[PATCH 11/11] mm/mm_init: move pageblock migratetype init to memmap helpers

[Muchun Song]

ZONE_DEVICE memmap initialization already initializes pageblock
migratetype after all struct pages have been initialized, while hugetlb
bootmem folios have their own duplicate bootmem-specific initialization.

Move the MIGRATE_MOVABLE pageblock initialization into the frozen memmap
initialization helpers instead. This makes memmap_init_page_frozen()
initialize the pageblock for single pages and
memmap_init_compound_page_frozen() initialize the whole range for compound
pages, so the ZONE_DEVICE and hugetlb bootmem paths can share the same
initialization.

The old hugetlb_bootmem_init_migratetype() skipped CMA folios via
folio_test_hugetlb_cma(), but the shared helper always initializes
pageblocks as MIGRATE_MOVABLE. This is safe because cma_activate_area()
later overrides the migratetype for CMA pageblocks.

Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
 mm/hugetlb.c | 25 -------------------------
 mm/mm_init.c | 11 ++++++-----
 2 files changed, 6 insertions(+), 30 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ee47a3b09df3..5dfe9091b5ca 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3222,30 +3222,6 @@ static bool __init alloc_bootmem_huge_page(struct hstate *h, int nid)
 	return true;
 }
 
-/*
- * memblock-allocated pageblocks might not have the migrate type set
- * if marked with the 'noinit' flag. Set it to the default (MIGRATE_MOVABLE)
- * here, or MIGRATE_CMA if this was a page allocated through an early CMA
- * reservation.
- *
- * In case of vmemmap optimized folios, the tail vmemmap pages are mapped
- * read-only, but that's ok - for sparse vmemmap this does not write to
- * the page structure.
- */
-static void __init hugetlb_bootmem_init_migratetype(struct folio *folio,
-							  struct hstate *h)
-{
-	unsigned long nr_pages = pages_per_huge_page(h), i;
-
-	WARN_ON_ONCE(!pageblock_aligned(folio_pfn(folio)));
-
-	for (i = 0; i < nr_pages; i += pageblock_nr_pages) {
-		if (!folio_test_hugetlb_cma(folio))
-			init_pageblock_migratetype(folio_page(folio, i),
-					  MIGRATE_MOVABLE, false);
-	}
-}
-
 static void __init prep_and_add_bootmem_folios(struct hstate *h,
 					struct list_head *folio_list)
 {
@@ -3253,7 +3229,6 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h,
 	struct folio *folio, *tmp_f;
 
 	list_for_each_entry_safe(folio, tmp_f, folio_list, lru) {
-		hugetlb_bootmem_init_migratetype(folio, h);
 		/* Subdivide locks to achieve better parallel performance */
 		spin_lock_irqsave(&hugetlb_lock, flags);
 		account_new_hugetlb_folio(h, folio);
diff --git a/mm/mm_init.c b/mm/mm_init.c
index 61a720bb44dc..e05db8abde2f 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -751,6 +751,9 @@ void __meminit memmap_init_compound_page_frozen(struct page *head,
 	for (unsigned long i = 1; i < nr_pages; i++)
 		memmap_init_page_from_template(head + i, pfn + i, zone, &template);
 	prep_compound_head(head, order);
+
+	pageblock_migratetype_init_range(pfn, 1UL << order, MIGRATE_MOVABLE,
+					 /* isolate */ false, /* atomic */ false);
 }
 
 struct zone __meminit *pfn_to_zone(unsigned long pfn, int nid)
@@ -1110,6 +1113,9 @@ static void memmap_init_zone_device_basepages(unsigned long start, unsigned long
 		if (IS_ALIGNED(pfn, PAGES_PER_SECTION))
 			cond_resched();
 	}
+
+	pageblock_migratetype_init_range(start, end - start, MIGRATE_MOVABLE,
+					 /* isolate */ false, /* atomic */ false);
 }
 
 void __ref memmap_init_zone_device(struct zone *zone,
@@ -1150,13 +1156,8 @@ void __ref memmap_init_zone_device(struct zone *zone,
 
 		memmap_init_compound_page_frozen(head, pfn, zone, pgmap->vmemmap_shift);
 		memmap_init_zone_device_head_page(head, pgmap);
-		if (IS_ALIGNED(pfn, PAGES_PER_SECTION))
-			cond_resched();
 	}
 out:
-	pageblock_migratetype_init_range(start_pfn, nr_pages, MIGRATE_MOVABLE,
-					 /* isolate */ false, /* atomic */ false);
-
 	pr_debug("%s initialised %lu pages in %ums\n", __func__,
 		nr_pages, jiffies_to_msecs(jiffies - start));
 }
-- 
2.54.0