diff mbox series

[156/192] mm: constify page_count and page_ref_count

Message ID 20210629024125.8tPyrqCyS%akpm@linux-foundation.org (mailing list archive)
State New
Headers show
Series [001/192] mm/gup: fix try_grab_compound_head() race with split_huge_page() | expand

Commit Message

Andrew Morton June 29, 2021, 2:41 a.m. UTC 
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm: constify page_count and page_ref_count

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.

Link: https://lkml.kernel.org/r/20210416231531.2521383-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/page_ref.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/include/linux/page_ref.h~mm-constify-page_count-and-page_ref_count
+++ a/include/linux/page_ref.h
@@ -62,12 +62,12 @@  static inline void __page_ref_unfreeze(s
 
 #endif
 
-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);
 }