From: Peter Xu <peterx@redhat.com>

This API is not used anymore, drop it for the whole tree.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 arch/arm/mm/Makefile                          |  1 -
 arch/arm/mm/hugetlbpage.c                     | 29 -------------------
 arch/arm64/mm/hugetlbpage.c                   | 10 -------
 arch/loongarch/mm/hugetlbpage.c               | 10 -------
 arch/mips/include/asm/pgtable-32.h            |  2 +-
 arch/mips/include/asm/pgtable-64.h            |  2 +-
 arch/mips/mm/hugetlbpage.c                    | 10 -------
 arch/parisc/mm/hugetlbpage.c                  | 11 -------
 .../include/asm/book3s/64/pgtable-4k.h        | 10 -------
 .../include/asm/book3s/64/pgtable-64k.h       | 25 ----------------
 arch/powerpc/include/asm/nohash/pgtable.h     | 10 -------
 arch/riscv/mm/hugetlbpage.c                   | 10 -------
 arch/s390/mm/hugetlbpage.c                    | 10 -------
 arch/sh/mm/hugetlbpage.c                      | 10 -------
 arch/sparc/mm/hugetlbpage.c                   | 10 -------
 arch/x86/mm/hugetlbpage.c                     | 16 ----------
 include/linux/hugetlb.h                       | 24 ---------------
 17 files changed, 2 insertions(+), 198 deletions(-)
 delete mode 100644 arch/arm/mm/hugetlbpage.c

diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index 71b858c9b10c..1779e12db085 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -21,7 +21,6 @@ KASAN_SANITIZE_physaddr.o	:= n
 obj-$(CONFIG_DEBUG_VIRTUAL)	+= physaddr.o
 
 obj-$(CONFIG_ALIGNMENT_TRAP)	+= alignment.o
-obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o
 obj-$(CONFIG_ARM_PV_FIXUP)	+= pv-fixup-asm.o
 
 obj-$(CONFIG_CPU_ABRT_NOMMU)	+= abort-nommu.o
diff --git a/arch/arm/mm/hugetlbpage.c b/arch/arm/mm/hugetlbpage.c
deleted file mode 100644
index c2fa643f6bb5..000000000000
--- a/arch/arm/mm/hugetlbpage.c
+++ /dev/null
@@ -1,29 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * arch/arm/mm/hugetlbpage.c
- *
- * Copyright (C) 2012 ARM Ltd.
- *
- * Based on arch/x86/include/asm/hugetlb.h and Bill Carson's patches
- */
-
-#include <linux/init.h>
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/hugetlb.h>
-#include <linux/pagemap.h>
-#include <linux/err.h>
-#include <linux/sysctl.h>
-#include <asm/mman.h>
-#include <asm/tlb.h>
-#include <asm/tlbflush.h>
-
-int pud_huge(pud_t pud)
-{
-	return 0;
-}
-
-int pmd_huge(pmd_t pmd)
-{
-	return pmd_leaf(pmd);
-}
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index f494fc31201f..ca58210d6c07 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -79,16 +79,6 @@ bool arch_hugetlb_migration_supported(struct hstate *h)
 }
 #endif
 
-int pmd_huge(pmd_t pmd)
-{
-	return pmd_leaf(pmd);
-}
-
-int pud_huge(pud_t pud)
-{
-	return pud_leaf(pud);
-}
-
 static int find_num_contig(struct mm_struct *mm, unsigned long addr,
 			   pte_t *ptep, size_t *pgsize)
 {
diff --git a/arch/loongarch/mm/hugetlbpage.c b/arch/loongarch/mm/hugetlbpage.c
index a4e78e74aa21..12222c56cb59 100644
--- a/arch/loongarch/mm/hugetlbpage.c
+++ b/arch/loongarch/mm/hugetlbpage.c
@@ -50,16 +50,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
 	return (pte_t *) pmd;
 }
 
