(sashiko review) Re: [PATCH v4 7/9] treewide: introduce arch_has_pmd_leaves()

[Luiz Capitulino <luizcap@redhat.com>]

On 2026-05-01 15:18, Luiz Capitulino wrote:
> Now that all the has_transparent_hugepage() callers have been converted
> to pgtable_has_pmd_leaves(), this commit does two things:
> 
> 1. Rename has_transparent_hugepage() arch implementations to
>     arch_has_pmd_leaves(), since that's what the helper checks for
> 
> 2. Introduce the default implementation of arch_has_pmd_leaves() as
>     IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE). This means that if
>     the arch doesn't implement arch_has_pmd_leaves() we default to checking
>     CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE as a way to determine if
>     PMD-sized pages are supported
> 
> Note that arch_has_pmd_leaves() is supposed to be called only by
> init_arch_has_pmd_leaves(). The remaining exception is hugepage_init()
> which will be converted in a future commit.
> 
> Signed-off-by: Luiz Capitulino <luizcap@redhat.com>
> ---
>   arch/mips/include/asm/pgtable.h               |  4 ++--
>   arch/mips/mm/tlb-r4k.c                        |  4 ++--
>   arch/powerpc/include/asm/book3s/64/hash-4k.h  |  2 +-
>   arch/powerpc/include/asm/book3s/64/hash-64k.h |  2 +-
>   arch/powerpc/include/asm/book3s/64/pgtable.h  | 10 +++++-----
>   arch/powerpc/include/asm/book3s/64/radix.h    |  2 +-
>   arch/powerpc/mm/book3s64/hash_pgtable.c       |  4 ++--
>   arch/s390/include/asm/pgtable.h               |  4 ++--
>   arch/x86/include/asm/pgtable.h                |  4 ++--
>   include/linux/pgtable.h                       |  4 ++--
>   mm/huge_memory.c                              |  2 +-
>   mm/memory.c                                   |  2 +-
>   12 files changed, 22 insertions(+), 22 deletions(-)
> 
> diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
> index fa7b935f947c..a97b788315e2 100644
> --- a/arch/mips/include/asm/pgtable.h
> +++ b/arch/mips/include/asm/pgtable.h
> @@ -615,8 +615,8 @@ unsigned long io_remap_pfn_range_pfn(unsigned long pfn, unsigned long size);
>   /* We don't have hardware dirty/accessed bits, generic_pmdp_establish is fine.*/
>   #define pmdp_establish generic_pmdp_establish
>   
> -#define has_transparent_hugepage has_transparent_hugepage
> -extern int has_transparent_hugepage(void);
> +#define arch_has_pmd_leaves arch_has_pmd_leaves
> +extern int arch_has_pmd_leaves(void);
>   
>   static inline int pmd_trans_huge(pmd_t pmd)
>   {
> diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c
> index 24fe85fa169d..c423b5784337 100644
> --- a/arch/mips/mm/tlb-r4k.c
> +++ b/arch/mips/mm/tlb-r4k.c
> @@ -434,7 +434,7 @@ void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1,
>   
>   #ifdef CONFIG_TRANSPARENT_HUGEPAGE
>   
> -int has_transparent_hugepage(void)
> +int arch_has_pmd_leaves(void)
>   {
>   	static unsigned int mask = -1;
>   
> @@ -450,7 +450,7 @@ int has_transparent_hugepage(void)
>   	}
>   	return mask == PM_HUGE_MASK;
>   }
> -EXPORT_SYMBOL(has_transparent_hugepage);
> +EXPORT_SYMBOL(arch_has_pmd_leaves);
>   
>   #endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
>   
> diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> index 8e5bd9902bed..6744c2287199 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
> @@ -165,7 +165,7 @@ extern void hash__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
>   extern pgtable_t hash__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
>   extern pmd_t hash__pmdp_huge_get_and_clear(struct mm_struct *mm,
>   				       unsigned long addr, pmd_t *pmdp);
> -extern int hash__has_transparent_hugepage(void);
> +extern int hash__arch_has_pmd_leaves(void);
>   #endif
>   
>   #endif /* !__ASSEMBLER__ */
> diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> index 7deb3a66890b..9392aba5e5dc 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> @@ -278,7 +278,7 @@ extern void hash__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
>   extern pgtable_t hash__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
>   extern pmd_t hash__pmdp_huge_get_and_clear(struct mm_struct *mm,
>   				       unsigned long addr, pmd_t *pmdp);
> -extern int hash__has_transparent_hugepage(void);
> +extern int hash__arch_has_pmd_leaves(void);
>   #endif /*  CONFIG_TRANSPARENT_HUGEPAGE */
>   
>   #endif	/* __ASSEMBLER__ */
> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
> index e67e64ac6e8c..b6629c041e75 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
