[PATCH 1/6] mm: change to return bool for ptep_test_and_clear_young()
Baolin Wang
baolin.wang at linux.alibaba.com
Fri Mar 20 13:59:45 AEDT 2026
On 3/19/26 7:28 PM, Lorenzo Stoakes (Oracle) wrote:
> On Thu, Mar 19, 2026 at 11:24:00AM +0800, Baolin Wang wrote:
>> Callers use ptep_test_and_clear_young() to clear the young flag and check
>> whether it was set. Change the return type to bool to make the intention
>> clearer.
>>
>> Signed-off-by: Baolin Wang <baolin.wang at linux.alibaba.com>
>
> Couple nits about dropping externs below but otherwise LGTM, so:
>
> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs at kernel.org>
Thanks for reviewing.
>> ---
>> arch/arm64/include/asm/pgtable.h | 8 ++++----
>> arch/arm64/mm/contpte.c | 4 ++--
>> arch/microblaze/include/asm/pgtable.h | 2 +-
>> arch/parisc/include/asm/pgtable.h | 6 +++---
>> arch/powerpc/include/asm/book3s/32/pgtable.h | 4 ++--
>> arch/powerpc/include/asm/book3s/64/pgtable.h | 6 +++---
>> arch/powerpc/include/asm/nohash/pgtable.h | 4 ++--
>> arch/riscv/include/asm/pgtable.h | 4 ++--
>> arch/riscv/mm/pgtable.c | 8 ++++----
>> arch/s390/include/asm/pgtable.h | 4 ++--
>> arch/x86/include/asm/pgtable.h | 4 ++--
>> arch/x86/mm/pgtable.c | 6 +++---
>> arch/xtensa/include/asm/pgtable.h | 6 +++---
>> include/linux/pgtable.h | 16 ++++++++--------
>> 14 files changed, 41 insertions(+), 41 deletions(-)
>>
>> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
>> index ab451d20e4c5..8c651695204c 100644
>> --- a/arch/arm64/include/asm/pgtable.h
>> +++ b/arch/arm64/include/asm/pgtable.h
>> @@ -1282,7 +1282,7 @@ static inline void __pte_clear(struct mm_struct *mm,
>> __set_pte(ptep, __pte(0));
>> }
>>
>> -static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma,
>> +static inline bool __ptep_test_and_clear_young(struct vm_area_struct *vma,
>> unsigned long address,
>> pte_t *ptep)
>> {
>> @@ -1646,7 +1646,7 @@ extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
>> extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
>> unsigned long addr, pte_t *ptep,
>> unsigned int nr, int full);
>> -int contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
>> +bool contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
>> unsigned long addr, pte_t *ptep, unsigned int nr);
>> int contpte_clear_flush_young_ptes(struct vm_area_struct *vma,
>> unsigned long addr, pte_t *ptep, unsigned int nr);
>> @@ -1813,7 +1813,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>> }
>>
>> #define test_and_clear_young_ptes test_and_clear_young_ptes
>> -static inline int test_and_clear_young_ptes(struct vm_area_struct *vma,
>> +static inline bool test_and_clear_young_ptes(struct vm_area_struct *vma,
>> unsigned long addr, pte_t *ptep,
>> unsigned int nr)
>> {
>> @@ -1824,7 +1824,7 @@ static inline int test_and_clear_young_ptes(struct vm_area_struct *vma,
>> }
>>
>> #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
>> -static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
>> +static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>> unsigned long addr, pte_t *ptep)
>> {
>> return test_and_clear_young_ptes(vma, addr, ptep, 1);
>> diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c
>> index 1519d090d5ea..0b88278927a4 100644
>> --- a/arch/arm64/mm/contpte.c
>> +++ b/arch/arm64/mm/contpte.c
>> @@ -508,7 +508,7 @@ pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
>> }
>> EXPORT_SYMBOL_GPL(contpte_get_and_clear_full_ptes);
>>
>> -int contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
>> +bool contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
>> unsigned long addr, pte_t *ptep,
>> unsigned int nr)
>> {
>> @@ -525,7 +525,7 @@ int contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
>> */
>>
>> unsigned long end = addr + nr * PAGE_SIZE;
>> - int young = 0;
>> + bool young = false;
>>
>> ptep = contpte_align_addr_ptep(&addr, &end, ptep, nr);
>> for (; addr != end; ptep++, addr += PAGE_SIZE)
>> diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h
>> index ea72291de553..7678c040a2fd 100644
>> --- a/arch/microblaze/include/asm/pgtable.h
>> +++ b/arch/microblaze/include/asm/pgtable.h
>> @@ -318,7 +318,7 @@ static inline void set_pte(pte_t *ptep, pte_t pte)
>>
>> #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
>> struct vm_area_struct;
>> -static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
>> +static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>> unsigned long address, pte_t *ptep)
>> {
>> return (pte_update(ptep, _PAGE_ACCESSED, 0) & _PAGE_ACCESSED) != 0;
>> diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
>> index f6fb99cb94d9..d5e39f2eb415 100644
>> --- a/arch/parisc/include/asm/pgtable.h
>> +++ b/arch/parisc/include/asm/pgtable.h
>> @@ -438,16 +438,16 @@ static inline pte_t ptep_get(pte_t *ptep)
>> }
>> #define ptep_get ptep_get
>>
>> -static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
>> +static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
>> {
>> pte_t pte;
>>
>> pte = ptep_get(ptep);
>> if (!pte_young(pte)) {
>> - return 0;
>> + return false;
>> }
>> set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
>> - return 1;
>> + return true;
>> }
>>
>> int ptep_clear_flush_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep);
>> diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
>> index 001e28f9eabc..2a889e2093e8 100644
>> --- a/arch/powerpc/include/asm/book3s/32/pgtable.h
>> +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
>> @@ -295,8 +295,8 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p
>> * for our hash-based implementation, we fix that up here.
