On 04.07.24 06:31, Oscar Salvador wrote:
PMD-mapped hugetlb vmas will also reach damon_mkold_pmd_entry.
Add the required code so it knows how to handle those there.
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
---
mm/damon/ops-common.c | 21 ++++++++++++++++-----
mm/damon/vaddr.c | 15 +++++----------
2 files changed, 21 insertions(+), 15 deletions(-)
(besides a lot of this code needing cleanups and likely fixes)
diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c
index d25d99cb5f2b..6727658a3ef5 100644
--- a/mm/damon/ops-common.c
+++ b/mm/damon/ops-common.c
@@ -53,18 +53,29 @@ void damon_ptep_mkold(pte_t *pte, struct vm_area_struct *vma, unsigned long addr
void damon_pmdp_mkold(pmd_t *pmd, struct vm_area_struct *vma, unsigned long addr)
{
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- struct folio *folio = damon_get_folio(pmd_pfn(pmdp_get(pmd)));
+#ifdef CONFIG_PGTABLE_HAS_HUGE_LEAVES
+ struct folio *folio;
+ unsigned long size;
+
+ if (is_vm_hugetlb_page(vma)) {
+ folio = pfn_folio(pdm_pfn(*pmd))
+ folio_get(folio);
+ size = huge_page_size(hstate_vma(vma));
+ } else {
+ folio = damon_get_folio(pmd_pfn(*pmd));
+ size = PMD_SIZE;
+ }
if (!folio)
- return;
+ return 0;
- if (pmdp_clear_young_notify(vma, addr, pmd))
+ if (pmdp_test_and_clear_young(vma, addr, pmd) ||
+ mmu_notifier_clear_young(mm, addr, addr + size))
folio_set_young(folio);
And I think here is the issue for both the cont-PMD and cont-PTE case:
For hugetlb we *absolutely must* use the set_huge_pte_at()-style
functions, otherwise we might suddenly lose the cont-pte/cont-pmd bit.
We cannot arbitrarily replace these "huge_pte" functions by others that
work on individual PTEs/PMDs.
(noting that the hugetlb code in damon_hugetlb_mkold() is likely not
correct, because we could be losing concurrently set dirty bits I believe)
--
Cheers,
David / dhildenb
