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[PATCH 3/6] mm: change to return bool for pmdp_test_and_clear_young()

Baolin Wang posted 6 patches 2 weeks, 6 days ago
There is a newer version of this series
[PATCH 3/6] mm: change to return bool for pmdp_test_and_clear_young()
Posted by Baolin Wang 2 weeks, 6 days ago 
Callers use pmdp_test_and_clear_young() to clear the young flag and check
whether it was set for this PMD entry. Change the return type to bool to
make the intention clearer.

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
 arch/arm64/include/asm/pgtable.h             |  6 +++---
 arch/powerpc/include/asm/book3s/64/pgtable.h | 10 +++++-----
 arch/powerpc/mm/book3s64/pgtable.c           |  4 ++--
 arch/riscv/include/asm/pgtable.h             |  2 +-
 arch/s390/include/asm/pgtable.h              |  4 ++--
 arch/x86/include/asm/pgtable.h               |  4 ++--
 arch/x86/mm/pgtable.c                        |  6 +++---
 include/linux/pgtable.h                      | 19 +++++++++----------
 8 files changed, 27 insertions(+), 28 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 393a9d1873f6..7ea16f6ad564 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -1321,9 +1321,9 @@ static inline bool __ptep_clear_flush_young(struct vm_area_struct *vma,
 
 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
-static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-					    unsigned long address,
-					    pmd_t *pmdp)
+static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
+					     unsigned long address,
+					     pmd_t *pmdp)
 {
 	/* Operation applies to PMD table entry only if FEAT_HAFT is enabled */
 	VM_WARN_ON(pmd_table(READ_ONCE(*pmdp)) && !system_supports_haft());
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 25e3a86943e2..0f34011665a6 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -1161,13 +1161,13 @@ pud_hugepage_update(struct mm_struct *mm, unsigned long addr, pud_t *pudp,
  * For radix we should always find H_PAGE_HASHPTE zero. Hence
  * the below will work for radix too
  */
-static inline int __pmdp_test_and_clear_young(struct mm_struct *mm,
-					      unsigned long addr, pmd_t *pmdp)
+static inline bool __pmdp_test_and_clear_young(struct mm_struct *mm,
+					       unsigned long addr, pmd_t *pmdp)
 {
 	unsigned long old;
 
 	if ((pmd_raw(*pmdp) & cpu_to_be64(_PAGE_ACCESSED | H_PAGE_HASHPTE)) == 0)
-		return 0;
+		return false;
 	old = pmd_hugepage_update(mm, addr, pmdp, _PAGE_ACCESSED, 0);
 	return ((old & _PAGE_ACCESSED) != 0);
 }
@@ -1300,8 +1300,8 @@ extern int pudp_set_access_flags(struct vm_area_struct *vma,
 				 pud_t entry, int dirty);
 
 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
-extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-				     unsigned long address, pmd_t *pmdp);
+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);
diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
index 4b09c04654a8..aed39bba891e 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -98,8 +98,8 @@ int pudp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
 }
 
 
-int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-			      unsigned long address, pmd_t *pmdp)
+bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
+			       unsigned long address, pmd_t *pmdp)
 {
 	return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp);
 }
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 11f57ccf6dc9..bac559d29036 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -1015,7 +1015,7 @@ static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
 }
 
 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
-static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
+static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
 					unsigned long address, pmd_t *pmdp)
 {
 	return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index c9ab81caaf75..1f5efb7be71d 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1683,8 +1683,8 @@ static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
 }
 
 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
-static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-					    unsigned long addr, pmd_t *pmdp)
+static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
+					     unsigned long addr, pmd_t *pmdp)
 {
 	pmd_t pmd = *pmdp;
 
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 554dea93eb99..bd02ee730a23 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1295,8 +1295,8 @@ extern int pudp_set_access_flags(struct vm_area_struct *vma,
 				 pud_t entry, int dirty);
 
 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
-extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-				     unsigned long addr, pmd_t *pmdp);
+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);
 
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 0007dc3d739e..10a5e0b2be36 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -456,10 +456,10 @@ bool ptep_test_and_clear_young(struct vm_area_struct *vma,
 }
 
 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
-int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-			      unsigned long addr, pmd_t *pmdp)
+bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
+			       unsigned long addr, pmd_t *pmdp)
 {
-	int ret = 0;
+	bool ret = false;
 
 	if (pmd_young(*pmdp))
 		ret = test_and_clear_bit(_PAGE_BIT_ACCESSED,
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 1198e216fde3..e53220b0a9a3 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -507,25 +507,24 @@ static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
 
