2023-09-15 17:21:16

by Yajun Deng

Subject: [PATCH] mm/rmap: convert __page_check_anon_rmap() to folio

The parameter page in __page_check_anon_rmap() is redundant. Remove it,
and convert __page_check_anon_rmap() to __folio_check_anon_rmap().

Signed-off-by: Yajun Deng <[email protected]>
---
mm/rmap.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/mm/rmap.c b/mm/rmap.c
index 789a2beb8b3a..520607f4d91c 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1154,13 +1154,12 @@ static void __folio_set_anon(struct folio *folio, struct vm_area_struct *vma,
}

/**
- * __page_check_anon_rmap - sanity check anonymous rmap addition
+ * __folio_check_anon_rmap - sanity check anonymous rmap addition
* @folio: The folio containing @page.
- * @page: the page to check the mapping of
* @vma: the vm area in which the mapping is added
* @address: the user virtual address mapped
*/
-static void __page_check_anon_rmap(struct folio *folio, struct page *page,
+static void __folio_check_anon_rmap(struct folio *folio,
struct vm_area_struct *vma, unsigned long address)
{
/*
@@ -1176,8 +1175,8 @@ static void __page_check_anon_rmap(struct folio *folio, struct page *page,
*/
VM_BUG_ON_FOLIO(folio_anon_vma(folio)->root != vma->anon_vma->root,
folio);
- VM_BUG_ON_PAGE(page_to_pgoff(page) != linear_page_index(vma, address),
- page);
+ VM_BUG_ON_FOLIO(folio_pgoff(folio) != linear_page_index(vma, address),
+ folio);
}

/**
@@ -1245,7 +1244,7 @@ void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma,
__folio_set_anon(folio, vma, address,
!!(flags & RMAP_EXCLUSIVE));
} else if (likely(!folio_test_ksm(folio))) {
- __page_check_anon_rmap(folio, page, vma, address);
+ __folio_check_anon_rmap(folio, vma, address);
}
if (flags & RMAP_EXCLUSIVE)
SetPageAnonExclusive(page);
--
2.25.1

2023-09-15 20:40:53

by Matthew Wilcox

Subject: Re: [PATCH] mm/rmap: convert __page_check_anon_rmap() to folio

On Fri, Sep 15, 2023 at 06:17:31PM +0800, Yajun Deng wrote:
> @@ -1176,8 +1175,8 @@ static void __page_check_anon_rmap(struct folio *folio, struct page *page,
> */
> VM_BUG_ON_FOLIO(folio_anon_vma(folio)->root != vma->anon_vma->root,
> folio);
> - VM_BUG_ON_PAGE(page_to_pgoff(page) != linear_page_index(vma, address),
> - page);
> + VM_BUG_ON_FOLIO(folio_pgoff(folio) != linear_page_index(vma, address),
> + folio);

No, this is not equivalent. You haven't hit any problems testing it
because you don't have large anonymous folios.

2023-09-16 00:02:47

by David Hildenbrand

Subject: Re: [PATCH] mm/rmap: convert __page_check_anon_rmap() to folio

On 15.09.23 15:49, Matthew Wilcox wrote:
> On Fri, Sep 15, 2023 at 06:17:31PM +0800, Yajun Deng wrote:
>> @@ -1176,8 +1175,8 @@ static void __page_check_anon_rmap(struct folio *folio, struct page *page,
>> */
>> VM_BUG_ON_FOLIO(folio_anon_vma(folio)->root != vma->anon_vma->root,
>> folio);
>> - VM_BUG_ON_PAGE(page_to_pgoff(page) != linear_page_index(vma, address),
>> - page);
>> + VM_BUG_ON_FOLIO(folio_pgoff(folio) != linear_page_index(vma, address),
>> + folio);
>
> No, this is not equivalent. You haven't hit any problems testing it
> because you don't have large anonymous folios.

Right, the address would have to be adjusted as well by the caller.

--
Cheers,

David / dhildenb