The patch titled
Subject: mm/filemap: reinitialize folio->_mapcount directly
has been added to the -mm mm-unstable branch. Its filename is
mm-filemap-reinitialize-folio-_mapcount-directly.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-filemap-reinitialize-folio-_mapcount-directly.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/filemap: reinitialize folio->_mapcount directly
Date: Wed, 29 May 2024 13:19:03 +0200
Let's get rid of the page_mapcount_reset() call and simply reinitialize
folio->_mapcount directly.
Link: https://lkml.kernel.org/r/20240529111904.2069608-6-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/filemap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/filemap.c~mm-filemap-reinitialize-folio-_mapcount-directly
+++ a/mm/filemap.c
@@ -177,7 +177,7 @@ static void filemap_unaccount_folio(stru
* and we'd rather not leak it: if we're wrong,
* another bad page check should catch it later.
*/
- page_mapcount_reset(&folio->page);
+ atomic_set(&folio->_mapcount, -1);
folio_ref_sub(folio, mapcount);
}
}
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-memory-move-page_count-check-into-validate_page_before_insert.patch
mm-memory-cleanly-support-zeropage-in-vm_insert_page-vm_map_pages-and-vmf_insert_mixed.patch
mm-rmap-sanity-check-that-zeropages-are-not-passed-to-rmap.patch
mm-update-_mapcount-and-page_type-documentation.patch
mm-allow-reuse-of-the-lower-16-bit-of-the-page-type-with-an-actual-type.patch
mm-zsmalloc-use-a-proper-page-type.patch
mm-page_alloc-clear-pagebuddy-using-__clearpagebuddy-for-bad-pages.patch
mm-filemap-reinitialize-folio-_mapcount-directly.patch
mm-mm_init-initialize-page-_mapcount-directly-in-__init_single_page.patch
