2023-07-01 04:23:49

by zhangpeng (AS)

Subject: [PATCH v2 1/2] mm: use a folio in fault_dirty_shared_page()

From: ZhangPeng <[email protected]>

We can replace four implicit calls to compound_head() with one by using
folio.

Signed-off-by: ZhangPeng <[email protected]>
Reviewed-by: Sidhartha Kumar <[email protected]>
---
mm/memory.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index 765e5d8ed1f4..9a2f4dab872f 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2968,20 +2968,20 @@ static vm_fault_t fault_dirty_shared_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct address_space *mapping;
- struct page *page = vmf->page;
+ struct folio *folio = page_folio(vmf->page);
bool dirtied;
bool page_mkwrite = vma->vm_ops && vma->vm_ops->page_mkwrite;

- dirtied = set_page_dirty(page);
- VM_BUG_ON_PAGE(PageAnon(page), page);
+ dirtied = folio_mark_dirty(folio);
+ VM_BUG_ON_FOLIO(folio_test_anon(folio), folio);
/*
- * Take a local copy of the address_space - page.mapping may be zeroed
- * by truncate after unlock_page(). The address_space itself remains
- * pinned by vma->vm_file's reference. We rely on unlock_page()'s
+ * Take a local copy of the address_space - folio.mapping may be zeroed
+ * by truncate after folio_unlock(). The address_space itself remains
+ * pinned by vma->vm_file's reference. We rely on folio_unlock()'s
* release semantics to prevent the compiler from undoing this copying.
*/
- mapping = page_rmapping(page);
- unlock_page(page);
+ mapping = folio_raw_mapping(folio);
+ folio_unlock(folio);

if (!page_mkwrite)
file_update_time(vma->vm_file);
--
2.25.1

2023-07-02 00:25:06

by Matthew Wilcox

Subject: Re: [PATCH v2 1/2] mm: use a folio in fault_dirty_shared_page()

On Sat, Jul 01, 2023 at 11:28:52AM +0800, Peng Zhang wrote:
> From: ZhangPeng <[email protected]>
>
> We can replace four implicit calls to compound_head() with one by using
> folio.
>
> Signed-off-by: ZhangPeng <[email protected]>
> Reviewed-by: Sidhartha Kumar <[email protected]>

Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>