>> */
>> #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
>> -static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
>> - unsigned long addr, pte_t *ptep)
>> +static inline bool __ptep_test_and_clear_young(struct mm_struct *mm,
>> + unsigned long addr, pte_t *ptep)
>> {
>> unsigned long old;
>> old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0);
>> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
>> index 1a91762b455d..25e3a86943e2 100644
>> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
>> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
>> @@ -349,13 +349,13 @@ static inline unsigned long pte_update(struct mm_struct *mm, unsigned long addr,
>> * For radix: H_PAGE_HASHPTE should be zero. Hence we can use the same
>> * function for both hash and radix.
>> */
>> -static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
>> - unsigned long addr, pte_t *ptep)
>> +static inline bool __ptep_test_and_clear_young(struct mm_struct *mm,
>> + unsigned long addr, pte_t *ptep)
>> {
>> unsigned long old;
>>
>> if ((pte_raw(*ptep) & cpu_to_be64(_PAGE_ACCESSED | H_PAGE_HASHPTE)) == 0)
>> - return 0;
>> + return false;
>> old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0);
>> return (old & _PAGE_ACCESSED) != 0;
>> }
>> diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
>> index e6da5eaccff6..43cf52f0c7d6 100644
>> --- a/arch/powerpc/include/asm/nohash/pgtable.h
>> +++ b/arch/powerpc/include/asm/nohash/pgtable.h
>> @@ -101,8 +101,8 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p
>> }
>> #endif
>>
>> -static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
>> - unsigned long addr, pte_t *ptep)
>> +static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>> + unsigned long addr, pte_t *ptep)
>> {
>> unsigned long old;
>>
>> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
>> index ab4ce1cc9d9c..fb010dcdf343 100644
>> --- a/arch/riscv/include/asm/pgtable.h
>> +++ b/arch/riscv/include/asm/pgtable.h
>> @@ -659,8 +659,8 @@ static inline void pte_clear(struct mm_struct *mm,
>> extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
>> pte_t *ptep, pte_t entry, int dirty);
>> #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG /* defined in mm/pgtable.c */
>> -extern int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long address,
>> - pte_t *ptep);
>> +extern bool ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long address,
>> + pte_t *ptep);
>
> Let's drop the extern.
Yes, I followed the original code style, but dropping the extern looks
reasonable to me. Will do.
>> #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
>> static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>> diff --git a/arch/riscv/mm/pgtable.c b/arch/riscv/mm/pgtable.c
>> index b1ed2f14dc3a..de24a19e8ebd 100644
>> --- a/arch/riscv/mm/pgtable.c
>> +++ b/arch/riscv/mm/pgtable.c
>> @@ -29,12 +29,12 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
>> return true;
>> }
>>
>> -int ptep_test_and_clear_young(struct vm_area_struct *vma,
>> - unsigned long address,
>> - pte_t *ptep)
>> +bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>> + unsigned long address,
>> + pte_t *ptep)
>> {
>> if (!pte_young(ptep_get(ptep)))
>> - return 0;
>> + return false;
>> return test_and_clear_bit(_PAGE_ACCESSED_OFFSET, &pte_val(*ptep));
>> }
>> EXPORT_SYMBOL_GPL(ptep_test_and_clear_young);
>> diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
>> index 1c3c3be93be9..da1a7a31fa22 100644
>> --- a/arch/s390/include/asm/pgtable.h
>> +++ b/arch/s390/include/asm/pgtable.h
>> @@ -1164,8 +1164,8 @@ pte_t ptep_xchg_direct(struct mm_struct *, unsigned long, pte_t *, pte_t);
>> pte_t ptep_xchg_lazy(struct mm_struct *, unsigned long, pte_t *, pte_t);
>>
>> #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
>> -static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
>> - unsigned long addr, pte_t *ptep)
>> +static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>> + unsigned long addr, pte_t *ptep)
>> {
>> pte_t pte = *ptep;
>>
>> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
>> index 54289f4587a4..563a6289ea44 100644
>> --- a/arch/x86/include/asm/pgtable.h
>> +++ b/arch/x86/include/asm/pgtable.h
>> @@ -1232,8 +1232,8 @@ extern int ptep_set_access_flags(struct vm_area_struct *vma,
>> pte_t entry, int dirty);
>>
>> #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
>> -extern int ptep_test_and_clear_young(struct vm_area_struct *vma,
>> - unsigned long addr, pte_t *ptep);
>> +extern bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>> + unsigned long addr, pte_t *ptep);
>
> Let's drop the extern.
Ack.
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