Modified the function fns to resolve a calculation error by:
1. Reducing n first.
2. Adding 1 at the end to get the correct index.

This commit improves the accuracy and reliability of the code.

Signed-off-by: Chin-Chun Chen <chinchunchen2001@gmail.com>
---
 include/linux/bitops.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 2ba557e067fe..2457610f74eb 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -258,8 +258,8 @@ static inline unsigned long fns(unsigned long word, unsigned int n)
 
 	while (word) {
 		bit = __ffs(word);
-		if (n-- == 0)
-			return bit;
+		if (--n == 0)
+			return bit + 1;
 		__clear_bit(bit, &word);
 	}
 

base-commit: 8f2c057754b25075aa3da132cd4fd4478cdab854
-- 
2.40.1

On 4/12/24 10:28 PM, Chin-Chun Chen wrote:
> Modified the function fns to resolve a calculation error by:
> 1. Reducing n first.
> 2. Adding 1 at the end to get the correct index.
> 
> This commit improves the accuracy and reliability of the code.
> 
> Signed-off-by: Chin-Chun Chen <chinchunchen2001@gmail.com>
> ---
>  include/linux/bitops.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index 2ba557e067fe..2457610f74eb 100644
> --- a/include/linux/bitops.h
> +++ b/include/linux/bitops.h
> @@ -258,8 +258,8 @@ static inline unsigned long fns(unsigned long word, unsigned int n)
>  
>  	while (word) {
>  		bit = __ffs(word);
> -		if (n-- == 0)
> -			return bit;
> +		if (--n == 0)
> +			return bit + 1;
>  		__clear_bit(bit, &word);
>  	}
>  
> 
> base-commit: 8f2c057754b25075aa3da132cd4fd4478cdab854

Hi,

Please send your patch to some maintainer.
People don't browse the mailing list for patches to pick up.


-- 
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