diff mbox series

[3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS

Message ID 1586864670-21799-4-git-send-email-anshuman.khandual@arm.com (mailing list archive)
State Awaiting Upstream
Headers show
Series mm/hugetlb: Add some new arch enabling macros | expand

Commit Message

Anshuman Khandual April 14, 2020, 11:44 a.m. UTC
There are multiple similar definitions for arch_clear_hugepage_flags() on
various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
platforms that need to define their own arch_clear_hugepage_flags() while
also providing a generic fallback definition for others to use. This help
reduce code duplication.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
 arch/arm/include/asm/hugetlb.h     | 1 +
 arch/arm64/include/asm/hugetlb.h   | 1 +
 arch/ia64/include/asm/hugetlb.h    | 4 ----
 arch/mips/include/asm/hugetlb.h    | 4 ----
 arch/parisc/include/asm/hugetlb.h  | 4 ----
 arch/powerpc/include/asm/hugetlb.h | 4 ----
 arch/riscv/include/asm/hugetlb.h   | 4 ----
 arch/s390/include/asm/hugetlb.h    | 1 +
 arch/sh/include/asm/hugetlb.h      | 1 +
 arch/sparc/include/asm/hugetlb.h   | 4 ----
 arch/x86/include/asm/hugetlb.h     | 4 ----
 include/linux/hugetlb.h            | 4 ++++
 12 files changed, 8 insertions(+), 28 deletions(-)

Comments

Andrew Morton April 26, 2020, 12:55 a.m. UTC | #1
On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:

> There are multiple similar definitions for arch_clear_hugepage_flags() on
> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
> platforms that need to define their own arch_clear_hugepage_flags() while
> also providing a generic fallback definition for others to use. This help
> reduce code duplication.
> 
> ...
>
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
>  }
>  #endif
>  
> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
> +static inline void arch_clear_hugepage_flags(struct page *page) { }
> +#endif
> +
>  #ifndef arch_make_huge_pte
>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
>  				       struct page *page, int writable)

This is the rather old-school way of doing it.  The Linus-suggested way is

#ifndef arch_clear_hugepage_flags
static inline void arch_clear_hugepage_flags(struct page *page)
{
}
#define arch_clear_hugepage_flags arch_clear_hugepage_flags
#endif

And the various arch headers do

static inline void arch_clear_hugepage_flags(struct page *page)
{
	<some implementation>
}
#define arch_clear_hugepage_flags arch_clear_hugepage_flags

It's a small difference - mainly to avoid adding two variables to the
overall namespace where one would do.
Anshuman Khandual April 26, 2020, 2:43 a.m. UTC | #2
On 04/26/2020 06:25 AM, Andrew Morton wrote:
> On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
> 
>> There are multiple similar definitions for arch_clear_hugepage_flags() on
>> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
>> platforms that need to define their own arch_clear_hugepage_flags() while
>> also providing a generic fallback definition for others to use. This help
>> reduce code duplication.
>>
>> ...
>>
>> --- a/include/linux/hugetlb.h
>> +++ b/include/linux/hugetlb.h
>> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
>>  }
>>  #endif
>>  
>> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
>> +static inline void arch_clear_hugepage_flags(struct page *page) { }
>> +#endif
>> +
>>  #ifndef arch_make_huge_pte
>>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
>>  				       struct page *page, int writable)
> 
> This is the rather old-school way of doing it.  The Linus-suggested way is
> 
> #ifndef arch_clear_hugepage_flags
> static inline void arch_clear_hugepage_flags(struct page *page)
> {
> }
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags

Do we need that above line here ? Is not that implicit.

> #endif
> 
> And the various arch headers do
> 
> static inline void arch_clear_hugepage_flags(struct page *page)
> {
> 	<some implementation>
> }
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> 
> It's a small difference - mainly to avoid adding two variables to the
> overall namespace where one would do.

Understood, will change and resend.

> 
>
Andrew Morton April 26, 2020, 3:01 a.m. UTC | #3
On Sun, 26 Apr 2020 08:13:17 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:

> 
> 
> On 04/26/2020 06:25 AM, Andrew Morton wrote:
> > On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
> > 
> >> There are multiple similar definitions for arch_clear_hugepage_flags() on
> >> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
> >> platforms that need to define their own arch_clear_hugepage_flags() while
> >> also providing a generic fallback definition for others to use. This help
> >> reduce code duplication.
> >>
> >> ...
> >>
> >> --- a/include/linux/hugetlb.h
> >> +++ b/include/linux/hugetlb.h
> >> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
> >>  }
> >>  #endif
> >>  
> >> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
> >> +static inline void arch_clear_hugepage_flags(struct page *page) { }
> >> +#endif
> >> +
> >>  #ifndef arch_make_huge_pte
> >>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
> >>  				       struct page *page, int writable)
> > 
> > This is the rather old-school way of doing it.  The Linus-suggested way is
> > 
> > #ifndef arch_clear_hugepage_flags
> > static inline void arch_clear_hugepage_flags(struct page *page)
> > {
> > }
> > #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> 
> Do we need that above line here ? Is not that implicit.

