[PATCH v2 05/10] mm: memory: use a folio in copy_nonpresent_pte()

Kefeng Wang
2023-11-04T03:56:02Z

Use a folio in copy_nonpresent_pte() to save one compound_head() call.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
mm/memory.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index 1f18ed4a5497..d9314dee355e 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -779,7 +779,7 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
unsigned long vm_flags = dst_vma->vm_flags;
pte_t orig_pte = ptep_get(src_pte);
pte_t pte = orig_pte;
- struct page *page;
+ struct folio *folio;
swp_entry_t entry = pte_to_swp_entry(orig_pte);

if (likely(!non_swap_entry(entry))) {
@@ -801,9 +801,9 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
}
rss[MM_SWAPENTS]++;
} else if (is_migration_entry(entry)) {
- page = pfn_swap_entry_to_page(entry);
+ folio = pfn_swap_entry_to_folio(entry);

- rss[mm_counter(page)]++;
+ rss[mm_counter(&folio->page)]++;

if (!is_readable_migration_entry(entry) &&
is_cow_mapping(vm_flags)) {
@@ -822,7 +822,7 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
set_pte_at(src_mm, addr, src_pte, pte);
}
} else if (is_device_private_entry(entry)) {
- page = pfn_swap_entry_to_page(entry);
+ folio = pfn_swap_entry_to_folio(entry);

/*
* Update rss count even for unaddressable pages, as
@@ -833,10 +833,10 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
* for unaddressable pages, at some point. But for now
* keep things as they are.
*/
- get_page(page);
- rss[mm_counter(page)]++;
+ folio_get(folio);
+ rss[mm_counter(&folio->page)]++;
/* Cannot fail as these pages cannot get pinned. */
- BUG_ON(page_try_dup_anon_rmap(page, false, src_vma));
+ BUG_ON(page_try_dup_anon_rmap(&folio->page, false, src_vma));

/*
* We do not preserve soft-dirty information, because so
--
2.27.0