-int pmd_huge(pmd_t pmd)
-{
-	return (pmd_val(pmd) & _PAGE_HUGE) != 0;
-}
-
-int pud_huge(pud_t pud)
-{
-	return (pud_val(pud) & _PAGE_HUGE) != 0;
-}
-
 uint64_t pmd_to_entrylo(unsigned long pmd_val)
 {
 	uint64_t val;
diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h
index 0e196650f4f4..92b7591aac2a 100644
--- a/arch/mips/include/asm/pgtable-32.h
+++ b/arch/mips/include/asm/pgtable-32.h
@@ -129,7 +129,7 @@ static inline int pmd_none(pmd_t pmd)
 static inline int pmd_bad(pmd_t pmd)
 {
 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
-	/* pmd_huge(pmd) but inline */
+	/* pmd_leaf(pmd) but inline */
 	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
 		return 0;
 #endif
diff --git a/arch/mips/include/asm/pgtable-64.h b/arch/mips/include/asm/pgtable-64.h
index 20ca48c1b606..7c28510b3768 100644
--- a/arch/mips/include/asm/pgtable-64.h
+++ b/arch/mips/include/asm/pgtable-64.h
@@ -245,7 +245,7 @@ static inline int pmd_none(pmd_t pmd)
 static inline int pmd_bad(pmd_t pmd)
 {
 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
-	/* pmd_huge(pmd) but inline */
+	/* pmd_leaf(pmd) but inline */
 	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
 		return 0;
 #endif
diff --git a/arch/mips/mm/hugetlbpage.c b/arch/mips/mm/hugetlbpage.c
index 7eaff5b07873..0b9e15555b59 100644
--- a/arch/mips/mm/hugetlbpage.c
+++ b/arch/mips/mm/hugetlbpage.c
@@ -57,13 +57,3 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
 	}
 	return (pte_t *) pmd;
 }
-
-int pmd_huge(pmd_t pmd)
-{
-	return (pmd_val(pmd) & _PAGE_HUGE) != 0;
-}
-
-int pud_huge(pud_t pud)
-{
-	return (pud_val(pud) & _PAGE_HUGE) != 0;
-}
diff --git a/arch/parisc/mm/hugetlbpage.c b/arch/parisc/mm/hugetlbpage.c
index a9f7e21f6656..0356199bd9e7 100644
--- a/arch/parisc/mm/hugetlbpage.c
+++ b/arch/parisc/mm/hugetlbpage.c
@@ -180,14 +180,3 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 	}
 	return changed;
 }
-
-
-int pmd_huge(pmd_t pmd)
-{
-	return 0;
-}
-
-int pud_huge(pud_t pud)
-{
-	return 0;
-}
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable-4k.h b/arch/powerpc/include/asm/book3s/64/pgtable-4k.h
index 92545981bb49..baf934578c3a 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable-4k.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable-4k.h
@@ -6,16 +6,6 @@
  */
 #ifndef __ASSEMBLY__
 #ifdef CONFIG_HUGETLB_PAGE
-static inline int pmd_huge(pmd_t pmd)
-{
-	return pmd_leaf(pmd);
-}
-
-static inline int pud_huge(pud_t pud)
-{
-	return pud_leaf(pud);
-}
-
 /*
  * With radix , we have hugepage ptes in the pud and pmd entries. We don't
  * need to setup hugepage directory for them. Our pte and page directory format
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable-64k.h b/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
index 2fce3498b000..579a7153857f 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
@@ -4,31 +4,6 @@
 
 #ifndef __ASSEMBLY__
 #ifdef CONFIG_HUGETLB_PAGE
-/*
- * We have PGD_INDEX_SIZ = 12 and PTE_INDEX_SIZE = 8, so that we can have
- * 16GB hugepage pte in PGD and 16MB hugepage pte at PMD;
- *
- * Defined in such a way that we can optimize away code block at build time
- * if CONFIG_HUGETLB_PAGE=n.
- *
- * returns true for pmd migration entries, THP, devmap, hugetlb
- * But compile time dependent on CONFIG_HUGETLB_PAGE
- */
-static inline int pmd_huge(pmd_t pmd)
-{
-	/*
-	 * leaf pte for huge page
-	 */
-	return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE));
-}
-
-static inline int pud_huge(pud_t pud)
-{
-	/*
-	 * leaf pte for huge page
-	 */
-	return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE));
-}
 
