[RFC PATCH 5/5] mm/damon/vaddr: support pgidle_unset probe filter type

[SJ Park <sj@kernel.org>]

DAMON virtual address space operation set (vaddr) does not support
pgidle_unset probe filter type.  Add the support.

Signed-off-by: SJ Park <sj@kernel.org>
---
 mm/damon/vaddr.c | 55 ++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 48 insertions(+), 7 deletions(-)

diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index 45239f05e113b..9a38dc89a156e 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -522,13 +522,49 @@ static void damon_va_prep_probes(struct damon_ctx *ctx, bool set_samples)
 	}
 }
 
-static bool damon_va_filter_pass(struct folio *folio, struct damon_probe *p)
+static bool damon_va_young_addr(struct folio *folio, pte_t *pte, pmd_t *pmd,
+		struct mm_struct *mm, unsigned long addr)
+{
+	bool young = false;
+
+	if (pte)
+		young = pte_young(*pte);
+	else if (pmd)
+		young = pmd_young(*pmd);
+	young = young || !folio_test_idle(folio) ||
+		mmu_notifier_test_young(mm, addr);
+	return young;
+}
+
+static bool damon_va_filter_match(struct damon_filter *filter,
+		struct folio *folio, pte_t *pte, pmd_t *pmd,
+		struct mm_struct *mm, unsigned long addr)
+{
+	bool matched = false;
+
+	switch (filter->type) {
+	case DAMON_FILTER_TYPE_PGIDLE_UNSET:
+		if (!folio)
+			matched = false;
+		else
+			matched = damon_va_young_addr(folio, pte, pmd, mm,
+					addr);
+		break;
+	default:
+		return damon_ops_filter_match(filter, folio);
+	}
+	return matched == filter->matching;
+}
+
+static bool damon_va_filter_pass(struct folio *folio, struct damon_probe *p,
+		pte_t *pte, pmd_t *pmd, struct mm_struct *mm,
+		unsigned long addr)
 {
 	struct damon_filter *f;
 	bool pass = true;
 
 	damon_for_each_filter(f, p) {
-		if (damon_ops_filter_match(f, folio)) {
+		if (damon_va_filter_match(f, folio, pte, pmd, mm, addr)) {
 			pass = f->allow;
 			break;
 		}
@@ -543,13 +579,15 @@ struct damon_va_probe_walk_private {
 };
 
 static void damon_va_probe_folio(struct damon_ctx *ctx,
-		struct damon_region *r, struct folio *folio)
+		struct damon_region *r, struct folio *folio,
+		pte_t *pte, pmd_t *pmd, struct mm_struct *mm)
 {
 	struct damon_probe *probe;
 	int i = 0;
 
 	damon_for_each_probe(probe, ctx) {
-		if (damon_va_filter_pass(folio, probe))
+		if (damon_va_filter_pass(folio, probe, pte, pmd, mm,
+					r->sampling_addr))
 			r->probe_hits[i]++;
 		i++;
 	}
@@ -574,7 +612,8 @@ static int damon_va_probe_pmd_entry(pmd_t *pmd, unsigned long addr,
 		folio = vm_normal_folio_pmd(walk->vma, addr, pmde);
 		if (!folio)
 			goto huge_out;
-		damon_va_probe_folio(priv->ctx, priv->r, folio);
+		damon_va_probe_folio(priv->ctx, priv->r, folio, NULL, &pmde,
+				walk->vma->vm_mm);
 
 huge_out:
 		spin_unlock(ptl);
@@ -591,7 +630,8 @@ static int damon_va_probe_pmd_entry(pmd_t *pmd, unsigned long addr,
 	folio = vm_normal_folio(walk->vma, addr, ptent);
 	if (!folio)
 		goto out;
-	damon_va_probe_folio(priv->ctx, priv->r, folio);
+	damon_va_probe_folio(priv->ctx, priv->r, folio, &ptent, NULL,
+			walk->vma->vm_mm);
 
 out:
 	pte_unmap_unlock(pte, ptl);
@@ -615,7 +655,8 @@ static int damon_va_probe_hugetlb_entry(pte_t *pte, unsigned long hmask,
 
 	folio = pfn_folio(pte_pfn(entry));
 	folio_get(folio);
-	damon_va_probe_folio(priv->ctx, priv->r, folio);
+	damon_va_probe_folio(priv->ctx, priv->r, folio, &entry, NULL,
+			walk->vma->vm_mm);
 	folio_put(folio);
 
 out:
-- 
2.47.3