+ mm-damon-use-damon_get_monitor_folio-for-hugetlb-entries.patch added to mm-unstable branch

+ mm-damon-use-damon_get_monitor_folio-for-hugetlb-entries.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/damon: use damon_get_monitor_folio() for hugetlb entries
has been added to the -mm mm-unstable branch.  Its filename is
     mm-damon-use-damon_get_monitor_folio-for-hugetlb-entries.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-use-damon_get_monitor_folio-for-hugetlb-entries.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: Gregory Price <gourry@gourry.net>
Subject: mm/damon: use damon_get_monitor_folio() for hugetlb entries
Date: Mon,  5 Oct 2026 23:52:06 -0700

Hugetlb folio acquisition is open-coded in three places:
  - damon_hugetlb_mkold()
  - damon_young_hugetlb_entry()
  - damon_va_probe_hugetlb_entry()

DAMON already has damon_get_monitor_folio(), which paddr uses to get
monitored LRU and hugetlb folios and to filter them through
damon_folio_acceptable().  These paths bypass that check.

Use that helper in these paths too, so that DAMON acquires hugetlb folios
and applies its acceptance policy in one place.

No functional change intended.  All callers reach these paths with a
present hugetlb PTE under the page table lock, so the folio is always a
mapped hugetlb folio and the helper always returns it.

Link: https://lore.kernel.org/20261006065209.41507-3-sj@kernel.org
Signed-off-by: Gregory Price (Meta) <gourry@gourry.net>
Signed-off-by: SJ Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: SJ Park <sj@kernel.org>
---

 mm/damon/ops-common.c |    6 ++++--
 mm/damon/vaddr.c      |   10 ++++++----
 2 files changed, 10 insertions(+), 6 deletions(-)

--- a/mm/damon/ops-common.c~mm-damon-use-damon_get_monitor_folio-for-hugetlb-entries
+++ a/mm/damon/ops-common.c
@@ -140,9 +140,11 @@ void damon_hugetlb_mkold(pte_t *pte, str
 {
 	bool referenced = false;
 	pte_t entry = huge_ptep_get(mm, addr, pte);
-	struct folio *folio = pfn_folio(pte_pfn(entry));
+	struct folio *folio;
 
-	folio_get(folio);
+	folio = damon_get_monitor_folio(pte_pfn(entry));
+	if (!folio)
+		return;
 
 	referenced = damon_hugetlb_ptep_mkold(pte, mm, vma, addr, &entry);
 	if (mmu_notifier_clear_young(mm, addr,
--- a/mm/damon/vaddr.c~mm-damon-use-damon_get_monitor_folio-for-hugetlb-entries
+++ a/mm/damon/vaddr.c
@@ -411,8 +411,9 @@ static int damon_young_hugetlb_entry(pte
 	if (!pte_present(entry))
 		goto out;
 
-	folio = pfn_folio(pte_pfn(entry));
-	folio_get(folio);
+	folio = damon_get_monitor_folio(pte_pfn(entry));
+	if (!folio)
+		goto out;
 
 	if (pte_young(entry) || !folio_test_idle(folio) ||
 	    mmu_notifier_test_young(walk->mm, addr))
@@ -660,8 +661,9 @@ static int damon_va_probe_hugetlb_entry(
 	if (!pte_present(entry))
 		goto out;
 
-	folio = pfn_folio(pte_pfn(entry));
-	folio_get(folio);
+	folio = damon_get_monitor_folio(pte_pfn(entry));
+	if (!folio)
+		goto out;
 	damon_va_probe_folio(priv->ctx, priv->r, folio, &entry, NULL,
 			walk->vma->vm_mm);
 	folio_put(folio);
_

Patches currently in -mm which might be from gourry@gourry.net are

mm-memory_hotplug-factor-out-node_is_memoryless.patch
mm-mempolicy-use-vm_normal_folio_pmd-in-queue_folios_pmd.patch
mm-madvise-use-vm_normal_folio_pmd-in-cold-pageout-pmd-range.patch
mm-refactor-find_next_best_node-to-find_next_best_node_in.patch
mm-page_alloc-refactor-build_node_zonelist-out-of-build_zonelists.patch
proc-task_mmu-handle-special-pmds-in-clear_refs-and-pagemap.patch
mm-madvise-reclaim-isolated-folios-if-pte-restart-fails.patch
mm-madvise-use-folio_trylock-in-the-cold-pageout-pmd-split.patch
mm-damon-use-damon_get_monitor_folio-for-hugetlb-entries.patch