[patch] x86: increase CONFIG_NODES_SHIFT max to 10

[patch] x86: increase CONFIG_NODES_SHIFT max to 10

[David Rientjes]

Some larger systems require more than 512 nodes, so increase the maximum
CONFIG_NODES_SHIFT to 10 for a new max of 1024 nodes.

This was tested with numa=fake=64M on systems with more than 64GB of RAM.
A total of 1022 nodes were initialized.

Successfully builds with no additional warnings on x86_64 allyesconfig.

Signed-off-by: David Rientjes <rientjes@google.com>
---
 Greg KH has queued up numa-fix-BUILD_BUG_ON-for-node_read_distance.patch
 for 2.6.35 to fix the build error when CONFIG_NODES_SHIFT is set to 10.
 See http://lkml.org/lkml/2010/3/10/390

 arch/x86/Kconfig |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1213,8 +1213,8 @@ config NUMA_EMU
 
 config NODES_SHIFT
 	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
-	range 1 9
-	default "9" if MAXSMP
+	range 1 10
+	default "10" if MAXSMP
 	default "6" if X86_64
 	default "4" if X86_NUMAQ
 	default "3"

Re: [patch] x86: increase CONFIG_NODES_SHIFT max to 10

[Ingo Molnar]

* David Rientjes <rientjes@google.com> wrote:

> Some larger systems require more than 512 nodes, so increase the maximum 
> CONFIG_NODES_SHIFT to 10 for a new max of 1024 nodes.
> 
> This was tested with numa=fake=64M on systems with more than 64GB of RAM. A 
> total of 1022 nodes were initialized.
> 
> Successfully builds with no additional warnings on x86_64 allyesconfig.

Not so here:

drivers/base/node.c:169: error: negative width in bit-field ?<anonymous>?

>  Greg KH has queued up numa-fix-BUILD_BUG_ON-for-node_read_distance.patch
>  for 2.6.35 to fix the build error when CONFIG_NODES_SHIFT is set to 10.
>  See http://lkml.org/lkml/2010/3/10/390

erm. Alas I cannot merge it in the x86 tree without that fix being upstream. 
Why for v2.6.35 - shouldnt that be v2.6.34?

	Ingo

Re: [patch] x86: increase CONFIG_NODES_SHIFT max to 10

[Greg KH]

On Thu, Mar 11, 2010 at 02:23:54PM +0100, Ingo Molnar wrote:
> 
> * David Rientjes <rientjes@google.com> wrote:
> 
> > Some larger systems require more than 512 nodes, so increase the maximum 
> > CONFIG_NODES_SHIFT to 10 for a new max of 1024 nodes.
> > 
> > This was tested with numa=fake=64M on systems with more than 64GB of RAM. A 
> > total of 1022 nodes were initialized.
> > 
> > Successfully builds with no additional warnings on x86_64 allyesconfig.
> 
> Not so here:
> 
> drivers/base/node.c:169: error: negative width in bit-field ?<anonymous>?
> 
> >  Greg KH has queued up numa-fix-BUILD_BUG_ON-for-node_read_distance.patch
> >  for 2.6.35 to fix the build error when CONFIG_NODES_SHIFT is set to 10.
> >  See http://lkml.org/lkml/2010/3/10/390

Well, it will be a few days before I queue it up...

> erm. Alas I cannot merge it in the x86 tree without that fix being upstream. 
> Why for v2.6.35 - shouldnt that be v2.6.34?

If it needs to go in before .35, or it should go through Ingo's trees, I
have no objection.

thanks,

greg k-h

Re: [patch] x86: increase CONFIG_NODES_SHIFT max to 10

[Ingo Molnar]

* Greg KH <gregkh@suse.de> wrote:

> > erm. Alas I cannot merge it in the x86 tree without that fix being 
> > upstream. Why for v2.6.35 - shouldnt that be v2.6.34?
> 
> If it needs to go in before .35, or it should go through Ingo's trees, I 
> have no objection.

It does not 'need' to be in .34 but if the fix is trivial enough then you 
could give it a try?