> @@ -1121,14 +1121,14 @@ static inline void update_mmu_cache_pud(struct vm_area_struct *vma,
>   {
>   }
>   
> -extern int hash__has_transparent_hugepage(void);
> -static inline int has_transparent_hugepage(void)
> +extern int hash__arch_has_pmd_leaves(void);
> +static inline int arch_has_pmd_leaves(void)
>   {
>   	if (radix_enabled())
> -		return radix__has_transparent_hugepage();
> -	return hash__has_transparent_hugepage();
> +		return radix__arch_has_pmd_leaves();
> +	return hash__arch_has_pmd_leaves();
>   }
> -#define has_transparent_hugepage has_transparent_hugepage
> +#define arch_has_pmd_leaves arch_has_pmd_leaves
>   
>   static inline int has_transparent_pud_hugepage(void)
>   {
> diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h
> index da954e779744..c884a119cbd9 100644
> --- a/arch/powerpc/include/asm/book3s/64/radix.h
> +++ b/arch/powerpc/include/asm/book3s/64/radix.h
> @@ -298,7 +298,7 @@ extern pmd_t radix__pmdp_huge_get_and_clear(struct mm_struct *mm,
>   pud_t radix__pudp_huge_get_and_clear(struct mm_struct *mm,
>   				     unsigned long addr, pud_t *pudp);
>   
> -static inline int radix__has_transparent_hugepage(void)
> +static inline int radix__arch_has_pmd_leaves(void)
>   {
>   	/* For radix 2M at PMD level means thp */
>   	if (mmu_psize_defs[MMU_PAGE_2M].shift == PMD_SHIFT)
> diff --git a/arch/powerpc/mm/book3s64/hash_pgtable.c b/arch/powerpc/mm/book3s64/hash_pgtable.c
> index d9b5b751d7b7..88a4a2eab513 100644
> --- a/arch/powerpc/mm/book3s64/hash_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/hash_pgtable.c
> @@ -391,7 +391,7 @@ pmd_t hash__pmdp_huge_get_and_clear(struct mm_struct *mm,
>   	return old_pmd;
>   }
>   
> -int hash__has_transparent_hugepage(void)
> +int hash__arch_has_pmd_leaves(void)
>   {
>   
>   	if (!mmu_has_feature(MMU_FTR_16M_PAGE))
> @@ -420,7 +420,7 @@ int hash__has_transparent_hugepage(void)
>   
>   	return 1;
>   }
> -EXPORT_SYMBOL_GPL(hash__has_transparent_hugepage);
> +EXPORT_SYMBOL_GPL(hash__arch_has_pmd_leaves);
>   
>   #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>   
> diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
> index 2c6cee8241e0..33b165dbf3db 100644
> --- a/arch/s390/include/asm/pgtable.h
> +++ b/arch/s390/include/asm/pgtable.h
> @@ -1799,8 +1799,8 @@ static inline int pmd_trans_huge(pmd_t pmd)
>   	return pmd_leaf(pmd);
>   }
>   
> -#define has_transparent_hugepage has_transparent_hugepage
> -static inline int has_transparent_hugepage(void)
> +#define arch_has_pmd_leaves arch_has_pmd_leaves
> +static inline int arch_has_pmd_leaves(void)
>   {
>   	return cpu_has_edat1() ? 1 : 0;
>   }
> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> index 2187e9cfcefa..2edd6c9d789c 100644
> --- a/arch/x86/include/asm/pgtable.h
> +++ b/arch/x86/include/asm/pgtable.h
> @@ -306,8 +306,8 @@ static inline int pud_trans_huge(pud_t pud)
>   }
>   #endif
>   
> -#define has_transparent_hugepage has_transparent_hugepage
> -static inline int has_transparent_hugepage(void)
> +#define arch_has_pmd_leaves arch_has_pmd_leaves
> +static inline int arch_has_pmd_leaves(void)
>   {
>   	return boot_cpu_has(X86_FEATURE_PSE);
>   }
> diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
> index b365be3516bf..3d7eeb50c183 100644
> --- a/include/linux/pgtable.h
> +++ b/include/linux/pgtable.h
> @@ -2273,8 +2273,8 @@ static inline void __init init_arch_has_pmd_leaves(void) { }
>   #endif
>   #endif
>   
> -#ifndef has_transparent_hugepage
> -#define has_transparent_hugepage() IS_BUILTIN(CONFIG_TRANSPARENT_HUGEPAGE)
> +#ifndef arch_has_pmd_leaves
> +#define arch_has_pmd_leaves() IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE)
>   #endif
>   
>   #ifndef has_transparent_pud_hugepage
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 970e077019b7..4da10e94bbb6 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -969,7 +969,7 @@ static int __init hugepage_init(void)
>   	int err;
>   	struct kobject *hugepage_kobj;
>   
> -	if (!has_transparent_hugepage()) {
> +	if (!arch_has_pmd_leaves()) {
>   		transparent_hugepage_flags = 1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED;
>   		return -EINVAL;
>   	}
> diff --git a/mm/memory.c b/mm/memory.c
> index 90b2d9e84320..c62fce83b8d0 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -169,7 +169,7 @@ EXPORT_SYMBOL(__arch_has_pmd_leaves_key);
>   
>   void __init init_arch_has_pmd_leaves(void)
>   {
> -	if (!has_transparent_hugepage())
> +	if (!arch_has_pmd_leaves())
>   		static_branch_disable(&__arch_has_pmd_leaves_key);
>   }
>