Re: [PATCH 5/6] mm: change to return bool for pudp_test_and_clear_young()

["Lorenzo Stoakes (Oracle)" <ljs@kernel.org>]

On Thu, Mar 19, 2026 at 11:24:04AM +0800, Baolin Wang wrote:
> The pudp_test_and_clear_young() is used to clear the young flag,
> returning whether the young flag was set for this PUD entry. Change
> the return type to bool to make the intention clearer.
>
> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>

Some nits but otherwise loogs good so:

Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>

> ---
>  arch/powerpc/include/asm/book3s/64/pgtable.h | 10 +++++-----
>  arch/powerpc/mm/book3s64/pgtable.c           |  4 ++--
>  arch/riscv/include/asm/pgtable.h             |  4 ++--
>  arch/x86/include/asm/pgtable.h               |  4 ++--
>  arch/x86/mm/pgtable.c                        |  6 +++---
>  5 files changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
> index 0f34011665a6..083c4b9ed5b3 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
> @@ -1172,13 +1172,13 @@ static inline bool __pmdp_test_and_clear_young(struct mm_struct *mm,
>  	return ((old & _PAGE_ACCESSED) != 0);
>  }
>
> -static inline int __pudp_test_and_clear_young(struct mm_struct *mm,
> -					      unsigned long addr, pud_t *pudp)
> +static inline bool __pudp_test_and_clear_young(struct mm_struct *mm,
> +					       unsigned long addr, pud_t *pudp)

Formatting yada yada you know the drill, 2 tabs etc. :))

>  {
>  	unsigned long old;
>
>  	if ((pud_raw(*pudp) & cpu_to_be64(_PAGE_ACCESSED | H_PAGE_HASHPTE)) == 0)
> -		return 0;
> +		return false;
>  	old = pud_hugepage_update(mm, addr, pudp, _PAGE_ACCESSED, 0);
>  	return ((old & _PAGE_ACCESSED) != 0);
>  }
> @@ -1303,8 +1303,8 @@ extern int pudp_set_access_flags(struct vm_area_struct *vma,
>  extern bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
>  				      unsigned long address, pmd_t *pmdp);
>  #define __HAVE_ARCH_PUDP_TEST_AND_CLEAR_YOUNG
> -extern int pudp_test_and_clear_young(struct vm_area_struct *vma,
> -				     unsigned long address, pud_t *pudp);
> +extern bool pudp_test_and_clear_young(struct vm_area_struct *vma,
> +				      unsigned long address, pud_t *pudp);

Drop the extern please!

>
>
>  #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
> diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
> index aed39bba891e..838cb4a8e2cf 100644
> --- a/arch/powerpc/mm/book3s64/pgtable.c
> +++ b/arch/powerpc/mm/book3s64/pgtable.c
> @@ -104,8 +104,8 @@ bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
>  	return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp);
>  }
>
> -int pudp_test_and_clear_young(struct vm_area_struct *vma,
> -			      unsigned long address, pud_t *pudp)
> +bool pudp_test_and_clear_young(struct vm_area_struct *vma,
> +			       unsigned long address, pud_t *pudp)
>  {
>  	return __pudp_test_and_clear_young(vma->vm_mm, address, pudp);
>  }
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index bac559d29036..88fa63186ca5 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -1109,8 +1109,8 @@ static inline int pudp_set_access_flags(struct vm_area_struct *vma,
>  	return ptep_set_access_flags(vma, address, (pte_t *)pudp, pud_pte(entry), dirty);
>  }
>
> -static inline int pudp_test_and_clear_young(struct vm_area_struct *vma,
> -					    unsigned long address, pud_t *pudp)
> +static inline bool pudp_test_and_clear_young(struct vm_area_struct *vma,
> +					     unsigned long address, pud_t *pudp)
>  {
>  	return ptep_test_and_clear_young(vma, address, (pte_t *)pudp);
>  }
> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> index f9439449c9bd..6ca1fdd25191 100644
> --- a/arch/x86/include/asm/pgtable.h
> +++ b/arch/x86/include/asm/pgtable.h
> @@ -1297,8 +1297,8 @@ extern int pudp_set_access_flags(struct vm_area_struct *vma,
>  #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
>  extern bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
>  				      unsigned long addr, pmd_t *pmdp);
> -extern int pudp_test_and_clear_young(struct vm_area_struct *vma,
> -				     unsigned long addr, pud_t *pudp);
> +extern bool pudp_test_and_clear_young(struct vm_area_struct *vma,
> +				      unsigned long addr, pud_t *pudp);

Drop the extern please!

>
>  #define __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
>  extern bool pmdp_clear_flush_young(struct vm_area_struct *vma,
> diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
> index 8c336edf0e65..2677dcf0bbce 100644
> --- a/arch/x86/mm/pgtable.c
> +++ b/arch/x86/mm/pgtable.c
> @@ -470,10 +470,10 @@ bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
>  #endif
>
>  #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> -int pudp_test_and_clear_young(struct vm_area_struct *vma,
> -			      unsigned long addr, pud_t *pudp)
> +bool pudp_test_and_clear_young(struct vm_area_struct *vma,
> +			       unsigned long addr, pud_t *pudp)
>  {
> -	int ret = 0;
> +	bool ret = false;
>
>  	if (pud_young(*pudp))
>  		ret = test_and_clear_bit(_PAGE_BIT_ACCESSED,
> --
> 2.47.3
>