[RFC,v2,03/47] hugetlb: remove redundant pte_mkhuge in migration path

Message ID 20221021163703.3218176-4-jthoughton@google.com
State New
Headers
Series hugetlb: introduce HugeTLB high-granularity mapping |

Commit Message

James Houghton Oct. 21, 2022, 4:36 p.m. UTC
  arch_make_huge_pte, which is called immediately following pte_mkhuge,
already makes the necessary changes to the PTE that pte_mkhuge would
have. The generic implementation of arch_make_huge_pte simply calls
pte_mkhuge.

Signed-off-by: James Houghton <jthoughton@google.com>
---
 mm/migrate.c | 1 -
 1 file changed, 1 deletion(-)
  

Comments

Peter Xu Nov. 16, 2022, 4:36 p.m. UTC | #1
On Fri, Oct 21, 2022 at 04:36:19PM +0000, James Houghton wrote:
> arch_make_huge_pte, which is called immediately following pte_mkhuge,
> already makes the necessary changes to the PTE that pte_mkhuge would
> have. The generic implementation of arch_make_huge_pte simply calls
> pte_mkhuge.
> 
> Signed-off-by: James Houghton <jthoughton@google.com>

Acked-by: Peter Xu <peterx@redhat.com>
  
Mina Almasry Dec. 7, 2022, 11:16 p.m. UTC | #2
On Fri, Oct 21, 2022 at 9:37 AM James Houghton <jthoughton@google.com> wrote:
>
> arch_make_huge_pte, which is called immediately following pte_mkhuge,
> already makes the necessary changes to the PTE that pte_mkhuge would
> have. The generic implementation of arch_make_huge_pte simply calls
> pte_mkhuge.
>
> Signed-off-by: James Houghton <jthoughton@google.com>

Acked-by: Mina Almasry <almasrymina@google.com>

> ---
>  mm/migrate.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 8e5eb6ed9da2..1457cdbb7828 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -237,7 +237,6 @@ static bool remove_migration_pte(struct folio *folio,
>                 if (folio_test_hugetlb(folio)) {
>                         unsigned int shift = huge_page_shift(hstate_vma(vma));
>
> -                       pte = pte_mkhuge(pte);
>                         pte = arch_make_huge_pte(pte, shift, vma->vm_flags);
>                         if (folio_test_anon(folio))
>                                 hugepage_add_anon_rmap(new, vma, pvmw.address,
> --
> 2.38.0.135.g90850a2211-goog
>
  
Mike Kravetz Dec. 9, 2022, 12:10 a.m. UTC | #3
On 10/21/22 16:36, James Houghton wrote:
> arch_make_huge_pte, which is called immediately following pte_mkhuge,
> already makes the necessary changes to the PTE that pte_mkhuge would
> have. The generic implementation of arch_make_huge_pte simply calls
> pte_mkhuge.
> 
> Signed-off-by: James Houghton <jthoughton@google.com>
> ---
>  mm/migrate.c | 1 -
>  1 file changed, 1 deletion(-)

Thanks,

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
  

Patch

diff --git a/mm/migrate.c b/mm/migrate.c
index 8e5eb6ed9da2..1457cdbb7828 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -237,7 +237,6 @@  static bool remove_migration_pte(struct folio *folio,
 		if (folio_test_hugetlb(folio)) {
 			unsigned int shift = huge_page_shift(hstate_vma(vma));
 
-			pte = pte_mkhuge(pte);
 			pte = arch_make_huge_pte(pte, shift, vma->vm_flags);
 			if (folio_test_anon(folio))
 				hugepage_add_anon_rmap(new, vma, pvmw.address,