 #ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
-static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-					    unsigned long address,
-					    pmd_t *pmdp)
+static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
+		unsigned long address, pmd_t *pmdp)
 {
 	pmd_t pmd = *pmdp;
-	int r = 1;
+	bool young = true;
+
 	if (!pmd_young(pmd))
-		r = 0;
+		young = false;
 	else
 		set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd));
-	return r;
+	return young;
 }
 #else
-static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
-					    unsigned long address,
-					    pmd_t *pmdp)
+static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
+		unsigned long address, pmd_t *pmdp)
 {
 	BUILD_BUG();
-	return 0;
+	return false;
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG */
 #endif
-- 
2.47.3
Re: [PATCH 3/6] mm: change to return bool for pmdp_test_and_clear_young()
Posted by Ritesh Harjani (IBM) 2 weeks, 4 days ago 
Baolin Wang <baolin.wang@linux.alibaba.com> writes:

> Callers use pmdp_test_and_clear_young() to clear the young flag and check
> whether it was set for this PMD entry. Change the return type to bool to
> make the intention clearer.
>
> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
> ---
>  arch/arm64/include/asm/pgtable.h             |  6 +++---
>  arch/powerpc/include/asm/book3s/64/pgtable.h | 10 +++++-----
>  arch/powerpc/mm/book3s64/pgtable.c           |  4 ++--
>  arch/riscv/include/asm/pgtable.h             |  2 +-
>  arch/s390/include/asm/pgtable.h              |  4 ++--
>  arch/x86/include/asm/pgtable.h               |  4 ++--
>  arch/x86/mm/pgtable.c                        |  6 +++---
>  include/linux/pgtable.h                      | 19 +++++++++----------
>  8 files changed, 27 insertions(+), 28 deletions(-)
>

LGTM. Please feel free to add:
(assuming you will anyway kill the unwanted externs)

Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Re: [PATCH 3/6] mm: change to return bool for pmdp_test_and_clear_young()
Posted by Lorenzo Stoakes (Oracle) 2 weeks, 5 days ago 
On Thu, Mar 19, 2026 at 11:24:02AM +0800, Baolin Wang wrote:
> Callers use pmdp_test_and_clear_young() to clear the young flag and check
> whether it was set for this PMD entry. Change the return type to bool to
> make the intention clearer.
>
> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>

Some nits similar to before, otherwise LGTM so:

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

> ---
>  arch/arm64/include/asm/pgtable.h             |  6 +++---
>  arch/powerpc/include/asm/book3s/64/pgtable.h | 10 +++++-----
>  arch/powerpc/mm/book3s64/pgtable.c           |  4 ++--
>  arch/riscv/include/asm/pgtable.h             |  2 +-
>  arch/s390/include/asm/pgtable.h              |  4 ++--
>  arch/x86/include/asm/pgtable.h               |  4 ++--
>  arch/x86/mm/pgtable.c                        |  6 +++---
>  include/linux/pgtable.h                      | 19 +++++++++----------
>  8 files changed, 27 insertions(+), 28 deletions(-)
>
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 393a9d1873f6..7ea16f6ad564 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -1321,9 +1321,9 @@ static inline bool __ptep_clear_flush_young(struct vm_area_struct *vma,
>
>  #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
>  #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
> -static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -					    unsigned long address,
> -					    pmd_t *pmdp)
> +static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +					     unsigned long address,
> +					     pmd_t *pmdp)

Similar comment as before re: indetation, let's use 2 tabs please, so this would
become:

static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
		unsigned long address, pmd_t *pmdp)

Thanks!

Same comment to all other cases here.

>  {
>  	/* Operation applies to PMD table entry only if FEAT_HAFT is enabled */
>  	VM_WARN_ON(pmd_table(READ_ONCE(*pmdp)) && !system_supports_haft());
> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
> index 25e3a86943e2..0f34011665a6 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
> @@ -1161,13 +1161,13 @@ pud_hugepage_update(struct mm_struct *mm, unsigned long addr, pud_t *pudp,
>   * For radix we should always find H_PAGE_HASHPTE zero. Hence
>   * the below will work for radix too
>   */
> -static inline int __pmdp_test_and_clear_young(struct mm_struct *mm,
> -					      unsigned long addr, pmd_t *pmdp)
> +static inline bool __pmdp_test_and_clear_young(struct mm_struct *mm,
> +					       unsigned long addr, pmd_t *pmdp)
>  {
>  	unsigned long old;
>
>  	if ((pmd_raw(*pmdp) & cpu_to_be64(_PAGE_ACCESSED | H_PAGE_HASHPTE)) == 0)
> -		return 0;
> +		return false;
>  	old = pmd_hugepage_update(mm, addr, pmdp, _PAGE_ACCESSED, 0);
>  	return ((old & _PAGE_ACCESSED) != 0);
>  }
> @@ -1300,8 +1300,8 @@ extern int pudp_set_access_flags(struct vm_area_struct *vma,
>  				 pud_t entry, int dirty);
>
>  #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
> -extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -				     unsigned long address, pmd_t *pmdp);
> +extern bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +				      unsigned long address, pmd_t *pmdp);

Remove the extern please!