 /*
  * With 64k page size, we have hugepage ptes in the pgd and pmd entries. We don't
diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index 427db14292c9..f5f39d4f03c8 100644
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h
@@ -351,16 +351,6 @@ static inline int hugepd_ok(hugepd_t hpd)
 #endif
 }
 
-static inline int pmd_huge(pmd_t pmd)
-{
-	return 0;
-}
-
-static inline int pud_huge(pud_t pud)
-{
-	return 0;
-}
-
 #define is_hugepd(hpd)		(hugepd_ok(hpd))
 #endif
 
diff --git a/arch/riscv/mm/hugetlbpage.c b/arch/riscv/mm/hugetlbpage.c
index 29c7606414d2..9a4bc4bd2a01 100644
--- a/arch/riscv/mm/hugetlbpage.c
+++ b/arch/riscv/mm/hugetlbpage.c
@@ -399,16 +399,6 @@ static bool is_napot_size(unsigned long size)
 
 #endif /*CONFIG_RISCV_ISA_SVNAPOT*/
 
-int pud_huge(pud_t pud)
-{
-	return pud_leaf(pud);
-}
-
-int pmd_huge(pmd_t pmd)
-{
-	return pmd_leaf(pmd);
-}
-
 static bool __hugetlb_valid_size(unsigned long size)
 {
 	if (size == HPAGE_SIZE)
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index c2e8242bd15d..ca43b6fce71c 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -233,16 +233,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
 	return (pte_t *) pmdp;
 }
 
-int pmd_huge(pmd_t pmd)
-{
-	return pmd_leaf(pmd);
-}
-
-int pud_huge(pud_t pud)
-{
-	return pud_leaf(pud);
-}
-
 bool __init arch_hugetlb_valid_size(unsigned long size)
 {
 	if (MACHINE_HAS_EDAT1 && size == PMD_SIZE)
diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c
index 6cb0ad73dbb9..ff209b55285a 100644
--- a/arch/sh/mm/hugetlbpage.c
+++ b/arch/sh/mm/hugetlbpage.c
@@ -70,13 +70,3 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
 
 	return pte;
 }
-
-int pmd_huge(pmd_t pmd)
-{
-	return 0;
-}
-
-int pud_huge(pud_t pud)
-{
-	return 0;
-}
diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
index d31c2cec35c9..8ed5bdf95d25 100644
--- a/arch/sparc/mm/hugetlbpage.c
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -407,16 +407,6 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 	return entry;
 }
 
-int pmd_huge(pmd_t pmd)
-{
-	return pmd_leaf(pmd);;
-}
-
-int pud_huge(pud_t pud)
-{
-	return pud_leaf(pud);
-}
-
 static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
 			   unsigned long addr)
 {
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 8362953a24ce..dab6db288e5b 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -19,22 +19,6 @@
 #include <asm/tlbflush.h>
 #include <asm/elf.h>
 
-/*
- * pmd_huge() returns 1 if @pmd is hugetlb related entry.
- */
-int pmd_huge(pmd_t pmd)
-{
-	return pmd_leaf(pmd);
-}
-
-/*
- * pud_huge() returns 1 if @pud is hugetlb related entry.
- */
-int pud_huge(pud_t pud)
-{
-	return pud_leaf(pud);
-}
-
 #ifdef CONFIG_HUGETLB_PAGE
 static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
 		unsigned long addr, unsigned long len,
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 77b30a8c6076..300de33c6fde 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -272,13 +272,9 @@ void hugetlb_vma_unlock_write(struct vm_area_struct *vma);
 int hugetlb_vma_trylock_write(struct vm_area_struct *vma);
 void hugetlb_vma_assert_locked(struct vm_area_struct *vma);
 void hugetlb_vma_lock_release(struct kref *kref);
-
-int pmd_huge(pmd_t pmd);
-int pud_huge(pud_t pud);
 long hugetlb_change_protection(struct vm_area_struct *vma,
 		unsigned long address, unsigned long end, pgprot_t newprot,
 		unsigned long cp_flags);
-
 bool is_hugetlb_entry_migration(pte_t pte);
 bool is_hugetlb_entry_hwpoisoned(pte_t pte);
 void hugetlb_unshare_all_pmds(struct vm_area_struct *vma);
@@ -399,16 +395,6 @@ static inline void hugetlb_vma_assert_locked(struct vm_area_struct *vma)
 {
 }
 
