[PATCH 0/5] Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA

[PATCH 0/5] Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA

[Hoan Tran OS]

This patch set enables CONFIG_NODES_SPAN_OTHER_NODES by default
for NUMA.

The original patch [1]
[1] arm64: Kconfig: Enable NODES_SPAN_OTHER_NODES config for NUMA
https://www.spinics.net/lists/arm-kernel/msg737306.html

Hoan Tran (5):
  mm: Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA
  powerpc: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES
  x86: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES
  sparc: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES
  s390: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

 arch/powerpc/Kconfig | 9 ---------
 arch/s390/Kconfig    | 8 --------
 arch/sparc/Kconfig   | 9 ---------
 arch/x86/Kconfig     | 9 ---------
 mm/page_alloc.c      | 2 +-
 5 files changed, 1 insertion(+), 36 deletions(-)

-- 
2.7.4

[PATCH 1/5] mm: Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA

[Hoan Tran OS]

This patch enables CONFIG_NODES_SPAN_OTHER_NODES by default
for NUMA. As some NUMA nodes have memory ranges that span other
nodes. Even though a pfn is valid and between a node's start and
end pfns, it may not reside on that node.

Signed-off-by: Hoan Tran <Hoan@os.amperecomputing.com>
---
 mm/page_alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d66bc8a..6335505 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1413,7 +1413,7 @@ int __meminit early_pfn_to_nid(unsigned long pfn)
 }
 #endif
 
-#ifdef CONFIG_NODES_SPAN_OTHER_NODES
+#ifdef CONFIG_NUMA
 /* Only safe to use early in boot when initialisation is single-threaded */
 static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
 {
-- 
2.7.4

[PATCH 2/5] powerpc: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Hoan Tran OS]

This patch removes CONFIG_NODES_SPAN_OTHER_NODES as it's
enabled by default with NUMA.

Signed-off-by: Hoan Tran <Hoan@os.amperecomputing.com>
---
 arch/powerpc/Kconfig | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 8c1c636..bdde8bc 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -629,15 +629,6 @@ config ARCH_MEMORY_PROBE
 	def_bool y
 	depends on MEMORY_HOTPLUG
 
-# Some NUMA nodes have memory ranges that span
-# other nodes.  Even though a pfn is valid and
-# between a node's start and end pfns, it may not
-# reside on that node.  See memmap_init_zone()
-# for details.
-config NODES_SPAN_OTHER_NODES
-	def_bool y
-	depends on NEED_MULTIPLE_NODES
-
 config STDBINUTILS
 	bool "Using standard binutils settings"
 	depends on 44x
-- 
2.7.4

[PATCH 3/5] x86: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Hoan Tran OS]

This patch removes CONFIG_NODES_SPAN_OTHER_NODES as it's
enabled by default with NUMA.

Signed-off-by: Hoan Tran <Hoan@os.amperecomputing.com>
---
 arch/x86/Kconfig | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2bbbd4d..fa9318c 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1567,15 +1567,6 @@ config X86_64_ACPI_NUMA
 	---help---
 	  Enable ACPI SRAT based node topology detection.
 
-# Some NUMA nodes have memory ranges that span
-# other nodes.  Even though a pfn is valid and
-# between a node's start and end pfns, it may not
-# reside on that node.  See memmap_init_zone()
-# for details.
-config NODES_SPAN_OTHER_NODES
-	def_bool y
-	depends on X86_64_ACPI_NUMA
-
 config NUMA_EMU
 	bool "NUMA emulation"
 	depends on NUMA
-- 
2.7.4

[PATCH 4/5] sparc: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Hoan Tran OS]

This patch removes CONFIG_NODES_SPAN_OTHER_NODES as it's
enabled by default with NUMA.

Signed-off-by: Hoan Tran <Hoan@os.amperecomputing.com>
---
 arch/sparc/Kconfig | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 26ab6f5..13449ea 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -291,15 +291,6 @@ config NODES_SHIFT
 	  Specify the maximum number of NUMA Nodes available on the target
 	  system.  Increases memory reserved to accommodate various tables.
 
