Re: [PATCH] mm/hugetlb: use some helper functions to cleanup code

[Mike Kravetz <mike.kravetz@oracle.com>]

On 2/9/21 10:53 PM, Miaohe Lin wrote:
> We could use pages_per_huge_page to get the number of pages per hugepage,
> use get_hstate_idx to calculate hstate index, and use hstate_is_gigantic
> to check if a hstate is gigantic to make code more succinct.
> 
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>

These are all straight forward substitutions of open coded calculations
with the appropriate helper routine.

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

> ---
>  fs/hugetlbfs/inode.c | 2 +-
>  mm/hugetlb.c         | 6 +++---
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
> index 701c82c36138..c262566f7c5d 100644
> --- a/fs/hugetlbfs/inode.c
> +++ b/fs/hugetlbfs/inode.c
> @@ -1435,7 +1435,7 @@ static int get_hstate_idx(int page_size_log)
>  
>  	if (!h)
>  		return -1;
> -	return h - hstates;
> +	return hstate_index(h);
>  }
>  
>  /*
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 8f6c98096476..da347047ea10 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -1271,7 +1271,7 @@ static void free_gigantic_page(struct page *page, unsigned int order)
>  static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
>  		int nid, nodemask_t *nodemask)
>  {
> -	unsigned long nr_pages = 1UL << huge_page_order(h);
> +	unsigned long nr_pages = pages_per_huge_page(h);
>  	if (nid == NUMA_NO_NODE)
>  		nid = numa_mem_id();
>  
> @@ -3262,10 +3262,10 @@ static int __init hugepages_setup(char *s)
>  
>  	/*
>  	 * Global state is always initialized later in hugetlb_init.
> -	 * But we need to allocate >= MAX_ORDER hstates here early to still
> +	 * But we need to allocate gigantic hstates here early to still
>  	 * use the bootmem allocator.
>  	 */
> -	if (hugetlb_max_hstate && parsed_hstate->order >= MAX_ORDER)
> +	if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate))
>  		hugetlb_hstate_alloc_pages(parsed_hstate);
>  
>  	last_mhp = mhp;
>