+ mm-hugetlb-convert-isolate_or_dissolve_huge_page-to-folios.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/hugetlb: convert isolate_or_dissolve_huge_page to folios
has been added to the -mm mm-unstable branch.  Its filename is
     mm-hugetlb-convert-isolate_or_dissolve_huge_page-to-folios.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hugetlb-convert-isolate_or_dissolve_huge_page-to-folios.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Subject: mm/hugetlb: convert isolate_or_dissolve_huge_page to folios
Date: Thu, 13 Oct 2022 20:12:59 -0700

Removes a call to compound_head() by using a folio when operating on the
head page of a hugetlb compound page.

Link: https://lkml.kernel.org/r/20221014031303.231740-6-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb.c |   13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

--- a/mm/hugetlb.c~mm-hugetlb-convert-isolate_or_dissolve_huge_page-to-folios
+++ a/mm/hugetlb.c
@@ -2822,7 +2822,7 @@ free_new:
 int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list)
 {
 	struct hstate *h;
-	struct page *head;
+	struct folio *folio = page_folio(page);
 	int ret = -EBUSY;
 
 	/*
@@ -2831,9 +2831,8 @@ int isolate_or_dissolve_huge_page(struct
 	 * Return success when racing as if we dissolved the page ourselves.
 	 */
 	spin_lock_irq(&hugetlb_lock);
-	if (PageHuge(page)) {
-		head = compound_head(page);
-		h = page_hstate(head);
+	if (folio_test_hugetlb(folio)) {
+		h = folio_hstate(folio);
 	} else {
 		spin_unlock_irq(&hugetlb_lock);
 		return 0;
@@ -2848,10 +2847,10 @@ int isolate_or_dissolve_huge_page(struct
 	if (hstate_is_gigantic(h))
 		return -ENOMEM;
 
-	if (page_count(head) && !isolate_hugetlb(head, list))
+	if (folio_ref_count(folio) && !isolate_hugetlb(&folio->page, list))
 		ret = 0;
-	else if (!page_count(head))
-		ret = alloc_and_dissolve_huge_page(h, head, list);
+	else if (!folio_ref_count(folio))
+		ret = alloc_and_dissolve_huge_page(h, &folio->page, list);
 
 	return ret;
 }
_

Patches currently in -mm which might be from sidhartha.kumar@oracle.com are

mm-hugetlb_cgroup-convert-__set_hugetlb_cgroup-to-folios.patch
mm-hugetlb_cgroup-convert-hugetlb_cgroup_from_page-to-folios.patch
mm-hugetlb_cgroup-convert-set_hugetlb_cgroup-to-folios.patch
mm-hugetlb_cgroup-convert-hugetlb_cgroup_migrate-to-folios.patch
mm-hugetlb-convert-isolate_or_dissolve_huge_page-to-folios.patch
mm-hugetlb-convert-free_huge_page-to-folios.patch
mm-hugetlb_cgroup-convert-hugetlb_cgroup_uncharge_page-to-folios.patch
mm-hugeltb_cgroup-convert-hugetlb_cgroup_commit_charge-to-folios.patch
mm-hugetlb-convert-move_hugetlb_state-to-folios.patch