-# Some NUMA nodes have memory ranges that span
-# other nodes.  Even though a pfn is valid and
-# between a node's start and end pfns, it may not
-# reside on that node.  See memmap_init_zone()
-# for details.
-config NODES_SPAN_OTHER_NODES
-	def_bool y
-	depends on NEED_MULTIPLE_NODES
-
 config ARCH_SELECT_MEMORY_MODEL
 	def_bool y if SPARC64
 
-- 
2.7.4

[PATCH 5/5] s390: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Hoan Tran OS]

This patch removes CONFIG_NODES_SPAN_OTHER_NODES as it's
enabled by default with NUMA.

Signed-off-by: Hoan Tran <Hoan@os.amperecomputing.com>
---
 arch/s390/Kconfig | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 109243f..788a8e9 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -438,14 +438,6 @@ config HOTPLUG_CPU
 	  can be controlled through /sys/devices/system/cpu/cpu#.
 	  Say N if you want to disable CPU hotplug.
 
-# Some NUMA nodes have memory ranges that span
-# other nodes.	Even though a pfn is valid and
-# between a node's start and end pfns, it may not
-# reside on that node.	See memmap_init_zone()
-# for details. <- They meant memory holes!
-config NODES_SPAN_OTHER_NODES
-	def_bool NUMA
-
 config NUMA
 	bool "NUMA support"
 	depends on SMP && SCHED_TOPOLOGY
-- 
2.7.4

Re: [PATCH 3/5] x86: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Thomas Gleixner]

Hoan,

On Tue, 25 Jun 2019, Hoan Tran OS wrote:

Please use 'x86/Kconfig: ' as prefix.

> This patch removes CONFIG_NODES_SPAN_OTHER_NODES as it's
> enabled by default with NUMA.

Please do not use 'This patch' in changelogs. It's pointless because we
already know that this is a patch.

See also Documentation/process/submitting-patches.rst and search for 'This
patch'

Simply say:

  Remove CONFIG_NODES_SPAN_OTHER_NODES as it's enabled by default with
  NUMA.

But .....

> @@ -1567,15 +1567,6 @@ config X86_64_ACPI_NUMA
>  	---help---
>  	  Enable ACPI SRAT based node topology detection.
>  
> -# Some NUMA nodes have memory ranges that span
> -# other nodes.  Even though a pfn is valid and
> -# between a node's start and end pfns, it may not
> -# reside on that node.  See memmap_init_zone()
> -# for details.
> -config NODES_SPAN_OTHER_NODES
> -	def_bool y
> -	depends on X86_64_ACPI_NUMA

the changelog does not mention that this lifts the dependency on
X86_64_ACPI_NUMA and therefore enables that functionality for anything
which has NUMA enabled including 32bit.

The core mm change gives no helpful information either. You just copied the
above comment text from some random Kconfig.

This needs a bit more data in the changelogs and the cover letter:

     - Why is it useful to enable it unconditionally

     - Why is it safe to do so, even if the architecture had constraints on
       it

     - What's the potential impact

Thanks,

	tglx

Re: [PATCH 0/5] Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA

[Linus Torvalds]

This is not a comment on the patch series itself, it is a comment on the emails.

Your email is mis-configured and ends up all being marked as spam for
me, because you go through the wrong smtp server (or maybe your smtp
server itself is miconfigured)

All your emails fail dmarc, because the "From" header is
os.amperecomputing.com, but the DKIM signature is for
amperemail.onmicrosoft.com.

End result: it wil all go into the spam box of anybody who checks DKIM.

                       Linus

On Wed, Jun 26, 2019 at 6:30 AM Hoan Tran OS
<hoan@os.amperecomputing.com> wrote:
>
> This patch set enables CONFIG_NODES_SPAN_OTHER_NODES by default
> for NUMA. [...]

