+ mm-constify-page_count-and-page_ref_count.patch added to -mm tree

+ mm-constify-page_count-and-page_ref_count.patch added to -mm tree

[akpm]

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@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(-)

--- 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@infradead.org 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