2022-03-24 23:32:45

by Jakob Koschel

Subject: [PATCH] backlight: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <[email protected]>
---
drivers/video/backlight/backlight.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index 4ae6fae94ac2..c05380d7a09e 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -479,19 +479,18 @@ EXPORT_SYMBOL(backlight_device_register);
*/
struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
{
- bool found = false;
- struct backlight_device *bd;
+ struct backlight_device *bd = NULL, *iter;

mutex_lock(&backlight_dev_list_mutex);
- list_for_each_entry(bd, &backlight_dev_list, entry) {
- if (bd->props.type == type) {
- found = true;
+ list_for_each_entry(iter, &backlight_dev_list, entry) {
+ if (iter->props.type == type) {
+ bd = iter;
break;
}
}
mutex_unlock(&backlight_dev_list_mutex);

- return found ? bd : NULL;
+ return bd;
}
EXPORT_SYMBOL(backlight_device_get_by_type);


base-commit: f443e374ae131c168a065ea1748feac6b2e76613
--
2.25.1

2022-03-25 18:20:53

by Daniel Thompson

Subject: Re: [PATCH] backlight: replace usage of found with dedicated list iterator variable

On Thu, Mar 24, 2022 at 08:06:08AM +0100, Jakob Koschel wrote:
> To move the list iterator variable into the list_for_each_entry_*()
> macro in the future it should be avoided to use the list iterator
> variable after the loop body.
>
> To *never* use the list iterator variable after the loop it was
> concluded to use a separate iterator variable instead of a
> found boolean [1].
>
> This removes the need to use a found variable and simply checking if
> the variable was set, can determine if the break/goto was hit.
>
> Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
> Signed-off-by: Jakob Koschel <[email protected]>

Reviewed-by: Daniel Thompson <[email protected]>


Daniel.