2022-10-20 07:40:03

by Huacai Chen

Subject: [PATCH V12 4/4] LoongArch: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP

From: Feiyang Chen <[email protected]>

The feature of minimizing overhead of struct page associated with each
HugeTLB page is implemented on x86_64. However, the infrastructure of
this feature is already there, so just select ARCH_WANT_HUGETLB_PAGE_
OPTIMIZE_VMEMMAP is enough to enable this feature for LoongArch.

To avoid the following build error on LoongArch we should include linux/
static_key.h in page-flags.h.

In file included from ./include/linux/mmzone.h:22,
from ./include/linux/gfp.h:6,
from ./include/linux/mm.h:7,
from arch/loongarch/kernel/asm-offsets.c:9:
./include/linux/page-flags.h:208:1: warning: data definition has no
type or storage class
208 | DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
| ^~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/page-flags.h:208:1: error: type defaults to 'int' in
declaration of 'DECLARE_STATIC_KEY_MAYBE' [-Werror=implicit-int]
./include/linux/page-flags.h:209:26: warning: parameter names (without
types) in function declaration
209 | hugetlb_optimize_vmemmap_key);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/page-flags.h: In function 'hugetlb_optimize_vmemmap_enabled':
./include/linux/page-flags.h:213:16: error: implicit declaration of
function 'static_branch_maybe' [-Werror=implicit-function-declaration]
213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
| ^~~~~~~~~~~~~~~~~~~
./include/linux/page-flags.h:213:36: error:
'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON' undeclared (first
use in this function); did you mean
'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP'?
213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
./include/linux/page-flags.h:213:36: note: each undeclared identifier
is reported only once for each function it appears in
./include/linux/page-flags.h:214:37: error:
'hugetlb_optimize_vmemmap_key' undeclared (first use in this
function); did you mean 'hugetlb_optimize_vmemmap_enabled'?
214 | &hugetlb_optimize_vmemmap_key);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
| hugetlb_optimize_vmemmap_enabled

Signed-off-by: Feiyang Chen <[email protected]>
Signed-off-by: Huacai Chen <[email protected]>
---
arch/loongarch/Kconfig | 1 +
include/linux/page-flags.h | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 6f7fa0c0ca08..0a6ef613124c 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -52,6 +52,7 @@ config LOONGARCH
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
+ select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
select ARCH_WANT_LD_ORPHAN_WARN
select ARCH_WANTS_NO_INSTR
select BUILDTIME_TABLE_SORT
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 0b0ae5084e60..1aafdc73e399 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -9,6 +9,7 @@
#include <linux/types.h>
#include <linux/bug.h>
#include <linux/mmdebug.h>
+#include <linux/static_key.h>
#ifndef __GENERATING_BOUNDS_H
#include <linux/mm_types.h>
#include <generated/bounds.h>
--
2.31.1

2022-10-21 10:41:39

by Philippe Mathieu-Daudé

Subject: Re: [PATCH V12 4/4] LoongArch: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP

On 20/10/22 09:23, Huacai Chen wrote:
> From: Feiyang Chen <[email protected]>
>
> The feature of minimizing overhead of struct page associated with each
> HugeTLB page is implemented on x86_64. However, the infrastructure of
> this feature is already there, so just select ARCH_WANT_HUGETLB_PAGE_
> OPTIMIZE_VMEMMAP is enough to enable this feature for LoongArch.
>
> To avoid the following build error on LoongArch we should include linux/

s/should/have to/

> static_key.h in page-flags.h.

This looks like 2 different changes in a single patch.. The first is a
generic "fix missing include" and the second is LoongArch specific.

Splitting in 2 would ease backport cherry-picks.

> In file included from ./include/linux/mmzone.h:22,
> from ./include/linux/gfp.h:6,
> from ./include/linux/mm.h:7,
> from arch/loongarch/kernel/asm-offsets.c:9:
> ./include/linux/page-flags.h:208:1: warning: data definition has no
> type or storage class
> 208 | DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
> | ^~~~~~~~~~~~~~~~~~~~~~~~
> ./include/linux/page-flags.h:208:1: error: type defaults to 'int' in
> declaration of 'DECLARE_STATIC_KEY_MAYBE' [-Werror=implicit-int]
> ./include/linux/page-flags.h:209:26: warning: parameter names (without
> types) in function declaration
> 209 | hugetlb_optimize_vmemmap_key);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ./include/linux/page-flags.h: In function 'hugetlb_optimize_vmemmap_enabled':
> ./include/linux/page-flags.h:213:16: error: implicit declaration of
> function 'static_branch_maybe' [-Werror=implicit-function-declaration]
> 213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
> | ^~~~~~~~~~~~~~~~~~~
> ./include/linux/page-flags.h:213:36: error:
> 'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON' undeclared (first
> use in this function); did you mean
> 'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP'?
> 213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> | CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
> ./include/linux/page-flags.h:213:36: note: each undeclared identifier
> is reported only once for each function it appears in
> ./include/linux/page-flags.h:214:37: error:
> 'hugetlb_optimize_vmemmap_key' undeclared (first use in this
> function); did you mean 'hugetlb_optimize_vmemmap_enabled'?
> 214 | &hugetlb_optimize_vmemmap_key);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
> | hugetlb_optimize_vmemmap_enabled
>
> Signed-off-by: Feiyang Chen <[email protected]>
> Signed-off-by: Huacai Chen <[email protected]>
> ---
> arch/loongarch/Kconfig | 1 +
> include/linux/page-flags.h | 1 +
> 2 files changed, 2 insertions(+)
>
> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> index 6f7fa0c0ca08..0a6ef613124c 100644
> --- a/arch/loongarch/Kconfig
> +++ b/arch/loongarch/Kconfig
> @@ -52,6 +52,7 @@ config LOONGARCH
> select ARCH_USE_QUEUED_RWLOCKS
> select ARCH_USE_QUEUED_SPINLOCKS
> select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
> + select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
> select ARCH_WANT_LD_ORPHAN_WARN
> select ARCH_WANTS_NO_INSTR
> select BUILDTIME_TABLE_SORT
> diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
> index 0b0ae5084e60..1aafdc73e399 100644
> --- a/include/linux/page-flags.h
> +++ b/include/linux/page-flags.h
> @@ -9,6 +9,7 @@
> #include <linux/types.h>
> #include <linux/bug.h>
> #include <linux/mmdebug.h>
> +#include <linux/static_key.h>
> #ifndef __GENERATING_BOUNDS_H
> #include <linux/mm_types.h>
> #include <generated/bounds.h>

