+ mm-page_owner-use-order-instead-of-nr-in-split_page_owner.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

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The patch titled
     Subject: mm/page_owner: use order instead of nr in split_page_owner()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-page_owner-use-order-instead-of-nr-in-split_page_owner.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_owner-use-order-instead-of-nr-in-split_page_owner.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: Zi Yan <ziy@nvidia.com>
Subject: mm/page_owner: use order instead of nr in split_page_owner()
Date: Mon, 3 Apr 2023 16:18:34 -0400

We do not have non power of two pages, using nr is error prone if nr is
not power-of-two.  Use page order instead.

Link: https://lkml.kernel.org/r/20230403201839.4097845-3-zi.yan@sent.com
Signed-off-by: Zi Yan <ziy@nvidia.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/page_owner.h |    8 ++++----
 mm/huge_memory.c           |    2 +-
 mm/page_alloc.c            |    4 ++--
 mm/page_owner.c            |    3 ++-
 4 files changed, 9 insertions(+), 8 deletions(-)

--- a/include/linux/page_owner.h~mm-page_owner-use-order-instead-of-nr-in-split_page_owner
+++ a/include/linux/page_owner.h
@@ -11,7 +11,7 @@ extern struct page_ext_operations page_o
 extern void __reset_page_owner(struct page *page, unsigned short order);
 extern void __set_page_owner(struct page *page,
 			unsigned short order, gfp_t gfp_mask);
-extern void __split_page_owner(struct page *page, unsigned int nr);
+extern void __split_page_owner(struct page *page, int order);
 extern void __folio_copy_owner(struct folio *newfolio, struct folio *old);
 extern void __set_page_owner_migrate_reason(struct page *page, int reason);
 extern void __dump_page_owner(const struct page *page);
@@ -31,10 +31,10 @@ static inline void set_page_owner(struct
 		__set_page_owner(page, order, gfp_mask);
 }
 
-static inline void split_page_owner(struct page *page, unsigned int nr)
+static inline void split_page_owner(struct page *page, int order)
 {
 	if (static_branch_unlikely(&page_owner_inited))
-		__split_page_owner(page, nr);
+		__split_page_owner(page, order);
 }
 static inline void folio_copy_owner(struct folio *newfolio, struct folio *old)
 {
@@ -60,7 +60,7 @@ static inline void set_page_owner(struct
 {
 }
 static inline void split_page_owner(struct page *page,
-			unsigned short order)
+			int order)
 {
 }
 static inline void folio_copy_owner(struct folio *newfolio, struct folio *folio)
--- a/mm/huge_memory.c~mm-page_owner-use-order-instead-of-nr-in-split_page_owner
+++ a/mm/huge_memory.c
@@ -2557,7 +2557,7 @@ static void __split_huge_page(struct pag
 	unlock_page_lruvec(lruvec);
 	/* Caller disabled irqs, so they are still disabled here */
 
-	split_page_owner(head, nr);
+	split_page_owner(head, order);
 
 	/* See comment in __split_huge_page_tail() */
 	if (PageAnon(head)) {
--- a/mm/page_alloc.c~mm-page_owner-use-order-instead-of-nr-in-split_page_owner
+++ a/mm/page_alloc.c
@@ -2780,7 +2780,7 @@ void split_page(struct page *page, unsig
 
 	for (i = 1; i < (1 << order); i++)
 		set_page_refcounted(page + i);
-	split_page_owner(page, 1 << order);
+	split_page_owner(page, order);
 	split_page_memcg(page, order);
 }
 EXPORT_SYMBOL_GPL(split_page);
@@ -4996,7 +4996,7 @@ static void *make_alloc_exact(unsigned l
 		struct page *page = virt_to_page((void *)addr);
 		struct page *last = page + nr;
 
-		split_page_owner(page, 1 << order);
+		split_page_owner(page, order);
 		split_page_memcg(page, order);
 		while (page < --last)
 			set_page_refcounted(last);
--- a/mm/page_owner.c~mm-page_owner-use-order-instead-of-nr-in-split_page_owner
+++ a/mm/page_owner.c
@@ -211,11 +211,12 @@ void __set_page_owner_migrate_reason(str
 	page_ext_put(page_ext);
 }
 
-void __split_page_owner(struct page *page, unsigned int nr)
+void __split_page_owner(struct page *page, int order)
 {
 	int i;
 	struct page_ext *page_ext = page_ext_get(page);
 	struct page_owner *page_owner;
+	unsigned int nr = 1 << order;
 
 	if (unlikely(!page_ext))
 		return;
_

Patches currently in -mm which might be from ziy@nvidia.com are

mm-memcg-use-order-instead-of-nr-in-split_page_memcg.patch
mm-page_owner-use-order-instead-of-nr-in-split_page_owner.patch
mm-memcg-make-memcg-huge-page-split-support-any-order-split.patch
mm-page_owner-add-support-for-splitting-to-any-order-in-split-page_owner.patch
mm-thp-split-huge-page-to-any-lower-order-pages.patch
mm-truncate-split-huge-page-cache-page-to-a-non-zero-order-if-possible.patch
mm-huge_memory-enable-debugfs-to-split-huge-pages-to-any-order.patch