2023-07-27 22:21:15

by Yun Levi

Subject: [PATCH v2] damon: Use pmdp_get instead of drectly dereferencing pmd.

As ptep_get, Use the pmdp_get wrapper when we accessing pmdval
instead of directly dereferencing pmd.

Signed-off-by: Levi Yun <[email protected]>
---
mm/damon/ops-common.c | 2 +-
mm/damon/paddr.c | 2 +-
mm/damon/vaddr.c | 23 +++++++++++++++--------
3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c
index e940802a15a4..ac1c3fa80f98 100644
--- a/mm/damon/ops-common.c
+++ b/mm/damon/ops-common.c
@@ -54,7 +54,7 @@ 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(*pmd));
+ struct folio *folio = damon_get_folio(pmd_pfn(pmdp_get(pmd)));

if (!folio)
return;
diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 40801e38fcf0..909db25efb35 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -94,7 +94,7 @@ static bool __damon_pa_young(struct folio *folio, struct vm_area_struct *vma,
mmu_notifier_test_young(vma->vm_mm, addr);
} else {
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- *accessed = pmd_young(*pvmw.pmd) ||
+ *accessed = pmd_young(pmdp_get(pvmw.pmd)) ||
!folio_test_idle(folio) ||
mmu_notifier_test_young(vma->vm_mm, addr);
#else
diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index 2fcc9731528a..d01cc46f4bf4 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -301,16 +301,19 @@ static int damon_mkold_pmd_entry(pmd_t *pmd, unsigned long addr,
unsigned long next, struct mm_walk *walk)
{
pte_t *pte;
+ pmd_t pmde;
spinlock_t *ptl;

- if (pmd_trans_huge(*pmd)) {
+ if (pmd_trans_huge(pmdp_get(pmd))) {
ptl = pmd_lock(walk->mm, pmd);
- if (!pmd_present(*pmd)) {
+ pmde = pmdp_get(pmd);
+
+ if (!pmd_present(pmde)) {
spin_unlock(ptl);
return 0;
}

- if (pmd_trans_huge(*pmd)) {
+ if (pmd_trans_huge(pmde)) {
damon_pmdp_mkold(pmd, walk->vma, addr);
spin_unlock(ptl);
return 0;
@@ -439,21 +442,25 @@ static int damon_young_pmd_entry(pmd_t *pmd, unsigned long addr,
struct damon_young_walk_private *priv = walk->private;

#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- if (pmd_trans_huge(*pmd)) {
+ if (pmd_trans_huge(pmdp_get(pmd))) {
+ pmd_t pmde;
+
ptl = pmd_lock(walk->mm, pmd);
- if (!pmd_present(*pmd)) {
+ pmde = pmdp_get(pmd);
+
+ if (!pmd_present(pmde)) {
spin_unlock(ptl);
return 0;
}

- if (!pmd_trans_huge(*pmd)) {
+ if (!pmd_trans_huge(pmde)) {
spin_unlock(ptl);
goto regular_page;
}
- folio = damon_get_folio(pmd_pfn(*pmd));
+ folio = damon_get_folio(pmd_pfn(pmde));
if (!folio)
goto huge_out;
- if (pmd_young(*pmd) || !folio_test_idle(folio) ||
+ if (pmd_young(pmde) || !folio_test_idle(folio) ||
mmu_notifier_test_young(walk->mm,
addr))
priv->young = true;
--
2.37.2