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Message-ID: <590d3fd8-54a8-e2c8-33ae-5e2f6d03abe4@redhat.com>
Date:   Thu, 3 Aug 2023 15:08:54 +0200
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Subject: Re: [PATCH] mm/mm_init: use helper macro BITS_PER_LONG
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To:     Miaohe Lin <linmiaohe@huawei.com>, akpm@linux-foundation.org,
        rppt@kernel.org
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20230803114051.637709-1-linmiaohe@huawei.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20230803114051.637709-1-linmiaohe@huawei.com>
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On 03.08.23 13:40, 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;
>   }

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb