[RFC PATCH 07/18] mm/thp: use ptdesc in copy_huge_pmd

From: alexs
Date: Tue Jul 30 2024 - 02:45:12 EST


From: Alex Shi <alexs@xxxxxxxxxx>

Since we have ptdesc struct now, better to use replace pgtable_t, aka
'struct page *'. It's alaos a preparation for return ptdesc pointer
in pte_alloc_one series function.

Signed-off-by: Alex Shi <alexs@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a331d4504d52..236e1582d97e 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1369,15 +1369,15 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
struct page *src_page;
struct folio *src_folio;
pmd_t pmd;
- pgtable_t pgtable = NULL;
+ struct ptdesc *ptdesc = NULL;
int ret = -ENOMEM;

/* Skip if can be re-fill on fault */
if (!vma_is_anonymous(dst_vma))
return 0;

- pgtable = pte_alloc_one(dst_mm);
- if (unlikely(!pgtable))
+ ptdesc = page_ptdesc(pte_alloc_one(dst_mm));
+ if (unlikely(!ptdesc))
goto out;

dst_ptl = pmd_lock(dst_mm, dst_pmd);
@@ -1404,7 +1404,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
}
add_mm_counter(dst_mm, MM_ANONPAGES, HPAGE_PMD_NR);
mm_inc_nr_ptes(dst_mm);
- pgtable_trans_huge_deposit(dst_mm, dst_pmd, pgtable);
+ pgtable_trans_huge_deposit(dst_mm, dst_pmd, ptdesc_page(ptdesc));
if (!userfaultfd_wp(dst_vma))
pmd = pmd_swp_clear_uffd_wp(pmd);
set_pmd_at(dst_mm, addr, dst_pmd, pmd);
@@ -1414,7 +1414,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
#endif

if (unlikely(!pmd_trans_huge(pmd))) {
- pte_free(dst_mm, pgtable);
+ pte_free(dst_mm, ptdesc_page(ptdesc));
goto out_unlock;
}
/*
@@ -1440,7 +1440,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
if (unlikely(folio_try_dup_anon_rmap_pmd(src_folio, src_page, src_vma))) {
/* Page maybe pinned: split and retry the fault on PTEs. */
folio_put(src_folio);
- pte_free(dst_mm, pgtable);
+ pte_free(dst_mm, ptdesc_page(ptdesc));
spin_unlock(src_ptl);
spin_unlock(dst_ptl);
__split_huge_pmd(src_vma, src_pmd, addr, false, NULL);
@@ -1449,7 +1449,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
add_mm_counter(dst_mm, MM_ANONPAGES, HPAGE_PMD_NR);
out_zero_page:
mm_inc_nr_ptes(dst_mm);
- pgtable_trans_huge_deposit(dst_mm, dst_pmd, pgtable);
+ pgtable_trans_huge_deposit(dst_mm, dst_pmd, ptdesc_page(ptdesc));
pmdp_set_wrprotect(src_mm, addr, src_pmd);
if (!userfaultfd_wp(dst_vma))
pmd = pmd_clear_uffd_wp(pmd);
--
2.43.0