>  #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);
> diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
> index 4b09c04654a8..aed39bba891e 100644
> --- a/arch/powerpc/mm/book3s64/pgtable.c
> +++ b/arch/powerpc/mm/book3s64/pgtable.c
> @@ -98,8 +98,8 @@ int pudp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
>  }
>
>
> -int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -			      unsigned long address, pmd_t *pmdp)
> +bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +			       unsigned long address, pmd_t *pmdp)
>  {
>  	return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp);
>  }
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index 11f57ccf6dc9..bac559d29036 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -1015,7 +1015,7 @@ static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
>  }
>
>  #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
> -static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
>  					unsigned long address, pmd_t *pmdp)
>  {
>  	return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
> diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
> index c9ab81caaf75..1f5efb7be71d 100644
> --- a/arch/s390/include/asm/pgtable.h
> +++ b/arch/s390/include/asm/pgtable.h
> @@ -1683,8 +1683,8 @@ static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
>  }
>
>  #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
> -static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -					    unsigned long addr, pmd_t *pmdp)
> +static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +					     unsigned long addr, pmd_t *pmdp)
>  {
>  	pmd_t pmd = *pmdp;
>
> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> index 554dea93eb99..bd02ee730a23 100644
> --- a/arch/x86/include/asm/pgtable.h
> +++ b/arch/x86/include/asm/pgtable.h
> @@ -1295,8 +1295,8 @@ extern int pudp_set_access_flags(struct vm_area_struct *vma,
>  				 pud_t entry, int dirty);
>
>  #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
> -extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -				     unsigned long addr, pmd_t *pmdp);
> +extern bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +				      unsigned long addr, pmd_t *pmdp);

Remove the extern please!

>  extern int pudp_test_and_clear_young(struct vm_area_struct *vma,
>  				     unsigned long addr, pud_t *pudp);
>
> diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
> index 0007dc3d739e..10a5e0b2be36 100644
> --- a/arch/x86/mm/pgtable.c
> +++ b/arch/x86/mm/pgtable.c
> @@ -456,10 +456,10 @@ bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>  }
>
>  #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
> -int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -			      unsigned long addr, pmd_t *pmdp)
> +bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +			       unsigned long addr, pmd_t *pmdp)
>  {
> -	int ret = 0;
> +	bool ret = false;
>
>  	if (pmd_young(*pmdp))
>  		ret = test_and_clear_bit(_PAGE_BIT_ACCESSED,
> diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
> index 1198e216fde3..e53220b0a9a3 100644
> --- a/include/linux/pgtable.h
> +++ b/include/linux/pgtable.h
> @@ -507,25 +507,24 @@ static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
>
>  #ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
>  #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
> -static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -					    unsigned long address,
> -					    pmd_t *pmdp)
> +static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +		unsigned long address, pmd_t *pmdp)
>  {
>  	pmd_t pmd = *pmdp;
> -	int r = 1;
> +	bool young = true;
> +
>  	if (!pmd_young(pmd))
> -		r = 0;
> +		young = false;
>  	else
>  		set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd));
> -	return r;
> +	return young;
>  }
>  #else
> -static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
> -					    unsigned long address,
> -					    pmd_t *pmdp)
> +static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
> +		unsigned long address, pmd_t *pmdp)
>  {
>  	BUILD_BUG();
> -	return 0;
> +	return false;
>  }
>  #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG */
>  #endif
> --
> 2.47.3
>
Re: [PATCH 3/6] mm: change to return bool for pmdp_test_and_clear_young()
Posted by Baolin Wang 2 weeks, 5 days ago 

On 3/19/26 7:31 PM, Lorenzo Stoakes (Oracle) wrote:
> On Thu, Mar 19, 2026 at 11:24:02AM +0800, Baolin Wang wrote:
>> Callers use pmdp_test_and_clear_young() to clear the young flag and check
>> whether it was set for this PMD entry. Change the return type to bool to
>> make the intention clearer.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
> 
> Some nits similar to before, otherwise LGTM so:
> 
> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>

Thanks. And all comments acked.

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