	Ingo

Re: [patch] x86: increase CONFIG_NODES_SHIFT max to 10

[Greg KH]

On Thu, Mar 11, 2010 at 03:15:33PM +0100, Ingo Molnar wrote:
> 
> * Greg KH <gregkh@suse.de> wrote:
> 
> > > erm. Alas I cannot merge it in the x86 tree without that fix being 
> > > upstream. Why for v2.6.35 - shouldnt that be v2.6.34?
> > 
> > If it needs to go in before .35, or it should go through Ingo's trees, I 
> > have no objection.
> 
> It does not 'need' to be in .34 but if the fix is trivial enough then you 
> could give it a try?

The fix is trivial, I'll queue it up.

thanks,

greg k-h

Re: [patch] x86: increase CONFIG_NODES_SHIFT max to 10

[Ingo Molnar]

* Greg KH <gregkh@suse.de> wrote:

> On Thu, Mar 11, 2010 at 03:15:33PM +0100, Ingo Molnar wrote:
> > 
> > * Greg KH <gregkh@suse.de> wrote:
> > 
> > > > erm. Alas I cannot merge it in the x86 tree without that fix being 
> > > > upstream. Why for v2.6.35 - shouldnt that be v2.6.34?
> > > 
> > > If it needs to go in before .35, or it should go through Ingo's trees, I 
> > > have no objection.
> > 
> > It does not 'need' to be in .34 but if the fix is trivial enough then you 
> > could give it a try?
> 
> The fix is trivial, I'll queue it up.

Thanks Greg!

	Ingo

[patch v2] x86: increase CONFIG_NODES_SHIFT max to 10

[David Rientjes]

Some larger systems require more than 512 nodes, so increase the maximum
CONFIG_NODES_SHIFT to 10 for a new max of 1024 nodes.

This was tested with numa=fake=64M on systems with more than 64GB of RAM.
A total of 1022 nodes were initialized.

Successfully builds with no additional warnings on x86_64 allyesconfig.

Signed-off-by: David Rientjes <rientjes@google.com>
---
 The BUILD_BUG_ON() in drivers/base/node.c has been fixed in Linus' -git
 (see 12ee3c0), so CONFIG_NODES_SHIFT of 10 no longer fails to compile for
 x86_64 allyesconfig.

 arch/x86/Kconfig |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1213,8 +1213,8 @@ config NUMA_EMU
 
 config NODES_SHIFT
 	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
-	range 1 9
-	default "9" if MAXSMP
+	range 1 10
+	default "10" if MAXSMP
 	default "6" if X86_64
 	default "4" if X86_NUMAQ
 	default "3"

[tip:x86/urgent] x86: Increase CONFIG_NODES_SHIFT max to 10

[tip-bot for David Rientjes]

Commit-ID:  51591e31dcb3716f03f962e26ec36a029aa46340
Gitweb:     http://git.kernel.org/tip/51591e31dcb3716f03f962e26ec36a029aa46340
Author:     David Rientjes <rientjes@google.com>
AuthorDate: Thu, 25 Mar 2010 15:39:27 -0700
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 2 Apr 2010 19:09:31 +0200

x86: Increase CONFIG_NODES_SHIFT max to 10

Some larger systems require more than 512 nodes, so increase the
maximum CONFIG_NODES_SHIFT to 10 for a new max of 1024 nodes.

This was tested with numa=fake=64M on systems with more than
64GB of RAM. A total of 1022 nodes were initialized.

Successfully builds with no additional warnings on x86_64
allyesconfig.

( No effect on any existing config. Newly enabled CONFIG_MAXSMP=y
  will see the new default. )

Signed-off-by: David Rientjes <rientjes@google.com>
LKML-Reference: <alpine.DEB.2.00.1003251538060.8589@chino.kir.corp.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/Kconfig |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0eacb1f..9458685 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1216,8 +1216,8 @@ config NUMA_EMU
 
 config NODES_SHIFT
 	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
-	range 1 9
-	default "9" if MAXSMP
+	range 1 10
+	default "10" if MAXSMP
 	default "6" if X86_64
 	default "4" if X86_NUMAQ
 	default "3"