Message-ID: <058018ea-b621-2c2f-d1a0-dc8dae0d5d83@nvidia.com>
Date:   Mon, 10 Jan 2022 23:33:05 -0800
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Subject: Re: [PATCH v2 21/28] gup: Convert gup_hugepte() to use a folio
Content-Language: en-US
To:     "Matthew Wilcox (Oracle)" <willy@infradead.org>, linux-mm@kvack.org
Cc:     Christoph Hellwig <hch@infradead.org>,
        William Kucharski <william.kucharski@oracle.com>,
        linux-kernel@vger.kernel.org, Jason Gunthorpe <jgg@ziepe.ca>
References: <20220110042406.499429-1-willy@infradead.org>
 <20220110042406.499429-22-willy@infradead.org>
From:   John Hubbard <jhubbard@nvidia.com>
In-Reply-To: <20220110042406.499429-22-willy@infradead.org>
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On 1/9/22 20:23, Matthew Wilcox (Oracle) wrote:
> There should be little to no effect from this patch; just removing
> uses of some old APIs.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---
>   mm/gup.c | 14 +++++++-------
>   1 file changed, 7 insertions(+), 7 deletions(-)

Reviewed-by: John Hubbard <jhubbard@nvidia.com>


thanks,
-- 
John Hubbard
NVIDIA

> 
> diff --git a/mm/gup.c b/mm/gup.c
> index 27cc097ec05d..250326458df6 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -2428,7 +2428,8 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
>   		       struct page **pages, int *nr)
>   {
>   	unsigned long pte_end;
> -	struct page *head, *page;
> +	struct page *page;
> +	struct folio *folio;
>   	pte_t pte;
>   	int refs;
>   
> @@ -2444,21 +2445,20 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
>   	/* hugepages are never "special" */
>   	VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
>   
> -	head = pte_page(pte);
> -	page = nth_page(head, (addr & (sz-1)) >> PAGE_SHIFT);
> +	page = nth_page(pte_page(pte), (addr & (sz - 1)) >> PAGE_SHIFT);
>   	refs = record_subpages(page, addr, end, pages + *nr);
>   
> -	head = try_grab_compound_head(head, refs, flags);
> -	if (!head)
> +	folio = try_grab_folio(page, refs, flags);
> +	if (!folio)
>   		return 0;
>   
>   	if (unlikely(pte_val(pte) != pte_val(*ptep))) {
> -		put_compound_head(head, refs, flags);
> +		gup_put_folio(folio, refs, flags);
>   		return 0;
>   	}
>   
>   	*nr += refs;
> -	SetPageReferenced(head);
> +	folio_set_referenced(folio);
>   	return 1;
>   }
>