2022-12-07 03:43:56

by Kefeng Wang

Subject: [PATCH 1/2] mm: huge_memory: Convert madvise_free_huge_pmd to use a folio

Using folios instead of pages removes several calls to compound_head(),

Signed-off-by: Kefeng Wang <[email protected]>
---
mm/huge_memory.c | 28 ++++++++++++++--------------
1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index abe6cfd92ffa..6e76c770529b 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1603,7 +1603,7 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
{
spinlock_t *ptl;
pmd_t orig_pmd;
- struct page *page;
+ struct folio *folio;
struct mm_struct *mm = tlb->mm;
bool ret = false;

@@ -1623,15 +1623,15 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
goto out;
}

- page = pmd_page(orig_pmd);
+ folio = pfn_folio(pmd_pfn(orig_pmd));
/*
- * If other processes are mapping this page, we couldn't discard
- * the page unless they all do MADV_FREE so let's skip the page.
+ * If other processes are mapping this folio, we couldn't discard
+ * the folio unless they all do MADV_FREE so let's skip the folio.
*/
- if (total_mapcount(page) != 1)
+ if (folio_mapcount(folio) != 1)
goto out;

- if (!trylock_page(page))
+ if (!folio_trylock(folio))
goto out;

/*
@@ -1639,17 +1639,17 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
* will deactivate only them.
*/
if (next - addr != HPAGE_PMD_SIZE) {
- get_page(page);
+ folio_get(folio);
spin_unlock(ptl);
- split_huge_page(page);
- unlock_page(page);
- put_page(page);
+ split_folio(folio);
+ folio_unlock(folio);
+ folio_put(folio);
goto out_unlocked;
}

- if (PageDirty(page))
- ClearPageDirty(page);
- unlock_page(page);
+ if (folio_test_dirty(folio))
+ folio_clear_dirty(folio);
+ folio_unlock(folio);

if (pmd_young(orig_pmd) || pmd_dirty(orig_pmd)) {
pmdp_invalidate(vma, addr, pmd);
@@ -1660,7 +1660,7 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
}

- mark_page_lazyfree(page);
+ mark_page_lazyfree(&folio->page);
ret = true;
out:
spin_unlock(ptl);
--
2.35.3

2022-12-12 20:43:25

by Vishal Moola

Subject: Re: [PATCH 1/2] mm: huge_memory: Convert madvise_free_huge_pmd to use a folio

On Wed, Dec 07, 2022 at 10:34:30AM +0800, Kefeng Wang wrote:
> Using folios instead of pages removes several calls to compound_head(),
>
> Signed-off-by: Kefeng Wang <[email protected]>

Reviewed-by: Vishal Moola (Oracle) <[email protected]>