-static inline int pmd_huge(pmd_t pmd)
-{
-	return 0;
-}
-
-static inline int pud_huge(pud_t pud)
-{
-	return 0;
-}
-
 static inline int is_hugepage_only_range(struct mm_struct *mm,
 					unsigned long addr, unsigned long len)
 {
@@ -493,16 +479,6 @@ static inline vm_fault_t hugetlb_fault(struct mm_struct *mm,
 static inline void hugetlb_unshare_all_pmds(struct vm_area_struct *vma) { }
 
 #endif /* !CONFIG_HUGETLB_PAGE */
-/*
- * hugepages at page global directory. If arch support
- * hugepages at pgd level, they need to define this.
- */
-#ifndef pgd_huge
-#define pgd_huge(x)	0
-#endif
-#ifndef p4d_huge
-#define p4d_huge(x)	0
-#endif
 
 #ifndef pgd_write
 static inline int pgd_write(pgd_t pgd)
-- 
2.44.0

Le 13/03/2024 à 22:47, peterx@redhat.com a écrit :
> From: Peter Xu <peterx@redhat.com>
> 
> This API is not used anymore, drop it for the whole tree.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>   arch/arm/mm/Makefile                          |  1 -
>   arch/arm/mm/hugetlbpage.c                     | 29 -------------------
>   arch/arm64/mm/hugetlbpage.c                   | 10 -------
>   arch/loongarch/mm/hugetlbpage.c               | 10 -------
>   arch/mips/include/asm/pgtable-32.h            |  2 +-
>   arch/mips/include/asm/pgtable-64.h            |  2 +-
>   arch/mips/mm/hugetlbpage.c                    | 10 -------
>   arch/parisc/mm/hugetlbpage.c                  | 11 -------
>   .../include/asm/book3s/64/pgtable-4k.h        | 10 -------
>   .../include/asm/book3s/64/pgtable-64k.h       | 25 ----------------
>   arch/powerpc/include/asm/nohash/pgtable.h     | 10 -------
>   arch/riscv/mm/hugetlbpage.c                   | 10 -------
>   arch/s390/mm/hugetlbpage.c                    | 10 -------
>   arch/sh/mm/hugetlbpage.c                      | 10 -------
>   arch/sparc/mm/hugetlbpage.c                   | 10 -------
>   arch/x86/mm/hugetlbpage.c                     | 16 ----------
>   include/linux/hugetlb.h                       | 24 ---------------
>   17 files changed, 2 insertions(+), 198 deletions(-)
>   delete mode 100644 arch/arm/mm/hugetlbpage.c
> 

> diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h
> index 0e196650f4f4..92b7591aac2a 100644
> --- a/arch/mips/include/asm/pgtable-32.h
> +++ b/arch/mips/include/asm/pgtable-32.h
> @@ -129,7 +129,7 @@ static inline int pmd_none(pmd_t pmd)
>   static inline int pmd_bad(pmd_t pmd)
>   {
>   #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
> -	/* pmd_huge(pmd) but inline */
> +	/* pmd_leaf(pmd) but inline */

Shouldn't this comment have been changed in patch 11 ?

>   	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))

Unlike pmd_huge() which is an outline function, pmd_leaf() is a macro so 
it could be used here instead of open coping.

