The patch titled
Subject: mm: constify page_count and page_ref_count
has been added to the -mm tree. Its filename is
mm-constify-page_count-and-page_ref_count.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-constify-page_count-and-page_ref_count.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-constify-page_count-and-page_ref_count.patch
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
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@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/page_ref.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- 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);
}
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-make-__dump_page-static.patch
mm-debug-factor-pagepoisoned-out-of-__dump_page.patch
mm-page_owner-constify-dump_page_owner.patch
mm-make-compound_head-const-preserving.patch
mm-constify-get_pfnblock_flags_mask-and-get_pfnblock_migratetype.patch
mm-constify-page_count-and-page_ref_count.patch
