+ mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook.patch added to mm-unstable branch

+ mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/page_alloc: move set_page_refcounted() to callers of post_alloc_hook()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook.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: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm/page_alloc: move set_page_refcounted() to callers of post_alloc_hook()
Date: Mon, 25 Nov 2024 21:01:36 +0000

In preparation for allocating frozen pages, stop initialising the page
refcount in post_alloc_hook().

Link: https://lkml.kernel.org/r/20241125210149.2976098-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Mel Gorman <mgorman@techsinguularity.net>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/compaction.c |    2 ++
 mm/internal.h   |    3 +--
 mm/page_alloc.c |    3 ++-
 3 files changed, 5 insertions(+), 3 deletions(-)

--- a/mm/compaction.c~mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook
+++ a/mm/compaction.c
@@ -83,6 +83,7 @@ static inline bool is_via_compact_memory
 static struct page *mark_allocated_noprof(struct page *page, unsigned int order, gfp_t gfp_flags)
 {
 	post_alloc_hook(page, order, __GFP_MOVABLE);
+	set_page_refcounted(page);
 	return page;
 }
 #define mark_allocated(...)	alloc_hooks(mark_allocated_noprof(__VA_ARGS__))
@@ -1868,6 +1869,7 @@ again:
 	dst = (struct folio *)freepage;
 
 	post_alloc_hook(&dst->page, order, __GFP_MOVABLE);
+	set_page_refcounted(&dst->page);
 	if (order)
 		prep_compound_page(&dst->page, order);
 	cc->nr_freepages -= 1 << order;
--- a/mm/internal.h~mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook
+++ a/mm/internal.h
@@ -735,8 +735,7 @@ static inline void prep_compound_tail(st
 
 extern void prep_compound_page(struct page *page, unsigned int order);
 
-extern void post_alloc_hook(struct page *page, unsigned int order,
-					gfp_t gfp_flags);
+void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags);
 extern bool free_pages_prepare(struct page *page, unsigned int order);
 
 extern int user_min_free_kbytes;
--- a/mm/page_alloc.c~mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook
+++ a/mm/page_alloc.c
@@ -1506,7 +1506,6 @@ inline void post_alloc_hook(struct page
 	int i;
 
 	set_page_private(page, 0);
-	set_page_refcounted(page);
 
 	arch_alloc_page(page, order);
 	debug_pagealloc_map_pages(page, 1 << order);
@@ -1562,6 +1561,7 @@ static void prep_new_page(struct page *p
 							unsigned int alloc_flags)
 {
 	post_alloc_hook(page, order, gfp_flags);
+	set_page_refcounted(page);
 
 	if (order && (gfp_flags & __GFP_COMP))
 		prep_compound_page(page, order);
@@ -6358,6 +6358,7 @@ static void split_free_pages(struct list
 			int i;
 
 			post_alloc_hook(page, order, __GFP_MOVABLE);
+			set_page_refcounted(page);
 			if (!order)
 				continue;
 
_

Patches currently in -mm which might be from willy@infradead.org are

mm-page_alloc-cache-page_zone-result-in-free_unref_page.patch
mm-make-alloc_pages_mpol-static.patch
mm-page_alloc-export-free_frozen_pages-instead-of-free_unref_page.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-prep_new_page.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-get_page_from_freelist.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_cpuset_fallback.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_may_oom.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_direct_compact.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_direct_reclaim.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_slowpath.patch
mm-page_alloc-move-set_page_refcounted-to-end-of-__alloc_pages.patch
mm-page_alloc-add-__alloc_frozen_pages.patch
mm-mempolicy-add-alloc_frozen_pages.patch
slab-allocate-frozen-pages.patch