>   		return 0;
>   #endif
> diff --git a/arch/mips/include/asm/pgtable-64.h b/arch/mips/include/asm/pgtable-64.h
> index 20ca48c1b606..7c28510b3768 100644
> --- a/arch/mips/include/asm/pgtable-64.h
> +++ b/arch/mips/include/asm/pgtable-64.h
> @@ -245,7 +245,7 @@ static inline int pmd_none(pmd_t pmd)
>   static inline int pmd_bad(pmd_t pmd)
>   {
>   #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
> -	/* pmd_huge(pmd) but inline */
> +	/* pmd_leaf(pmd) but inline */

Same

>   	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))

Same

>   		return 0;
>   #endif

> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable-64k.h b/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
> index 2fce3498b000..579a7153857f 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
> @@ -4,31 +4,6 @@
>   
>   #ifndef __ASSEMBLY__
>   #ifdef CONFIG_HUGETLB_PAGE
> -/*
> - * We have PGD_INDEX_SIZ = 12 and PTE_INDEX_SIZE = 8, so that we can have
> - * 16GB hugepage pte in PGD and 16MB hugepage pte at PMD;
> - *
> - * Defined in such a way that we can optimize away code block at build time
> - * if CONFIG_HUGETLB_PAGE=n.
> - *
> - * returns true for pmd migration entries, THP, devmap, hugetlb
> - * But compile time dependent on CONFIG_HUGETLB_PAGE
> - */

Should we keep this comment somewhere for documentation ?

> -static inline int pmd_huge(pmd_t pmd)
> -{
> -	/*
> -	 * leaf pte for huge page
> -	 */
> -	return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE));
> -}
> -
> -static inline int pud_huge(pud_t pud)
> -{
> -	/*
> -	 * leaf pte for huge page
> -	 */
> -	return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE));
> -}
>   
>   /*
>    * With 64k page size, we have hugepage ptes in the pgd and pmd entries. We don't

On Thu, Mar 14, 2024 at 08:56:59AM +0000, Christophe Leroy wrote:
> 
> 
> Le 13/03/2024 à 22:47, peterx@redhat.com a écrit :
> > From: Peter Xu <peterx@redhat.com>
> > 
> > This API is not used anymore, drop it for the whole tree.
> > 
> > Signed-off-by: Peter Xu <peterx@redhat.com>
> > ---
> >   arch/arm/mm/Makefile                          |  1 -
> >   arch/arm/mm/hugetlbpage.c                     | 29 -------------------
> >   arch/arm64/mm/hugetlbpage.c                   | 10 -------
> >   arch/loongarch/mm/hugetlbpage.c               | 10 -------
> >   arch/mips/include/asm/pgtable-32.h            |  2 +-
> >   arch/mips/include/asm/pgtable-64.h            |  2 +-
> >   arch/mips/mm/hugetlbpage.c                    | 10 -------
> >   arch/parisc/mm/hugetlbpage.c                  | 11 -------
> >   .../include/asm/book3s/64/pgtable-4k.h        | 10 -------
> >   .../include/asm/book3s/64/pgtable-64k.h       | 25 ----------------
> >   arch/powerpc/include/asm/nohash/pgtable.h     | 10 -------
> >   arch/riscv/mm/hugetlbpage.c                   | 10 -------
> >   arch/s390/mm/hugetlbpage.c                    | 10 -------
> >   arch/sh/mm/hugetlbpage.c                      | 10 -------
> >   arch/sparc/mm/hugetlbpage.c                   | 10 -------
> >   arch/x86/mm/hugetlbpage.c                     | 16 ----------
> >   include/linux/hugetlb.h                       | 24 ---------------
> >   17 files changed, 2 insertions(+), 198 deletions(-)
> >   delete mode 100644 arch/arm/mm/hugetlbpage.c
> > 
> 
> > diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h
> > index 0e196650f4f4..92b7591aac2a 100644
> > --- a/arch/mips/include/asm/pgtable-32.h
> > +++ b/arch/mips/include/asm/pgtable-32.h
> > @@ -129,7 +129,7 @@ static inline int pmd_none(pmd_t pmd)
> >   static inline int pmd_bad(pmd_t pmd)
> >   {
> >   #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
> > -	/* pmd_huge(pmd) but inline */
> > +	/* pmd_leaf(pmd) but inline */
> 
> Shouldn't this comment have been changed in patch 11 ?

