[PATCH 32/44] nodemask: use min() instead of min_t()

david.laight.linux@gmail.com posted 44 patches 1 week, 5 days ago
There is a newer version of this series
[PATCH 32/44] nodemask: use min() instead of min_t()
Posted by david.laight.linux@gmail.com 1 week, 5 days ago
From: David Laight <david.laight.linux@gmail.com>

min_t(unsigned int, a, b) casts an 'unsigned long' to 'unsigned int'.
Use min(a, b) instead as it promotes any 'unsigned int' to 'unsigned long'
and so cannot discard significant bits.

In this case the 'unsigned long' value is small enough that the result
is ok.

Detected by an extra check added to min_t().

Signed-off-by: David Laight <david.laight.linux@gmail.com>
---
 include/linux/nodemask.h | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
index 7ad1f5c7407e..bd38648c998d 100644
--- a/include/linux/nodemask.h
+++ b/include/linux/nodemask.h
@@ -245,18 +245,18 @@ static __always_inline int __nodes_weight(const nodemask_t *srcp, unsigned int n
 }
 
 /* FIXME: better would be to fix all architectures to never return
-          > MAX_NUMNODES, then the silly min_ts could be dropped. */
+          > MAX_NUMNODES, then the silly min()s could be dropped. */
 
 #define first_node(src) __first_node(&(src))
 static __always_inline unsigned int __first_node(const nodemask_t *srcp)
 {
-	return min_t(unsigned int, MAX_NUMNODES, find_first_bit(srcp->bits, MAX_NUMNODES));
+	return min(MAX_NUMNODES, find_first_bit(srcp->bits, MAX_NUMNODES));
 }
 
 #define next_node(n, src) __next_node((n), &(src))
 static __always_inline unsigned int __next_node(int n, const nodemask_t *srcp)
 {
-	return min_t(unsigned int, MAX_NUMNODES, find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
+	return min(MAX_NUMNODES, find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
 }
 
 /*
@@ -293,8 +293,7 @@ static __always_inline void init_nodemask_of_node(nodemask_t *mask, int node)
 #define first_unset_node(mask) __first_unset_node(&(mask))
 static __always_inline unsigned int __first_unset_node(const nodemask_t *maskp)
 {
-	return min_t(unsigned int, MAX_NUMNODES,
-			find_first_zero_bit(maskp->bits, MAX_NUMNODES));
+	return min(MAX_NUMNODES, find_first_zero_bit(maskp->bits, MAX_NUMNODES));
 }
 
 #define NODE_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(MAX_NUMNODES)
-- 
2.39.5
Re: [PATCH 32/44] nodemask: use min() instead of min_t()
Posted by Yury Norov 1 week, 4 days ago
On Wed, Nov 19, 2025 at 10:41:28PM +0000, david.laight.linux@gmail.com wrote:
> From: David Laight <david.laight.linux@gmail.com>
> 
> min_t(unsigned int, a, b) casts an 'unsigned long' to 'unsigned int'.
> Use min(a, b) instead as it promotes any 'unsigned int' to 'unsigned long'
> and so cannot discard significant bits.
> 
> In this case the 'unsigned long' value is small enough that the result
> is ok.
> 
> Detected by an extra check added to min_t().
> 
> Signed-off-by: David Laight <david.laight.linux@gmail.com>

Applied, thanks.

> ---
>  include/linux/nodemask.h | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
> index 7ad1f5c7407e..bd38648c998d 100644
> --- a/include/linux/nodemask.h
> +++ b/include/linux/nodemask.h
> @@ -245,18 +245,18 @@ static __always_inline int __nodes_weight(const nodemask_t *srcp, unsigned int n
>  }
>  
>  /* FIXME: better would be to fix all architectures to never return
> -          > MAX_NUMNODES, then the silly min_ts could be dropped. */
> +          > MAX_NUMNODES, then the silly min()s could be dropped. */
>  
>  #define first_node(src) __first_node(&(src))
>  static __always_inline unsigned int __first_node(const nodemask_t *srcp)
>  {
> -	return min_t(unsigned int, MAX_NUMNODES, find_first_bit(srcp->bits, MAX_NUMNODES));
> +	return min(MAX_NUMNODES, find_first_bit(srcp->bits, MAX_NUMNODES));
>  }
>  
>  #define next_node(n, src) __next_node((n), &(src))
>  static __always_inline unsigned int __next_node(int n, const nodemask_t *srcp)
>  {
> -	return min_t(unsigned int, MAX_NUMNODES, find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
> +	return min(MAX_NUMNODES, find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
>  }
>  
>  /*
> @@ -293,8 +293,7 @@ static __always_inline void init_nodemask_of_node(nodemask_t *mask, int node)
>  #define first_unset_node(mask) __first_unset_node(&(mask))
>  static __always_inline unsigned int __first_unset_node(const nodemask_t *maskp)
>  {
> -	return min_t(unsigned int, MAX_NUMNODES,
> -			find_first_zero_bit(maskp->bits, MAX_NUMNODES));
> +	return min(MAX_NUMNODES, find_first_zero_bit(maskp->bits, MAX_NUMNODES));
>  }
>  
>  #define NODE_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(MAX_NUMNODES)
> -- 
> 2.39.5
>