[PATCH v3 06/10] mm: use pfn_swap_entry_to_folio() in zap_huge_pmd()

Matthew Wilcox (Oracle)
2024-01-11T15:24:52Z

From: Kefeng Wang <wangkefeng.wang@huawei.com>

Call pfn_swap_entry_to_folio() in zap_huge_pmd() as preparation for
converting mm counter functions to take a folio. Saves a call to
compound_head() embedded inside PageAnon().

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
mm/huge_memory.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 4ad1416b60e3..4a17306c7dda 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1895,12 +1895,14 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
zap_deposited_table(tlb->mm, pmd);
spin_unlock(ptl);
} else {
- struct page *page = NULL;
+ struct folio *folio = NULL;
int flush_needed = 1;

if (pmd_present(orig_pmd)) {
- page = pmd_page(orig_pmd);
- folio_remove_rmap_pmd(page_folio(page), page, vma);
+ struct page *page = pmd_page(orig_pmd);
+
+ folio = page_folio(page);
+ folio_remove_rmap_pmd(folio, page, vma);
VM_BUG_ON_PAGE(page_mapcount(page) < 0, page);
VM_BUG_ON_PAGE(!PageHead(page), page);
} else if (thp_migration_supported()) {
@@ -1908,23 +1910,24 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,

VM_BUG_ON(!is_pmd_migration_entry(orig_pmd));
entry = pmd_to_swp_entry(orig_pmd);
- page = pfn_swap_entry_to_page(entry);
+ folio = pfn_swap_entry_folio(entry);
flush_needed = 0;
} else
WARN_ONCE(1, "Non present huge pmd without pmd migration enabled!");

- if (PageAnon(page)) {
+ if (folio_test_anon(folio)) {
zap_deposited_table(tlb->mm, pmd);
add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
} else {
if (arch_needs_pgtable_deposit())
zap_deposited_table(tlb->mm, pmd);
- add_mm_counter(tlb->mm, mm_counter_file(page), -HPAGE_PMD_NR);
+ add_mm_counter(tlb->mm, mm_counter_file(&folio->page),
+ -HPAGE_PMD_NR);
}

spin_unlock(ptl);
if (flush_needed)
- tlb_remove_page_size(tlb, page, HPAGE_PMD_SIZE);
+ tlb_remove_page_size(tlb, &folio->page, HPAGE_PMD_SIZE);
}
return 1;
}
--
2.43.0