[PATCH v2 5/6] mm/hugetlb-cgroup: convert hugetlb_cgroup_css_offline() to work on folios

David Hildenbrand
2025-01-13T13:17:00Z

Let's convert hugetlb_cgroup_css_offline() and
hugetlb_cgroup_move_parent() to work on folios. hugepage_activelist
contains folios, not pages.

While at it, rename page_hcg simply to hcg, removing most of the "page"
terminology.

This removes an unnecessary call to compound_head().

Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
mm/hugetlb_cgroup.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c
index 89a8ad45a533d..bb9578bd99f98 100644
--- a/mm/hugetlb_cgroup.c
+++ b/mm/hugetlb_cgroup.c
@@ -195,24 +195,23 @@ static void hugetlb_cgroup_css_free(struct cgroup_subsys_state *css)
* cannot fail.
*/
static void hugetlb_cgroup_move_parent(int idx, struct hugetlb_cgroup *h_cg,
- struct page *page)
+ struct folio *folio)
{
unsigned int nr_pages;
struct page_counter *counter;
- struct hugetlb_cgroup *page_hcg;
+ struct hugetlb_cgroup *hcg;
struct hugetlb_cgroup *parent = parent_hugetlb_cgroup(h_cg);
- struct folio *folio = page_folio(page);

- page_hcg = hugetlb_cgroup_from_folio(folio);
+ hcg = hugetlb_cgroup_from_folio(folio);
/*
* We can have pages in active list without any cgroup
* ie, hugepage with less than 3 pages. We can safely
* ignore those pages.
*/
- if (!page_hcg || page_hcg != h_cg)
+ if (!hcg || hcg != h_cg)
goto out;

- nr_pages = compound_nr(page);
+ nr_pages = folio_nr_pages(folio);
if (!parent) {
parent = root_h_cgroup;
/* root has no limit */
@@ -235,13 +234,13 @@ static void hugetlb_cgroup_css_offline(struct cgroup_subsys_state *css)
{
struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(css);
struct hstate *h;
- struct page *page;
+ struct folio *folio;

do {
for_each_hstate(h) {
spin_lock_irq(&hugetlb_lock);
- list_for_each_entry(page, &h->hugepage_activelist, lru)
- hugetlb_cgroup_move_parent(hstate_index(h), h_cg, page);
+ list_for_each_entry(folio, &h->hugepage_activelist, lru)
+ hugetlb_cgroup_move_parent(hstate_index(h), h_cg, folio);

spin_unlock_irq(&hugetlb_lock);
}
--
2.47.1