENSOR_DEVICE_ATTR(power1_max_interval, 0664,
hwm_power1_max_interval_show,
- hwm_power1_max_interval_store, 0);
+ hwm_power1_max_interval_store);

static struct attribute *hwm_attributes[] = {
&sensor_dev_attr_power1_max_interval.dev_attr.attr,