diff mbox series

[v2,66/69] mm/cma: Move CMA pageblock initialization into cma_activate_area()

Message ID 20260513132044.41690-20-songmuchun@bytedance.com (mailing list archive)
State Handled Elsewhere
Headers show
Series mm: Generalize HVO for HugeTLB and device DAX | expand

Commit Message

Muchun Song May 13, 2026, 1:20 p.m. UTC 
Move CMA pageblock initialization for early-reserved pages into
cma_activate_area() so CMA pageblock setup is handled in one place.

This keeps init_cma_pageblock() in the CMA core instead of pushing
special handling for early CMA allocations into its callers.

As a side effect, this also fixes the zone->cma_pages accounting race for
early-reserved HugeTLB CMA pages. The accounting is no longer updated from
parallel hugetlb_struct_page_init() workers and is instead performed
serially from cma_activate_area().

Fixes: d2d786714080 ("mm/hugetlb: enable bootmem allocation from CMA areas")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
 mm/cma.c     | 7 +++++--
 mm/hugetlb.c | 8 +++-----
 2 files changed, 8 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/mm/cma.c b/mm/cma.c
index 0369f04c7ba5..c1896c0db63d 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -162,6 +162,10 @@  static void __init cma_activate_area(struct cma *cma)
 			count = early_pfn[r] - cmr->base_pfn;
 			bitmap_count = cma_bitmap_pages_to_bits(cma, count);
 			bitmap_set(cmr->bitmap, 0, bitmap_count);
+
+			for (pfn = cmr->base_pfn; pfn < early_pfn[r];
+			     pfn += pageblock_nr_pages)
+				init_cma_pageblock(pfn_to_page(pfn));
 		}
 
 		WARN_ON_ONCE(!pfn_valid(cmr->base_pfn));
@@ -1098,8 +1102,7 @@  bool cma_intersects(struct cma *cma, unsigned long start, unsigned long end)
  *
  * The caller is responsible for initializing the page structures
  * in the area properly, since this just points to memblock-allocated
- * memory. The caller should subsequently use init_cma_pageblock to
- * set the migrate type and CMA stats  the pageblocks that were reserved.
+ * memory.
  *
  * If the CMA area fails to activate later, memory obtained through
  * this interface is not handed to the page allocator, this is
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7e9f49882395..df798f9386d6 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3136,9 +3136,7 @@  static void __init hugetlb_bootmem_init_migratetype(struct folio *folio,
 	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_cma_pageblock(folio_page(folio, i));
-		else
+		if (!folio_test_hugetlb_cma(folio))
 			init_pageblock_migratetype(folio_page(folio, i),
 					  MIGRATE_MOVABLE, false);
 	}
@@ -3206,8 +3204,8 @@  static void __init gather_bootmem_prealloc_node(unsigned long nid)
 		 * in order to fix confusing memory reports from free(1) and
 		 * other side-effects, like CommitLimit going negative.
 		 *
-		 * For CMA pages, this is done in init_cma_pageblock
-		 * (via hugetlb_bootmem_init_migratetype), so skip it here.
+		 * For CMA pages, this is done in cma_activate_area(), so skip
+		 * it here.
 		 */
 		if (!folio_test_hugetlb_cma(folio))
 			adjust_managed_page_count(page, nr_pages);