It depends if other header files want to test whether
arch_clear_hugepage_flags is already defined.  If the header heorarchy
is well-defined and working properly, they shouldn't need to, because
we're reliably indluding the relevant arch header before (or early
within) include/linux/hugetlb.h.

It would be nice if

#define arch_clear_hugepage_flags arch_clear_hugepage_flags
#define arch_clear_hugepage_flags arch_clear_hugepage_flags

were to generate an compiler error but it doesn't.  If it did we could
detect these incorrect inclusion orders.

> > #endif
> > 
> > And the various arch headers do
> > 
> > static inline void arch_clear_hugepage_flags(struct page *page)
> > {
> > 	<some implementation>
> > }
> > #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> > 
> > It's a small difference - mainly to avoid adding two variables to the
> > overall namespace where one would do.
> 
> Understood, will change and resend.

That's OK - I've queued up that fix.
Anshuman Khandual May 5, 2020, 2:51 a.m. UTC | #4
On 04/26/2020 08:31 AM, Andrew Morton wrote:
> On Sun, 26 Apr 2020 08:13:17 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
> 
>>
>>
>> On 04/26/2020 06:25 AM, Andrew Morton wrote:
>>> On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
>>>
>>>> There are multiple similar definitions for arch_clear_hugepage_flags() on
>>>> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
>>>> platforms that need to define their own arch_clear_hugepage_flags() while
>>>> also providing a generic fallback definition for others to use. This help
>>>> reduce code duplication.
>>>>
>>>> ...
>>>>
>>>> --- a/include/linux/hugetlb.h
>>>> +++ b/include/linux/hugetlb.h
>>>> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
>>>>  }
>>>>  #endif
>>>>  
>>>> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
>>>> +static inline void arch_clear_hugepage_flags(struct page *page) { }
>>>> +#endif
>>>> +
>>>>  #ifndef arch_make_huge_pte
>>>>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
>>>>  				       struct page *page, int writable)
>>>
>>> This is the rather old-school way of doing it.  The Linus-suggested way is
>>>
>>> #ifndef arch_clear_hugepage_flags
>>> static inline void arch_clear_hugepage_flags(struct page *page)
>>> {
>>> }
>>> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
>>
>> Do we need that above line here ? Is not that implicit.
> 
> It depends if other header files want to test whether
> arch_clear_hugepage_flags is already defined.  If the header heorarchy
> is well-defined and working properly, they shouldn't need to, because
> we're reliably indluding the relevant arch header before (or early
> within) include/linux/hugetlb.h.
> 
> It would be nice if
> 
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> 
> were to generate an compiler error but it doesn't.  If it did we could
> detect these incorrect inclusion orders.
> 
>>> #endif
>>>
>>> And the various arch headers do
>>>
>>> static inline void arch_clear_hugepage_flags(struct page *page)
>>> {
>>> 	<some implementation>
>>> }
>>> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
>>>
>>> It's a small difference - mainly to avoid adding two variables to the
>>> overall namespace where one would do.
>>
>> Understood, will change and resend.
> 
> That's OK - I've queued up that fix.
>

Hello Andrew,

I might not have searched all the relevant trees or might have just searched
earlier than required. But I dont see these patches (or your proposed fixes)
either in mmotm (2020-04-29-23-04) or in next-20200504. Wondering if you are
waiting on a V2 for this series accommodating the changes you had proposed.

- Anshuman
Andrew Morton May 5, 2020, 8:12 p.m. UTC | #5
On Tue, 5 May 2020 08:21:34 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:

> >>> static inline void arch_clear_hugepage_flags(struct page *page)
> >>> {
> >>> 	<some implementation>
> >>> }
> >>> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> >>>
> >>> It's a small difference - mainly to avoid adding two variables to the
> >>> overall namespace where one would do.
> >>
> >> Understood, will change and resend.
> > 
> > That's OK - I've queued up that fix.
> >
> 
> Hello Andrew,
> 
> I might not have searched all the relevant trees or might have just searched
> earlier than required. But I dont see these patches (or your proposed fixes)
> either in mmotm (2020-04-29-23-04) or in next-20200504. Wondering if you are
> waiting on a V2 for this series accommodating the changes you had proposed.

