Re: [PATCH v9 08/10] mm/vmalloc: extract vm_shift() to consolidate mapping shift selection

[Uladzislau Rezki]

On Wed, Sep 23, 2026 at 02:28:30PM +0800, Wen Jiang wrote:
> Extract the vmalloc mapping shift selection from
> __vmalloc_node_range_noprof() into vm_shift(), preparing for reuse by the
> vmap batching path.
> 
> No functional change.
> 
> Suggested-by: Dev Jain <dev.jain@xxxxxxx>
> Signed-off-by: Wen Jiang <jiangwen6@xxxxxxxxxx>
> Tested-by: Xueyuan Chen <xueyuan.chen21@xxxxxxxxx>
> Tested-by: Leo Yan <leo.yan@xxxxxxx>
> ---
>  mm/vmalloc.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 6e0dec73107a7..a43965016eb4d 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -3568,6 +3568,14 @@ void vunmap(const void *addr)
>  }
>  EXPORT_SYMBOL(vunmap);
>  
> +static inline unsigned int vm_shift(pgprot_t prot, unsigned long size)
> +{
> +	if (arch_vmap_pmd_supported(prot) && size >= PMD_SIZE)
> +		return PMD_SHIFT;
> +
> +	return arch_vmap_pte_supported_shift(size);
> +}
> +
>  /**
>   * vmap - map an array of pages into virtually contiguous space
>   * @pages: array of page pointers
> @@ -4079,11 +4087,7 @@ void *__vmalloc_node_range_noprof(unsigned long size, unsigned long align,
>  		 * supporting them.
>  		 */
>  
> -		if (arch_vmap_pmd_supported(prot) && size >= PMD_SIZE)
> -			shift = PMD_SHIFT;
> -		else
> -			shift = arch_vmap_pte_supported_shift(size);
> -
> +		shift = vm_shift(prot, size);
>  		align = max(original_align, 1UL << shift);
>  	}
>  
> -- 
> 2.34.1
> 
Reviewed-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>

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Uladzislau Rezki