Preferably splitting in 2 distinct patches (for each):

Reviewed-by: Philippe Mathieu-Daudé <[email protected]>

2022-10-21 14:27:11

by Huacai Chen

Subject: Re: [PATCH V12 4/4] LoongArch: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP

Hi, Philippe,

On Fri, Oct 21, 2022 at 6:16 PM Philippe Mathieu-Daudé
<[email protected]> wrote:
>
> On 20/10/22 09:23, Huacai Chen wrote:
> > From: Feiyang Chen <[email protected]>
> >
> > The feature of minimizing overhead of struct page associated with each
> > HugeTLB page is implemented on x86_64. However, the infrastructure of
> > this feature is already there, so just select ARCH_WANT_HUGETLB_PAGE_
> > OPTIMIZE_VMEMMAP is enough to enable this feature for LoongArch.
> >
> > To avoid the following build error on LoongArch we should include linux/
>
> s/should/have to/
Thanks, I will change it.

>
> > static_key.h in page-flags.h.
>
> This looks like 2 different changes in a single patch.. The first is a
> generic "fix missing include" and the second is LoongArch specific.
The static_key.h inclusion is also LoongArch-specific, implicitly. X86
and ARM64 have no build errors without this inclusion, because they
include static_key.h from their arch-specific core headers. Once
before I have sent a separate patch to "fix missing include", but Greg
said that "don't fix unless you have a real problem". :)

Huacai

>
> Splitting in 2 would ease backport cherry-picks.
>
> > In file included from ./include/linux/mmzone.h:22,
> > from ./include/linux/gfp.h:6,
> > from ./include/linux/mm.h:7,
> > from arch/loongarch/kernel/asm-offsets.c:9:
> > ./include/linux/page-flags.h:208:1: warning: data definition has no
> > type or storage class
> > 208 | DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
> > | ^~~~~~~~~~~~~~~~~~~~~~~~
> > ./include/linux/page-flags.h:208:1: error: type defaults to 'int' in
> > declaration of 'DECLARE_STATIC_KEY_MAYBE' [-Werror=implicit-int]
> > ./include/linux/page-flags.h:209:26: warning: parameter names (without
> > types) in function declaration
> > 209 | hugetlb_optimize_vmemmap_key);
> > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > ./include/linux/page-flags.h: In function 'hugetlb_optimize_vmemmap_enabled':
> > ./include/linux/page-flags.h:213:16: error: implicit declaration of
> > function 'static_branch_maybe' [-Werror=implicit-function-declaration]
> > 213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
> > | ^~~~~~~~~~~~~~~~~~~
> > ./include/linux/page-flags.h:213:36: error:
> > 'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON' undeclared (first
> > use in this function); did you mean
> > 'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP'?
> > 213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
> > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > | CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
> > ./include/linux/page-flags.h:213:36: note: each undeclared identifier
> > is reported only once for each function it appears in
> > ./include/linux/page-flags.h:214:37: error:
> > 'hugetlb_optimize_vmemmap_key' undeclared (first use in this
> > function); did you mean 'hugetlb_optimize_vmemmap_enabled'?
> > 214 | &hugetlb_optimize_vmemmap_key);
> > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > | hugetlb_optimize_vmemmap_enabled
> >
> > Signed-off-by: Feiyang Chen <[email protected]>
> > Signed-off-by: Huacai Chen <[email protected]>
> > ---
> > arch/loongarch/Kconfig | 1 +
> > include/linux/page-flags.h | 1 +
> > 2 files changed, 2 insertions(+)
> >
> > diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> > index 6f7fa0c0ca08..0a6ef613124c 100644
> > --- a/arch/loongarch/Kconfig
> > +++ b/arch/loongarch/Kconfig
> > @@ -52,6 +52,7 @@ config LOONGARCH
> > select ARCH_USE_QUEUED_RWLOCKS
> > select ARCH_USE_QUEUED_SPINLOCKS
> > select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
> > + select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
> > select ARCH_WANT_LD_ORPHAN_WARN
> > select ARCH_WANTS_NO_INSTR
> > select BUILDTIME_TABLE_SORT
> > diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
> > index 0b0ae5084e60..1aafdc73e399 100644
> > --- a/include/linux/page-flags.h
> > +++ b/include/linux/page-flags.h
> > @@ -9,6 +9,7 @@
> > #include <linux/types.h>
> > #include <linux/bug.h>
> > #include <linux/mmdebug.h>
> > +#include <linux/static_key.h>
> > #ifndef __GENERATING_BOUNDS_H
> > #include <linux/mm_types.h>
> > #include <generated/bounds.h>
>
> Preferably splitting in 2 distinct patches (for each):
>
> Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
>
>