[PATCH v3 18/19] mm/hugetlb: Remove unused bootmem cma field

[Muchun Song]

struct huge_bootmem_page no longer needs to keep the CMA pointer. The
bootmem path only needs to remember whether a huge page came from CMA,
which is already encoded in the flags field.

Set HUGE_BOOTMEM_CMA when the page is allocated and drop the unused cma
field together with the redundant assignments.

Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
 mm/hugetlb.c     |  5 +----
 mm/hugetlb_cma.c | 29 +++++++++++------------------
 mm/internal.h    |  2 --
 3 files changed, 12 insertions(+), 24 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 47c3d6d11c58..fb7ad2a4a26b 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3076,10 +3076,7 @@ static bool __init alloc_bootmem_huge_page(struct hstate *h, int nid)
 	 */
 	INIT_LIST_HEAD(&m->list);
 	m->hstate = h;
-	if (!hugetlb_early_cma(h)) {
-		m->cma = NULL;
-		m->flags = 0;
-	}
+	m->flags = hugetlb_early_cma(h) ? HUGE_BOOTMEM_CMA : 0;
 
 	/* CMA pages: zone-crossing is validated in hugetlb_cma_reserve(). */
 	if (!hugetlb_early_cma(h) &&
diff --git a/mm/hugetlb_cma.c b/mm/hugetlb_cma.c
index e487d0ffffc0..4dfce68b354a 100644
--- a/mm/hugetlb_cma.c
+++ b/mm/hugetlb_cma.c
@@ -59,31 +59,24 @@ struct folio *hugetlb_cma_alloc_frozen_folio(int order, gfp_t gfp_mask,
 void * __init hugetlb_cma_alloc_bootmem(struct hstate *h, int nid, bool node_exact)
 {
 	struct cma *cma;
-	struct huge_bootmem_page *m;
+	void *m;
 	int node;
 
 	cma = hugetlb_cma[nid];
 	m = cma_reserve_early(cma, huge_page_size(h));
-	if (!m) {
-		if (node_exact)
-			return NULL;
+	if (m || node_exact)
+		return m;
 
-		for_each_node_mask(node, hugetlb_bootmem_nodes) {
-			cma = hugetlb_cma[node];
-			if (!cma || node == nid)
-				continue;
-			m = cma_reserve_early(cma, huge_page_size(h));
-			if (m)
-				break;
-		}
-	}
-
-	if (m) {
-		m->flags = HUGE_BOOTMEM_CMA;
-		m->cma = cma;
+	for_each_node_mask(node, hugetlb_bootmem_nodes) {
+		cma = hugetlb_cma[node];
+		if (!cma || node == nid)
+			continue;
+		m = cma_reserve_early(cma, huge_page_size(h));
+		if (m)
+			return m;
 	}
 
-	return m;
+	return NULL;
 }
 
 static int __init cmdline_parse_hugetlb_cma(char *p)
diff --git a/mm/internal.h b/mm/internal.h
index 6b9802460a7c..8497673d0ac3 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -24,13 +24,11 @@
 
 struct folio_batch;
 struct hstate;
-struct cma;
 
 struct huge_bootmem_page {
 	struct list_head list;
 	struct hstate *hstate;
 	unsigned long flags;
-	struct cma *cma;
 };
 
 /*
-- 
2.54.0