hm.  I think I must have got confused and thought you were referring to
a different patch.  Yes please, let's have v2.
diff mbox series

Patch

diff --git a/arch/arm/include/asm/hugetlb.h b/arch/arm/include/asm/hugetlb.h
index 9ecd516d1ff7..7107c1e6f020 100644
--- a/arch/arm/include/asm/hugetlb.h
+++ b/arch/arm/include/asm/hugetlb.h
@@ -14,6 +14,7 @@ 
 #include <asm/hugetlb-3level.h>
 #include <asm-generic/hugetlb.h>
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index 8f58e052697a..5369cf26a05d 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -17,6 +17,7 @@ 
 extern bool arch_hugetlb_migration_supported(struct hstate *h);
 #endif
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/ia64/include/asm/hugetlb.h b/arch/ia64/include/asm/hugetlb.h
index f17c1e228045..2ecff18a32e5 100644
--- a/arch/ia64/include/asm/hugetlb.h
+++ b/arch/ia64/include/asm/hugetlb.h
@@ -28,10 +28,6 @@  static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
 {
 }
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #endif /* _ASM_IA64_HUGETLB_H */
diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h
index 8b201e281f67..10e3be870df7 100644
--- a/arch/mips/include/asm/hugetlb.h
+++ b/arch/mips/include/asm/hugetlb.h
@@ -75,10 +75,6 @@  static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 	return changed;
 }
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #endif /* __ASM_HUGETLB_H */
diff --git a/arch/parisc/include/asm/hugetlb.h b/arch/parisc/include/asm/hugetlb.h
index 411d9d867baa..a69cf9efb0c1 100644
--- a/arch/parisc/include/asm/hugetlb.h
+++ b/arch/parisc/include/asm/hugetlb.h
@@ -42,10 +42,6 @@  int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 					     unsigned long addr, pte_t *ptep,
 					     pte_t pte, int dirty);
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #endif /* _ASM_PARISC64_HUGETLB_H */
diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h
index 9dd50e1e4fe5..d259e056e6cf 100644
--- a/arch/powerpc/include/asm/hugetlb.h
+++ b/arch/powerpc/include/asm/hugetlb.h
@@ -61,10 +61,6 @@  int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 			       unsigned long addr, pte_t *ptep,
 			       pte_t pte, int dirty);
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #else /* ! CONFIG_HUGETLB_PAGE */
diff --git a/arch/riscv/include/asm/hugetlb.h b/arch/riscv/include/asm/hugetlb.h
index 866f6ae6467c..a5c2ca1d1cd8 100644
--- a/arch/riscv/include/asm/hugetlb.h
+++ b/arch/riscv/include/asm/hugetlb.h
@@ -5,8 +5,4 @@ 
 #include <asm-generic/hugetlb.h>
 #include <asm/page.h>
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #endif /* _ASM_RISCV_HUGETLB_H */
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 7d27ea96ec2f..9f067a66609b 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -35,6 +35,7 @@  static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_arch_1, &page->flags);
diff --git a/arch/sh/include/asm/hugetlb.h b/arch/sh/include/asm/hugetlb.h
index 536ad2cb8aa4..869b5a947f07 100644
--- a/arch/sh/include/asm/hugetlb.h
+++ b/arch/sh/include/asm/hugetlb.h
@@ -26,6 +26,7 @@  static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
 {
 }
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/sparc/include/asm/hugetlb.h b/arch/sparc/include/asm/hugetlb.h
index a056fe1119f5..53838a173f62 100644
--- a/arch/sparc/include/asm/hugetlb.h
+++ b/arch/sparc/include/asm/hugetlb.h
@@ -47,10 +47,6 @@  static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 	return changed;
 }
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #define __HAVE_ARCH_HUGETLB_FREE_PGD_RANGE
 void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
 			    unsigned long end, unsigned long floor,
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index cc98f79074d0..1721b1aadeb1 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -7,8 +7,4 @@ 
 
 #define hugepages_supported() boot_cpu_has(X86_FEATURE_PSE)
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #endif /* _ASM_X86_HUGETLB_H */
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 2342e5a8d1dd..359cfa1b6f54 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -544,6 +544,10 @@  static inline int is_hugepage_only_range(struct mm_struct *mm,
 }
 #endif
 
+#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
+static inline void arch_clear_hugepage_flags(struct page *page) { }
+#endif
+
 #ifndef arch_make_huge_pte
 static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
 				       struct page *page, int writable)