IMHO it's fine to be here, as this is the patch to finally drop _huge().
Patch 11 only converts the callers to use _leaf()s.  So this comment is
still valid until this patch, because this patch removes that definition.

> 
> >   	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
> 
> Unlike pmd_huge() which is an outline function, pmd_leaf() is a macro so 
> it could be used here instead of open coping.

I worry it will break things as pmd_leaf() can sometimes be defined after
arch *pgtable.h headers.  So I avoided touching it except what I think I'm
confident.  I had a feeling it's inlined just because of a similar reason
for the old _huge().

> 
> >   		return 0;
> >   #endif
> > diff --git a/arch/mips/include/asm/pgtable-64.h b/arch/mips/include/asm/pgtable-64.h
> > index 20ca48c1b606..7c28510b3768 100644
> > --- a/arch/mips/include/asm/pgtable-64.h
> > +++ b/arch/mips/include/asm/pgtable-64.h
> > @@ -245,7 +245,7 @@ static inline int pmd_none(pmd_t pmd)
> >   static inline int pmd_bad(pmd_t pmd)
> >   {
> >   #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
> > -	/* pmd_huge(pmd) but inline */
> > +	/* pmd_leaf(pmd) but inline */
> 
> Same
> 
> >   	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
> 
> Same
> 
> >   		return 0;
> >   #endif
> 
> > diff --git a/arch/powerpc/include/asm/book3s/64/pgtable-64k.h b/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
> > index 2fce3498b000..579a7153857f 100644
> > --- a/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
> > +++ b/arch/powerpc/include/asm/book3s/64/pgtable-64k.h
> > @@ -4,31 +4,6 @@
> >   
> >   #ifndef __ASSEMBLY__
> >   #ifdef CONFIG_HUGETLB_PAGE
> > -/*
> > - * We have PGD_INDEX_SIZ = 12 and PTE_INDEX_SIZE = 8, so that we can have
> > - * 16GB hugepage pte in PGD and 16MB hugepage pte at PMD;
> > - *
> > - * Defined in such a way that we can optimize away code block at build time
> > - * if CONFIG_HUGETLB_PAGE=n.
> > - *
> > - * returns true for pmd migration entries, THP, devmap, hugetlb
> > - * But compile time dependent on CONFIG_HUGETLB_PAGE
> > - */
> 
> Should we keep this comment somewhere for documentation ?

The 2nd/3rd paragraphs are definitely obsolete, so should be dropped.

OTOH, I'm not sure how much that will help if e.g. I move that over to
pmd_leaf(): a check over cpu_to_be64(_PAGE_PTE) is an implementation as
simple as it could be to explain itself with even no comment to me..

I also don't fully digest why that 1st paragraph discusses PGD entries: for
example, there's no pgd_huge() defined.  It may not mean that the comment
is wrong, perhaps it means that I may lack some knowledge around this area
on Power..

Would you suggest how I should move paragraph 1 (and help to explain what
it is describing)?  Or maybe we can provide a separate patch for Power's
huge page sizes but posted separately (and very possibly I'm not the best
candidate then..).

> 
> > -static inline int pmd_huge(pmd_t pmd)
> > -{
> > -	/*
> > -	 * leaf pte for huge page
> > -	 */
> > -	return !!(pmd_raw(pmd) & cpu_to_be64(_PAGE_PTE));
> > -}
> > -
> > -static inline int pud_huge(pud_t pud)
> > -{
> > -	/*
> > -	 * leaf pte for huge page
> > -	 */
> > -	return !!(pud_raw(pud) & cpu_to_be64(_PAGE_PTE));
> > -}
> >   
> >   /*
> >    * With 64k page size, we have hugepage ptes in the pgd and pmd entries. We don't

-- 
Peter Xu