[PATCH mm-unstable 8/8] mm/hugetlb: convert demote_free_huge_page to folios

From: Sidhartha Kumar <sidhartha.kumar@oracle.com>
To: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc: akpm@linux-foundation.org, songmuchun@bytedance.com,
	mike.kravetz@oracle.com, willy@infradead.org,
	tsahu@linux.ibm.com, jhubbard@nvidia.com,
	Sidhartha Kumar <sidhartha.kumar@oracle.com>
Subject: [PATCH mm-unstable 8/8] mm/hugetlb: convert demote_free_huge_page to folios
Date: Tue,  3 Jan 2023 13:13:40 -0600	[thread overview]
Message-ID: <20230103191340.116536-9-sidhartha.kumar@oracle.com> (raw)
In-Reply-To: <20230103191340.116536-1-sidhartha.kumar@oracle.com>

Change demote_free_huge_page to demote_free_hugetlb_folio() and change
demote_pool_huge_page() pass in a folio.

Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
---
 mm/hugetlb.c | 31 ++++++++++++++++---------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 2bb69b098117..a89728c6987d 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3438,12 +3438,12 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
 	return 0;
 }
 
-static int demote_free_huge_page(struct hstate *h, struct page *page)
+static int demote_free_hugetlb_folio(struct hstate *h, struct folio *folio)
 {
-	int i, nid = page_to_nid(page);
+	int i, nid = folio_nid(folio);
 	struct hstate *target_hstate;
-	struct folio *folio = page_folio(page);
 	struct page *subpage;
+	struct folio *subfolio;
 	int rc = 0;
 
 	target_hstate = size_to_hstate(PAGE_SIZE << h->demote_order);
@@ -3451,18 +3451,18 @@ static int demote_free_huge_page(struct hstate *h, struct page *page)
 	remove_hugetlb_folio_for_demote(h, folio, false);
 	spin_unlock_irq(&hugetlb_lock);
 
-	rc = hugetlb_vmemmap_restore(h, page);
+	rc = hugetlb_vmemmap_restore(h, &folio->page);
 	if (rc) {
-		/* Allocation of vmemmmap failed, we can not demote page */
+		/* Allocation of vmemmmap failed, we can not demote folio */
 		spin_lock_irq(&hugetlb_lock);
-		set_page_refcounted(page);
-		add_hugetlb_folio(h, page_folio(page), false);
+		folio_ref_unfreeze(folio, 1);
+		add_hugetlb_folio(h, folio, false);
 		return rc;
 	}
 
 	/*
 	 * Use destroy_compound_hugetlb_folio_for_demote for all huge page
-	 * sizes as it will not ref count pages.
+	 * sizes as it will not ref count folios.
 	 */
 	destroy_compound_hugetlb_folio_for_demote(folio, huge_page_order(h));
 
@@ -3477,15 +3477,15 @@ static int demote_free_huge_page(struct hstate *h, struct page *page)
 	mutex_lock(&target_hstate->resize_lock);
 	for (i = 0; i < pages_per_huge_page(h);
 				i += pages_per_huge_page(target_hstate)) {
-		subpage = nth_page(page, i);
-		folio = page_folio(subpage);
+		subpage = folio_page(folio, i);
+		subfolio = page_folio(subpage);
 		if (hstate_is_gigantic(target_hstate))
-			prep_compound_gigantic_folio_for_demote(folio,
+			prep_compound_gigantic_folio_for_demote(subfolio,
 							target_hstate->order);
 		else
 			prep_compound_page(subpage, target_hstate->order);
-		set_page_private(subpage, 0);
-		prep_new_hugetlb_folio(target_hstate, folio, nid);
+		folio_change_private(subfolio, NULL);
+		prep_new_hugetlb_folio(target_hstate, subfolio, nid);
 		free_huge_page(subpage);
 	}
 	mutex_unlock(&target_hstate->resize_lock);
@@ -3508,6 +3508,7 @@ static int demote_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed)
 {
 	int nr_nodes, node;
 	struct page *page;
+	struct folio *folio;
 
 	lockdep_assert_held(&hugetlb_lock);
 
@@ -3521,8 +3522,8 @@ static int demote_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed)
 		list_for_each_entry(page, &h->hugepage_freelists[node], lru) {
 			if (PageHWPoison(page))
 				continue;
-
-			return demote_free_huge_page(h, page);
+			folio = page_folio(page);
+			return demote_free_hugetlb_folio(h, folio);
 		}
 	}
 
-- 
2.39.0

