Re: [PATCH v1 12/14] extcon: Use sizeof(*pointer) instead of sizeof(type)

[Chanwoo Choi]

On 23. 3. 22. 23:40, Andy Shevchenko wrote:
> It is preferred to use sizeof(*pointer) instead of sizeof(type).
> The type of the variable can change and one needs not change
> the former (unlike the latter). No functional change intended.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
>  drivers/extcon/extcon.c | 17 ++++++-----------
>  1 file changed, 6 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
> index 0e04ea185c26..b3f038639cd6 100644
> --- a/drivers/extcon/extcon.c
> +++ b/drivers/extcon/extcon.c
> @@ -1099,9 +1099,7 @@ static int extcon_alloc_cables(struct extcon_dev *edev)
>  	if (!edev->max_supported)
>  		return 0;
>  
> -	edev->cables = kcalloc(edev->max_supported,
> -			       sizeof(struct extcon_cable),
> -			       GFP_KERNEL);
> +	edev->cables = kcalloc(edev->max_supported, sizeof(*edev->cables), GFP_KERNEL);

Even if there are strictly not limitation of the number of maximum char
at the one line, But, I recommend to keep the 80 char at the one line
for the readability as following.

-       edev->cables = kcalloc(edev->max_supported, sizeof(*edev->cables), GFP_KERNEL);
+       edev->cables = kcalloc(edev->max_supported,
+                       sizeof(*edev->cables), GFP_KERNEL);


>  	if (!edev->cables)
>  		return -ENOMEM;
>  
> @@ -1160,14 +1158,12 @@ static int extcon_alloc_muex(struct extcon_dev *edev)
>  	for (index = 0; edev->mutually_exclusive[index]; index++)
>  		;
>  
> -	edev->attrs_muex = kcalloc(index + 1,
> -				   sizeof(struct attribute *),
> +	edev->attrs_muex = kcalloc(index + 1, sizeof(*edev->attrs_muex),
>  				   GFP_KERNEL);
>  	if (!edev->attrs_muex)
>  		return -ENOMEM;
>  
> -	edev->d_attrs_muex = kcalloc(index,
> -				     sizeof(struct device_attribute),
> +	edev->d_attrs_muex = kcalloc(index, sizeof(*edev->d_attrs_muex),
>  				     GFP_KERNEL);
>  	if (!edev->d_attrs_muex) {
>  		kfree(edev->attrs_muex);
> @@ -1213,8 +1209,8 @@ static int extcon_alloc_groups(struct extcon_dev *edev)
>  		return 0;
>  
>  	edev->extcon_dev_type.groups = kcalloc(edev->max_supported + 2,
> -			sizeof(struct attribute_group *),
> -			GFP_KERNEL);
> +					       sizeof(*edev->extcon_dev_type.groups),
> +					       GFP_KERNEL);

ditto.

        edev->extcon_dev_type.groups = kcalloc(edev->max_supported + 2,
-                                              sizeof(*edev->extcon_dev_type.groups),
-                                              GFP_KERNEL);
+                                      sizeof(*edev->extcon_dev_type.groups),
+                                      GFP_KERNEL);


>  	if (!edev->extcon_dev_type.groups)
>  		return -ENOMEM;
>  
> @@ -1298,8 +1294,7 @@ int extcon_dev_register(struct extcon_dev *edev)
>  
>  	spin_lock_init(&edev->lock);
>  	if (edev->max_supported) {
> -		edev->nh = kcalloc(edev->max_supported, sizeof(*edev->nh),
> -				GFP_KERNEL);
> +		edev->nh = kcalloc(edev->max_supported, sizeof(*edev->nh), GFP_KERNEL);

-               edev->nh = kcalloc(edev->max_supported, sizeof(*edev->nh), GFP_KERNEL);
+               edev->nh = kcalloc(edev->max_supported,
+                               sizeof(*edev->nh), GFP_KERNEL);


>  		if (!edev->nh) {
>  			ret = -ENOMEM;
>  			goto err_alloc_nh;

-- 
Best Regards,
Samsung Electronics
Chanwoo Choi