[PATCH] mm/compaction: Use folio in hugetlb pathway

Vishal Moola (Oracle)
2025-04-01T02:11:34Z

Use a folio in the hugetlb pathway during the compaction migrate-able
pageblock scan.

This removes a call to compound_head().

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
---
include/linux/hugetlb.h | 4 ++--
mm/compaction.c | 8 ++++----
mm/hugetlb.c | 3 +--
3 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 8f3ac832ee7f..a57bed83c657 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -695,7 +695,7 @@ struct huge_bootmem_page {

bool hugetlb_bootmem_page_zones_valid(int nid, struct huge_bootmem_page *m);

-int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list);
+int isolate_or_dissolve_huge_folio(struct folio *folio, struct list_head *list);
int replace_free_hugepage_folios(unsigned long start_pfn, unsigned long end_pfn);
void wait_for_freed_hugetlb_folios(void);
struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma,
@@ -1083,7 +1083,7 @@ static inline struct folio *filemap_lock_hugetlb_folio(struct hstate *h,
return NULL;
}

-static inline int isolate_or_dissolve_huge_page(struct page *page,
+static inline int isolate_or_dissolve_huge_folio(struct folio *folio,
struct list_head *list)
{
return -ENOMEM;
diff --git a/mm/compaction.c b/mm/compaction.c
index ca71fd3c3181..dd868c861774 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1001,10 +1001,11 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
locked = NULL;
}

- ret = isolate_or_dissolve_huge_page(page, &cc->migratepages);
+ folio = page_folio(page);
+ ret = isolate_or_dissolve_huge_folio(folio, &cc->migratepages);

/*
- * Fail isolation in case isolate_or_dissolve_huge_page()
+ * Fail isolation in case isolate_or_dissolve_huge_folio()
* reports an error. In case of -ENOMEM, abort right away.
*/
if (ret < 0) {
@@ -1016,12 +1017,11 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
goto isolate_fail;
}

- if (PageHuge(page)) {
+ if (folio_test_hugetlb(folio)) {
/*
* Hugepage was successfully isolated and placed
* on the cc->migratepages list.
*/
- folio = page_folio(page);
low_pfn += folio_nr_pages(folio) - 1;
goto isolate_success_no_list;
}
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 39f92aad7bd1..93bc8c4c904b 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2896,10 +2896,9 @@ static int alloc_and_dissolve_hugetlb_folio(struct hstate *h,
return ret;
}

-int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list)
+int isolate_or_dissolve_huge_folio(struct folio *folio, struct list_head *list)
{
struct hstate *h;
- struct folio *folio = page_folio(page);
int ret = -EBUSY;

/*
--
2.48.1