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Message-ID: <451b1e7c-3669-7b55-7daa-9a2911aaf5c5@redhat.com>
Date:   Tue, 20 Jun 2023 17:23:59 +0200
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Subject: Re: [PATCH v2 4/8] mm/gup: Cleanup next_page handling
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To:     Peter Xu <peterx@redhat.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Cc:     Andrea Arcangeli <aarcange@redhat.com>,
        Mike Rapoport <rppt@kernel.org>,
        Matthew Wilcox <willy@infradead.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        John Hubbard <jhubbard@nvidia.com>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        James Houghton <jthoughton@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Lorenzo Stoakes <lstoakes@gmail.com>,
        Hugh Dickins <hughd@google.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Jason Gunthorpe <jgg@nvidia.com>
References: <20230619231044.112894-1-peterx@redhat.com>
 <20230619231044.112894-5-peterx@redhat.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20230619231044.112894-5-peterx@redhat.com>
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Precedence: bulk

On 20.06.23 01:10, Peter Xu wrote:
> The only path that doesn't use generic "**pages" handling is the gate vma.
> Make it use the same path, meanwhile tune the next_page label upper to
> cover "**pages" handling.  This prepares for THP handling for "**pages".
> 
> Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>   mm/gup.c | 7 +++----
>   1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/mm/gup.c b/mm/gup.c
> index 9fc9271cba8d..4a00d609033e 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -1124,7 +1124,7 @@ static long __get_user_pages(struct mm_struct *mm,
>   			if (!vma && in_gate_area(mm, start)) {
>   				ret = get_gate_page(mm, start & PAGE_MASK,
>   						gup_flags, &vma,
> -						pages ? &pages[i] : NULL);
> +						pages ? &page : NULL);
>   				if (ret)
>   					goto out;
>   				ctx.page_mask = 0;
> @@ -1194,19 +1194,18 @@ static long __get_user_pages(struct mm_struct *mm,
>   				ret = PTR_ERR(page);
>   				goto out;
>   			}
> -
> -			goto next_page;
>   		} else if (IS_ERR(page)) {
>   			ret = PTR_ERR(page);
>   			goto out;
>   		}
> +next_page:
>   		if (pages) {
>   			pages[i] = page;
>   			flush_anon_page(vma, page, start);
>   			flush_dcache_page(page);
>   			ctx.page_mask = 0;
>   		}
> -next_page:
> +
>   		page_increm = 1 + (~(start >> PAGE_SHIFT) & ctx.page_mask);
>   		if (page_increm > nr_pages)
>   			page_increm = nr_pages;

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

-- 
Cheers,

David / dhildenb