linux-kernel - [PATCH v3 3/4] mm/damon/ops-common: Refactor to use {pte|pmd}p_clear_young

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Date:   Fri,  2 Jun 2023 10:29:48 +0100
From:   Ryan Roberts <ryan.roberts@....com>
To:     Andrew Morton <akpm@...ux-foundation.org>,
        SeongJae Park <sj@...nel.org>,
        Christoph Hellwig <hch@...radead.org>
Cc:     Ryan Roberts <ryan.roberts@....com>,
        "Matthew Wilcox (Oracle)" <willy@...radead.org>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Lorenzo Stoakes <lstoakes@...il.com>,
        Uladzislau Rezki <urezki@...il.com>, Zi Yan <ziy@...dia.com>,
        Yu Zhao <yuzhao@...gle.com>, Mike Rapoport <rppt@...nel.org>,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        damon@...ts.linux.dev
Subject: [PATCH v3 3/4] mm/damon/ops-common: Refactor to use {pte|pmd}p_clear_young_notify()

With the fix in place to atomically test and clear young on ptes and
pmds, simplify the code to handle the clearing for both the primary mmu
and the mmu notifier with a single API call.

Signed-off-by: Ryan Roberts <ryan.roberts@....com>
---
 mm/damon/ops-common.c | 22 ++--------------------
 1 file changed, 2 insertions(+), 20 deletions(-)

diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c
index acc264b97903..d4ab81229136 100644
--- a/mm/damon/ops-common.c
+++ b/mm/damon/ops-common.c
@@ -39,21 +39,12 @@ struct folio *damon_get_folio(unsigned long pfn)
 
 void damon_ptep_mkold(pte_t *pte, struct vm_area_struct *vma, unsigned long addr)
 {
-	bool referenced = false;
 	struct folio *folio = damon_get_folio(pte_pfn(*pte));
 
 	if (!folio)
 		return;
 
-	if (ptep_test_and_clear_young(vma, addr, pte))
-		referenced = true;
-
-#ifdef CONFIG_MMU_NOTIFIER
-	if (mmu_notifier_clear_young(vma->vm_mm, addr, addr + PAGE_SIZE))
-		referenced = true;
-#endif /* CONFIG_MMU_NOTIFIER */
-
-	if (referenced)
+	if (ptep_clear_young_notify(vma, addr, pte))
 		folio_set_young(folio);
 
 	folio_set_idle(folio);
@@ -63,21 +54,12 @@ 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
-	bool referenced = false;
 	struct folio *folio = damon_get_folio(pmd_pfn(*pmd));
 
 	if (!folio)
 		return;
 
-	if (pmdp_test_and_clear_young(vma, addr, pmd))
-		referenced = true;
-
-#ifdef CONFIG_MMU_NOTIFIER
-	if (mmu_notifier_clear_young(vma->vm_mm, addr, addr + HPAGE_PMD_SIZE))
-		referenced = true;
-#endif /* CONFIG_MMU_NOTIFIER */
-
-	if (referenced)
+	if (pmdp_clear_young_notify(vma, addr, pmd))
 		folio_set_young(folio);
 
 	folio_set_idle(folio);
-- 
2.25.1