[PATCH v9 07/96] mm: Constify page_count and page_ref_count

From: Matthew Wilcox (Oracle)
Date: Wed May 05 2021 - 11:15:54 EST

Now that compound_head() accepts a const struct page pointer, these two
functions can be marked as not modifying the page pointer they are passed.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx>
Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
include/linux/page_ref.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h
index f3318f34fc54..7ad46f45df39 100644
--- a/include/linux/page_ref.h
+++ b/include/linux/page_ref.h
@@ -62,12 +62,12 @@ static inline void __page_ref_unfreeze(struct page *page, int v)


-static inline int page_ref_count(struct page *page)
+static inline int page_ref_count(const struct page *page)
return atomic_read(&page->_refcount);

-static inline int page_count(struct page *page)
+static inline int page_count(const struct page *page)
return atomic_read(&compound_head(page)->_refcount);