diff mbox series

[v4,1/2] mm: hugetlb_vmemmap: introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP

Message ID 20220331065640.5777-1-songmuchun@bytedance.com (mailing list archive)
State New, archived
Headers show
Series [v4,1/2] mm: hugetlb_vmemmap: introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP | expand

Commit Message

Muchun Song March 31, 2022, 6:56 a.m. UTC
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, we could easily enable it for other
architectures.  Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other
architectures to be easily enabled.  Just select this config if they
want to enable this feature.

Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
 arch/x86/Kconfig |  1 +
 fs/Kconfig       | 10 +++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

Comments

David Hildenbrand March 31, 2022, 8:42 a.m. UTC | #1
On 31.03.22 08:56, Muchun Song wrote:
> 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, we could easily enable it for other
> architectures.  Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other
> architectures to be easily enabled.  Just select this config if they
> want to enable this feature.
> 
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> ---
>  arch/x86/Kconfig |  1 +
>  fs/Kconfig       | 10 +++++++++-
>  2 files changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 9f5bd41bf660..e69d42528542 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -119,6 +119,7 @@ config X86
>  	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
>  	select ARCH_WANTS_NO_INSTR
>  	select ARCH_WANT_HUGE_PMD_SHARE
> +	select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP	if X86_64
>  	select ARCH_WANT_LD_ORPHAN_WARN
>  	select ARCH_WANTS_THP_SWAP		if X86_64
>  	select ARCH_HAS_PARANOID_L1D_FLUSH
> diff --git a/fs/Kconfig b/fs/Kconfig
> index 6c7dc1387beb..f6db2af33738 100644
> --- a/fs/Kconfig
> +++ b/fs/Kconfig
> @@ -245,9 +245,17 @@ config HUGETLBFS
>  config HUGETLB_PAGE
>  	def_bool HUGETLBFS
>  
> +#
> +# Select this config option from the architecture Kconfig, if it is preferred
> +# to enable the feature of minimizing overhead of struct page associated with
> +# each HugeTLB page.
> +#
> +config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
> +	bool
> +
>  config HUGETLB_PAGE_FREE_VMEMMAP
>  	def_bool HUGETLB_PAGE
> -	depends on X86_64
> +	depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
>  	depends on SPARSEMEM_VMEMMAP
>  
>  config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON


I think something like "HUGETLB_OPTIMIZE_VMEMMAP" might be more
expressive, but that would imply renaming the existing config knob.

Apart from that LGTM.
Muchun Song March 31, 2022, 8:48 a.m. UTC | #2
On Thu, Mar 31, 2022 at 4:42 PM David Hildenbrand <david@redhat.com> wrote:
>
> On 31.03.22 08:56, Muchun Song wrote:
> > 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, we could easily enable it for other
> > architectures.  Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other
> > architectures to be easily enabled.  Just select this config if they
> > want to enable this feature.
> >
> > Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> > Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> > ---
> >  arch/x86/Kconfig |  1 +
> >  fs/Kconfig       | 10 +++++++++-
> >  2 files changed, 10 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > index 9f5bd41bf660..e69d42528542 100644
> > --- a/arch/x86/Kconfig
> > +++ b/arch/x86/Kconfig
> > @@ -119,6 +119,7 @@ config X86
> >       select ARCH_WANTS_DYNAMIC_TASK_STRUCT
> >       select ARCH_WANTS_NO_INSTR
> >       select ARCH_WANT_HUGE_PMD_SHARE
> > +     select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP      if X86_64
> >       select ARCH_WANT_LD_ORPHAN_WARN
> >       select ARCH_WANTS_THP_SWAP              if X86_64
> >       select ARCH_HAS_PARANOID_L1D_FLUSH
> > diff --git a/fs/Kconfig b/fs/Kconfig
> > index 6c7dc1387beb..f6db2af33738 100644
> > --- a/fs/Kconfig
> > +++ b/fs/Kconfig
> > @@ -245,9 +245,17 @@ config HUGETLBFS
> >  config HUGETLB_PAGE
> >       def_bool HUGETLBFS
> >
> > +#
> > +# Select this config option from the architecture Kconfig, if it is preferred
> > +# to enable the feature of minimizing overhead of struct page associated with
> > +# each HugeTLB page.
> > +#
> > +config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
> > +     bool
> > +
> >  config HUGETLB_PAGE_FREE_VMEMMAP
> >       def_bool HUGETLB_PAGE
> > -     depends on X86_64
> > +     depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
> >       depends on SPARSEMEM_VMEMMAP
> >
> >  config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON
>
>
> I think something like "HUGETLB_OPTIMIZE_VMEMMAP" might be more
> expressive, but that would imply renaming the existing config knob.
>

