Re: [PATCH 3/5] mm, slab: Remove unused kmalloc_size()

[Vlastimil Babka]

On 9/3/19 6:04 PM, Pengfei Li wrote:
> The size of kmalloc can be obtained from kmalloc_info[],
> so remove kmalloc_size() that will not be used anymore.
>
> Signed-off-by: Pengfei Li <lpf.vector@xxxxxxxxx>

Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
>   include/linux/slab.h | 20 --------------------
>   mm/slab.c            |  5 +++--
>   mm/slab_common.c     |  5 ++---
>   3 files changed, 5 insertions(+), 25 deletions(-)
>
> diff --git a/include/linux/slab.h b/include/linux/slab.h
> index 56c9c7eed34e..e773e5764b7b 100644
> --- a/include/linux/slab.h
> +++ b/include/linux/slab.h
> @@ -557,26 +557,6 @@ static __always_inline void *kmalloc(size_t size, gfp_t flags)
>   	return __kmalloc(size, flags);
>   }
>   
> -/*
> - * Determine size used for the nth kmalloc cache.
> - * return size or 0 if a kmalloc cache for that
> - * size does not exist
> - */
> -static __always_inline unsigned int kmalloc_size(unsigned int n)
> -{
> -#ifndef CONFIG_SLOB
> -	if (n > 2)
> -		return 1U << n;
> -
> -	if (n == 1 && KMALLOC_MIN_SIZE <= 32)
> -		return 96;
> -
> -	if (n == 2 && KMALLOC_MIN_SIZE <= 64)
> -		return 192;
> -#endif
> -	return 0;
> -}
> -
>   static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
>   {
>   #ifndef CONFIG_SLOB
> diff --git a/mm/slab.c b/mm/slab.c
> index c42b6211f42e..7bc4e90e1147 100644
> --- a/mm/slab.c
> +++ b/mm/slab.c
> @@ -1248,8 +1248,9 @@ void __init kmem_cache_init(void)
>   	 */
>   	kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE] = create_kmalloc_cache(
>   				kmalloc_info[INDEX_NODE].name[KMALLOC_NORMAL],
> -				kmalloc_size(INDEX_NODE), ARCH_KMALLOC_FLAGS,
> -				0, kmalloc_size(INDEX_NODE));
> +				kmalloc_info[INDEX_NODE].size,
> +				ARCH_KMALLOC_FLAGS, 0,
> +				kmalloc_info[INDEX_NODE].size);
>   	slab_state = PARTIAL_NODE;
>   	setup_kmalloc_cache_index_table();
>   
> diff --git a/mm/slab_common.c b/mm/slab_common.c
> index 002e16673581..8b542cfcc4f2 100644
> --- a/mm/slab_common.c
> +++ b/mm/slab_common.c
> @@ -1239,11 +1239,10 @@ void __init create_kmalloc_caches(slab_flags_t flags)
>   		struct kmem_cache *s = kmalloc_caches[KMALLOC_NORMAL][i];
>   
>   		if (s) {
> -			unsigned int size = kmalloc_size(i);
> -
>   			kmalloc_caches[KMALLOC_DMA][i] = create_kmalloc_cache(
>   				kmalloc_info[i].name[KMALLOC_DMA],
> -				size, SLAB_CACHE_DMA | flags, 0, 0);
> +				kmalloc_info[i].size,
> +				SLAB_CACHE_DMA | flags, 0, 0);
>   		}
>   	}
>   #endif