Re: [PATCH 1/5] mm: Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA

[Michal Hocko]

On Tue 25-06-19 22:30:24, Hoan Tran OS wrote:
> This patch enables CONFIG_NODES_SPAN_OTHER_NODES by default
> for NUMA. As some NUMA nodes have memory ranges that span other
> nodes. Even though a pfn is valid and between a node's start and
> end pfns, it may not reside on that node.

Please describe the problem more thoroughly. What is the layout, what
doesn't work with the default configuration and why do we need this
particular fix rather than enabling of the config option for the
specific HW.

> 
> Signed-off-by: Hoan Tran <Hoan@os.amperecomputing.com>
> ---
>  mm/page_alloc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index d66bc8a..6335505 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -1413,7 +1413,7 @@ int __meminit early_pfn_to_nid(unsigned long pfn)
>  }
>  #endif
>  
> -#ifdef CONFIG_NODES_SPAN_OTHER_NODES
> +#ifdef CONFIG_NUMA
>  /* Only safe to use early in boot when initialisation is single-threaded */
>  static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
>  {
> -- 
> 2.7.4
> 

-- 
Michal Hocko
SUSE Labs

Re: [PATCH 0/5] Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA

[Aaron Lindsay OS]

On Jun 26 08:28, Linus Torvalds wrote:
> This is not a comment on the patch series itself, it is a comment on the emails.
> 
> Your email is mis-configured and ends up all being marked as spam for
> me, because you go through the wrong smtp server (or maybe your smtp
> server itself is miconfigured)
> 
> All your emails fail dmarc, because the "From" header is
> os.amperecomputing.com, but the DKIM signature is for
> amperemail.onmicrosoft.com.

It appears Microsoft enables DKIM by default, but does so using keys
advertised at *.onmicrosoft.com domains, and our IT folks didn't
initially notice this. We believe we've rectified the situation, so
please let us know if our emails (including this one) continue to be an
issue.

> End result: it wil all go into the spam box of anybody who checks DKIM.

Interestingly, *some* receiving mail servers (at least gmail.com) were
reporting DKIM/DMARC pass for emails sent directly from our domain
(though not those sent through a mailing list), which I believe allowed
our IT to falsely think they had everything configured correctly.

-Aaron

Re: [PATCH 3/5] x86: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Hoan Tran OS]

Hi Thomas,

Thanks for you comments

On 6/25/19 3:45 PM, Thomas Gleixner wrote:
> Hoan,
> 
> On Tue, 25 Jun 2019, Hoan Tran OS wrote:
> 
> Please use 'x86/Kconfig: ' as prefix.
> 
>> This patch removes CONFIG_NODES_SPAN_OTHER_NODES as it's
>> enabled by default with NUMA.
> 
> Please do not use 'This patch' in changelogs. It's pointless because we
> already know that this is a patch.
> 
> See also Documentation/process/submitting-patches.rst and search for 'This
> patch'
> 
> Simply say:
> 
>    Remove CONFIG_NODES_SPAN_OTHER_NODES as it's enabled by default with
>    NUMA.
> 

Got it, will fix

> But .....
> 
>> @@ -1567,15 +1567,6 @@ config X86_64_ACPI_NUMA
>>   	---help---
>>   	  Enable ACPI SRAT based node topology detection.
>>   
>> -# Some NUMA nodes have memory ranges that span
>> -# other nodes.  Even though a pfn is valid and
>> -# between a node's start and end pfns, it may not
>> -# reside on that node.  See memmap_init_zone()
>> -# for details.
>> -config NODES_SPAN_OTHER_NODES
>> -	def_bool y
>> -	depends on X86_64_ACPI_NUMA
> 
> the changelog does not mention that this lifts the dependency on
> X86_64_ACPI_NUMA and therefore enables that functionality for anything
> which has NUMA enabled including 32bit.
> 

I think this config is used for a NUMA layout which NUMA nodes addresses 
are spanned to other nodes. I think 32bit NUMA also have the same issue 
with that layout. Please correct me if I'm wrong.

> The core mm change gives no helpful information either. You just copied the
> above comment text from some random Kconfig.

Yes, as it's a correct comment and is used at multiple places.