How about doing a full code cleanup in a separate series in the future?
David Hildenbrand March 31, 2022, 8:50 a.m. UTC | #3
On 31.03.22 10:48, Muchun Song wrote:
> On Thu, Mar 31, 2022 at 4:42 PM David Hildenbrand <david@redhat.com> wrote:
>>
>> On 31.03.22 08:56, Muchun Song wrote:
>>> 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, we could easily enable it for other
>>> architectures.  Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other
>>> architectures to be easily enabled.  Just select this config if they
>>> want to enable this feature.
>>>
>>> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
>>> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
>>> ---
>>>  arch/x86/Kconfig |  1 +
>>>  fs/Kconfig       | 10 +++++++++-
>>>  2 files changed, 10 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
>>> index 9f5bd41bf660..e69d42528542 100644
>>> --- a/arch/x86/Kconfig
>>> +++ b/arch/x86/Kconfig
>>> @@ -119,6 +119,7 @@ config X86
>>>       select ARCH_WANTS_DYNAMIC_TASK_STRUCT
>>>       select ARCH_WANTS_NO_INSTR
>>>       select ARCH_WANT_HUGE_PMD_SHARE
>>> +     select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP      if X86_64
>>>       select ARCH_WANT_LD_ORPHAN_WARN
>>>       select ARCH_WANTS_THP_SWAP              if X86_64
>>>       select ARCH_HAS_PARANOID_L1D_FLUSH
>>> diff --git a/fs/Kconfig b/fs/Kconfig
>>> index 6c7dc1387beb..f6db2af33738 100644
>>> --- a/fs/Kconfig
>>> +++ b/fs/Kconfig
>>> @@ -245,9 +245,17 @@ config HUGETLBFS
>>>  config HUGETLB_PAGE
>>>       def_bool HUGETLBFS
>>>
>>> +#
>>> +# Select this config option from the architecture Kconfig, if it is preferred
>>> +# to enable the feature of minimizing overhead of struct page associated with
>>> +# each HugeTLB page.
>>> +#
>>> +config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
>>> +     bool
>>> +
>>>  config HUGETLB_PAGE_FREE_VMEMMAP
>>>       def_bool HUGETLB_PAGE
>>> -     depends on X86_64
>>> +     depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
>>>       depends on SPARSEMEM_VMEMMAP
>>>
>>>  config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON
>>
>>
>> I think something like "HUGETLB_OPTIMIZE_VMEMMAP" might be more
>> expressive, but that would imply renaming the existing config knob.
>>
> 
> How about doing a full code cleanup in a separate series in the future?
> 

Yeah.
Muchun Song March 31, 2022, 8:53 a.m. UTC | #4
On Thu, Mar 31, 2022 at 4:51 PM David Hildenbrand <david@redhat.com> wrote:
>
> On 31.03.22 10:48, Muchun Song wrote:
> > On Thu, Mar 31, 2022 at 4:42 PM David Hildenbrand <david@redhat.com> wrote:
> >>
> >> On 31.03.22 08:56, Muchun Song wrote:
> >>> 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, we could easily enable it for other
> >>> architectures.  Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other
> >>> architectures to be easily enabled.  Just select this config if they
> >>> want to enable this feature.
> >>>
> >>> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> >>> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> >>> ---
> >>>  arch/x86/Kconfig |  1 +
> >>>  fs/Kconfig       | 10 +++++++++-
> >>>  2 files changed, 10 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> >>> index 9f5bd41bf660..e69d42528542 100644
> >>> --- a/arch/x86/Kconfig
> >>> +++ b/arch/x86/Kconfig
> >>> @@ -119,6 +119,7 @@ config X86
> >>>       select ARCH_WANTS_DYNAMIC_TASK_STRUCT
> >>>       select ARCH_WANTS_NO_INSTR
> >>>       select ARCH_WANT_HUGE_PMD_SHARE
> >>> +     select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP      if X86_64
> >>>       select ARCH_WANT_LD_ORPHAN_WARN
> >>>       select ARCH_WANTS_THP_SWAP              if X86_64
> >>>       select ARCH_HAS_PARANOID_L1D_FLUSH
> >>> diff --git a/fs/Kconfig b/fs/Kconfig
> >>> index 6c7dc1387beb..f6db2af33738 100644
> >>> --- a/fs/Kconfig
> >>> +++ b/fs/Kconfig
> >>> @@ -245,9 +245,17 @@ config HUGETLBFS
> >>>  config HUGETLB_PAGE
> >>>       def_bool HUGETLBFS
> >>>
> >>> +#
> >>> +# Select this config option from the architecture Kconfig, if it is preferred
> >>> +# to enable the feature of minimizing overhead of struct page associated with
> >>> +# each HugeTLB page.
> >>> +#
> >>> +config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
> >>> +     bool
> >>> +
> >>>  config HUGETLB_PAGE_FREE_VMEMMAP
> >>>       def_bool HUGETLB_PAGE
> >>> -     depends on X86_64
> >>> +     depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
> >>>       depends on SPARSEMEM_VMEMMAP
> >>>
> >>>  config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON
> >>
> >>
> >> I think something like "HUGETLB_OPTIMIZE_VMEMMAP" might be more
> >> expressive, but that would imply renaming the existing config knob.
> >>
> >
> > How about doing a full code cleanup in a separate series in the future?
> >
>
> Yeah.
>

OK. Have Added it into my To-do list.

