[PATCH v2] Fix fake numa on ppc

Balbir Singh balbir at linux.vnet.ibm.com
Thu Sep 3 05:56:18 EST 2009


On Thu, Sep 3, 2009 at 1:06 AM, David Rientjes<rientjes at google.com> wrote:
> On Wed, 2 Sep 2009, Ankita Garg wrote:
>
>> Currently, the behavior of fake numa is not so on x86 as well? Below is
>> a sample output from a single node x86 system booted with numa=fake=8:
>>
>> # cat node0/cpulist
>>
>> # cat node1/cpulist
>>
>> ...
>> # cat node6/cpulist
>>
>> # cat node7/cpulist
>> 0-7
>>
>> Presently, just fixing the cpu association issue with ppc, as explained
>> in my previous mail.
>>
>
> Right, I'm proposing an alternate mapping scheme (which we've used for
> years) for both platforms such that a cpu is bound (and is set in
> cpumask_of_node()) to each fake node with which it has physical affinity.
> That is the only way for zonelist ordering in node order, task migration
> from offlined cpus, correct sched domains, etc.  I can propose a patchset
> for x86_64 to do exactly this if there aren't any objections and I hope
> you'll help do ppc.

Sounds interesting, I'd definitely be interested in seeing your
proposal, but I would think of that as additional development on top
of this patch

Balbir Singh.


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