Thanks
Hoan

> 
> This needs a bit more data in the changelogs and the cover letter:
> 
>       - Why is it useful to enable it unconditionally
> 
>       - Why is it safe to do so, even if the architecture had constraints on
>         it
> 
>       - What's the potential impact
> 
> Thanks,
> 
> 	tglx
> 

Re: [PATCH 3/5] x86: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Thomas Gleixner]

Hoan,

On Wed, 10 Jul 2019, Hoan Tran OS wrote:
> On 6/25/19 3:45 PM, Thomas Gleixner wrote:
> > On Tue, 25 Jun 2019, Hoan Tran OS wrote:
> >> @@ -1567,15 +1567,6 @@ config X86_64_ACPI_NUMA
> >>   	---help---
> >>   	  Enable ACPI SRAT based node topology detection.
> >>   
> >> -# Some NUMA nodes have memory ranges that span
> >> -# other nodes.  Even though a pfn is valid and
> >> -# between a node's start and end pfns, it may not
> >> -# reside on that node.  See memmap_init_zone()
> >> -# for details.
> >> -config NODES_SPAN_OTHER_NODES
> >> -	def_bool y
> >> -	depends on X86_64_ACPI_NUMA
> > 
> > the changelog does not mention that this lifts the dependency on
> > X86_64_ACPI_NUMA and therefore enables that functionality for anything
> > which has NUMA enabled including 32bit.
> > 
> 
> I think this config is used for a NUMA layout which NUMA nodes addresses 
> are spanned to other nodes. I think 32bit NUMA also have the same issue 
> with that layout. Please correct me if I'm wrong.

I'm not saying you're wrong, but it's your duty to provide the analysis why
this is correct for everything which has NUMA enabled.

> > The core mm change gives no helpful information either. You just copied the
> > above comment text from some random Kconfig.
> 
> Yes, as it's a correct comment and is used at multiple places.

Well it maybe correct in terms of explaining what this is about, it still
does not explain why this is needed by default on everything which has NUMA
enabled.

Thanks,

	tglx

Re: [PATCH 3/5] x86: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES

[Hoan Tran OS]

Hi Thomas,


On 7/10/19 12:58 PM, Thomas Gleixner wrote:
> Hoan,
> 
> On Wed, 10 Jul 2019, Hoan Tran OS wrote:
>> On 6/25/19 3:45 PM, Thomas Gleixner wrote:
>>> On Tue, 25 Jun 2019, Hoan Tran OS wrote:
>>>> @@ -1567,15 +1567,6 @@ config X86_64_ACPI_NUMA
>>>>    	---help---
>>>>    	  Enable ACPI SRAT based node topology detection.
>>>>    
>>>> -# Some NUMA nodes have memory ranges that span
>>>> -# other nodes.  Even though a pfn is valid and
>>>> -# between a node's start and end pfns, it may not
>>>> -# reside on that node.  See memmap_init_zone()
>>>> -# for details.
>>>> -config NODES_SPAN_OTHER_NODES
>>>> -	def_bool y
>>>> -	depends on X86_64_ACPI_NUMA
>>>
>>> the changelog does not mention that this lifts the dependency on
>>> X86_64_ACPI_NUMA and therefore enables that functionality for anything
>>> which has NUMA enabled including 32bit.
>>>
>>
>> I think this config is used for a NUMA layout which NUMA nodes addresses
>> are spanned to other nodes. I think 32bit NUMA also have the same issue
>> with that layout. Please correct me if I'm wrong.
> 
> I'm not saying you're wrong, but it's your duty to provide the analysis why
> this is correct for everything which has NUMA enabled.
> 
>>> The core mm change gives no helpful information either. You just copied the
>>> above comment text from some random Kconfig.
>>
>> Yes, as it's a correct comment and is used at multiple places.
> 
> Well it maybe correct in terms of explaining what this is about, it still
> does not explain why this is needed by default on everything which has NUMA
> enabled.

Let me send another patch with the detail explanation.

Thanks
Hoan

> 
> Thanks,
> 
> 	tglx
>