Thanks.
Barry Song March 31, 2022, 10:19 p.m. UTC | #5
On Thu, Mar 31, 2022 at 7:57 PM Muchun Song <songmuchun@bytedance.com> wrote:
>
> 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, we could easily enable it for other
> architectures.  Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other
> architectures to be easily enabled.  Just select this config if they
> want to enable this feature.
>
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>

Review-by: Barry Song <baohua@kernel.org>

> ---
>  arch/x86/Kconfig |  1 +
>  fs/Kconfig       | 10 +++++++++-
>  2 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 9f5bd41bf660..e69d42528542 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -119,6 +119,7 @@ config X86
>         select ARCH_WANTS_DYNAMIC_TASK_STRUCT
>         select ARCH_WANTS_NO_INSTR
>         select ARCH_WANT_HUGE_PMD_SHARE
> +       select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP      if X86_64
>         select ARCH_WANT_LD_ORPHAN_WARN
>         select ARCH_WANTS_THP_SWAP              if X86_64
>         select ARCH_HAS_PARANOID_L1D_FLUSH
> diff --git a/fs/Kconfig b/fs/Kconfig
> index 6c7dc1387beb..f6db2af33738 100644
> --- a/fs/Kconfig
> +++ b/fs/Kconfig
> @@ -245,9 +245,17 @@ config HUGETLBFS
>  config HUGETLB_PAGE
>         def_bool HUGETLBFS
>
> +#
> +# Select this config option from the architecture Kconfig, if it is preferred
> +# to enable the feature of minimizing overhead of struct page associated with
> +# each HugeTLB page.
> +#
> +config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
> +       bool
> +
>  config HUGETLB_PAGE_FREE_VMEMMAP
>         def_bool HUGETLB_PAGE
> -       depends on X86_64
> +       depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
>         depends on SPARSEMEM_VMEMMAP
>
>  config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON
> --
> 2.11.0
>
Anshuman Khandual April 4, 2022, 9:05 a.m. UTC | #6
On 3/31/22 12:26, Muchun Song wrote:
> 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, we could easily enable it for other
> architectures.  Introduce ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP for other
> architectures to be easily enabled.  Just select this config if they
> want to enable this feature.
> 
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> ---
>  arch/x86/Kconfig |  1 +
>  fs/Kconfig       | 10 +++++++++-
>  2 files changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 9f5bd41bf660..e69d42528542 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -119,6 +119,7 @@ config X86
>  	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
>  	select ARCH_WANTS_NO_INSTR
>  	select ARCH_WANT_HUGE_PMD_SHARE
> +	select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP	if X86_64
>  	select ARCH_WANT_LD_ORPHAN_WARN
>  	select ARCH_WANTS_THP_SWAP		if X86_64
>  	select ARCH_HAS_PARANOID_L1D_FLUSH
> diff --git a/fs/Kconfig b/fs/Kconfig
> index 6c7dc1387beb..f6db2af33738 100644
> --- a/fs/Kconfig
> +++ b/fs/Kconfig
> @@ -245,9 +245,17 @@ config HUGETLBFS
>  config HUGETLB_PAGE
>  	def_bool HUGETLBFS
>  
> +#
> +# Select this config option from the architecture Kconfig, if it is preferred
> +# to enable the feature of minimizing overhead of struct page associated with
> +# each HugeTLB page.
> +#
> +config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
> +	bool
> +
>  config HUGETLB_PAGE_FREE_VMEMMAP
>  	def_bool HUGETLB_PAGE
> -	depends on X86_64
> +	depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
>  	depends on SPARSEMEM_VMEMMAP
>  
>  config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON

Better to have platforms subscribe via ARCH_HAS/WANTS_ method instead
of direct dependency in the config itself.

LGTM.

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
diff mbox series

Patch

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 9f5bd41bf660..e69d42528542 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -119,6 +119,7 @@  config X86
 	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
 	select ARCH_WANTS_NO_INSTR
 	select ARCH_WANT_HUGE_PMD_SHARE
+	select ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP	if X86_64
 	select ARCH_WANT_LD_ORPHAN_WARN
 	select ARCH_WANTS_THP_SWAP		if X86_64
 	select ARCH_HAS_PARANOID_L1D_FLUSH
diff --git a/fs/Kconfig b/fs/Kconfig
index 6c7dc1387beb..f6db2af33738 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -245,9 +245,17 @@  config HUGETLBFS
 config HUGETLB_PAGE
 	def_bool HUGETLBFS
 
+#
+# Select this config option from the architecture Kconfig, if it is preferred
+# to enable the feature of minimizing overhead of struct page associated with
+# each HugeTLB page.
+#
+config ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
+	bool
+
 config HUGETLB_PAGE_FREE_VMEMMAP
 	def_bool HUGETLB_PAGE
-	depends on X86_64
+	depends on ARCH_WANT_HUGETLB_PAGE_FREE_VMEMMAP
 	depends on SPARSEMEM_VMEMMAP
 
 config HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON