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Date:   Thu, 3 Aug 2023 16:33:46 +0300
From:   Mike Rapoport <rppt@kernel.org>
To:     Miaohe Lin <linmiaohe@huawei.com>
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/mm_init: use helper macro BITS_PER_LONG
Message-ID: <20230803133346.GH2607694@kernel.org>
References: <20230803114051.637709-1-linmiaohe@huawei.com>
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On Thu, Aug 03, 2023 at 07:40:51PM +0800, Miaohe Lin wrote:
> It's more readable to use helper macro BITS_PER_LONG. No functional
> change intended.
> 
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>  mm/mm_init.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/mm_init.c b/mm/mm_init.c
> index 66aca3f6accd..2f37dbb5ff9a 100644
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -79,7 +79,7 @@ void __init mminit_verify_pageflags_layout(void)
>  	int shift, width;
>  	unsigned long or_mask, add_mask;
>  
> -	shift = 8 * sizeof(unsigned long);
> +	shift = BITS_PER_LONG;
>  	width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH
>  		- LAST_CPUPID_SHIFT - KASAN_TAG_WIDTH - LRU_GEN_WIDTH - LRU_REFS_WIDTH;
>  	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
> @@ -1431,7 +1431,7 @@ static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned l
>  	usemapsize = roundup(zonesize, pageblock_nr_pages);
>  	usemapsize = usemapsize >> pageblock_order;
>  	usemapsize *= NR_PAGEBLOCK_BITS;
> -	usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
> +	usemapsize = roundup(usemapsize, BITS_PER_LONG);
>  
>  	return usemapsize / 8;

BITS_PER_BYTE instead of 8 here?

>  }

-- 
Sincerely yours,
Mike.