mm: debug_vm_pgtable: add debug_vm_pgtable_free_huge_page()

Patch series "mm: hugetlb: allocate frozen gigantic folio", v6.

Introduce alloc_contig_frozen_pages() and cma_alloc_frozen_compound()
which avoid atomic operation about page refcount, and then convert to
allocate frozen gigantic folio by the new helpers in hugetlb to cleanup
the alloc_gigantic_folio().


This patch (of 6):

Add a new helper to free huge page to be consistency to
debug_vm_pgtable_alloc_huge_page(), and use HPAGE_PUD_ORDER instead of
open-code.

Also move the free_contig_range() under CONFIG_ALLOC_CONTIG since all
caller are built with CONFIG_ALLOC_CONTIG.

Link: https://lkml.kernel.org/r/20260109093136.1491549-2-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 17 insertions, 21 deletions

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index ae9b9310d96f..83cf07269f13 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -971,22 +971,26 @@ static unsigned long __init get_random_vaddr(void)
 	return random_vaddr;
 }
 
-static void __init destroy_args(struct pgtable_debug_args *args)
+static void __init
+debug_vm_pgtable_free_huge_page(struct pgtable_debug_args *args,
+		unsigned long pfn, int order)
 {
-	struct page *page = NULL;
+#ifdef CONFIG_CONTIG_ALLOC
+	if (args->is_contiguous_page) {
+		free_contig_range(pfn, 1 << order);
+		return;
+	}
+#endif
+	__free_pages(pfn_to_page(pfn), order);
+}
 
+static void __init destroy_args(struct pgtable_debug_args *args)
+{
 	/* Free (huge) page */
 	if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
 	    has_transparent_pud_hugepage() &&
 	    args->pud_pfn != ULONG_MAX) {
-		if (args->is_contiguous_page) {
-			free_contig_range(args->pud_pfn,
-					  (1 << (HPAGE_PUD_SHIFT - PAGE_SHIFT)));
-		} else {
-			page = pfn_to_page(args->pud_pfn);
-			__free_pages(page, HPAGE_PUD_SHIFT - PAGE_SHIFT);
-		}
-
+		debug_vm_pgtable_free_huge_page(args, args->pud_pfn, HPAGE_PUD_ORDER);
 		args->pud_pfn = ULONG_MAX;
 		args->pmd_pfn = ULONG_MAX;
 		args->pte_pfn = ULONG_MAX;
@@ -995,20 +999,13 @@ static void __init destroy_args(struct pgtable_debug_args *args)
 	if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
 	    has_transparent_hugepage() &&
 	    args->pmd_pfn != ULONG_MAX) {
-		if (args->is_contiguous_page) {
-			free_contig_range(args->pmd_pfn, (1 << HPAGE_PMD_ORDER));
-		} else {
-			page = pfn_to_page(args->pmd_pfn);
-			__free_pages(page, HPAGE_PMD_ORDER);
-		}
-
+		debug_vm_pgtable_free_huge_page(args, args->pmd_pfn, HPAGE_PMD_ORDER);
 		args->pmd_pfn = ULONG_MAX;
 		args->pte_pfn = ULONG_MAX;
 	}
 
 	if (args->pte_pfn != ULONG_MAX) {
-		page = pfn_to_page(args->pte_pfn);
-		__free_page(page);
+		__free_page(pfn_to_page(args->pte_pfn));
 
 		args->pte_pfn = ULONG_MAX;
 	}
@@ -1242,8 +1239,7 @@ static int __init init_args(struct pgtable_debug_args *args)
 	 */
 	if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
 	    has_transparent_pud_hugepage()) {
-		page = debug_vm_pgtable_alloc_huge_page(args,
-				HPAGE_PUD_SHIFT - PAGE_SHIFT);
+		page = debug_vm_pgtable_alloc_huge_page(args, HPAGE_PUD_ORDER);
 		if (page) {
 			args->pud_pfn = page_to_pfn(page);
 			args->pmd_pfn = args->pud_pfn;