Subject: Re: [PATCH v4 4/5] mm: make processing of movable_node arch-specific

From: Balbir Singh <[email-masked]>
Date: Tue, 25 Oct 2016 23:15:40 +1100

On 11/10/16 23:26, Balbir Singh wrote:
> 
> 
> On 07/10/16 05:36, Reza Arbab wrote:
>> Currently, CONFIG_MOVABLE_NODE depends on X86_64. In preparation to
>> enable it for other arches, we need to factor a detail which is unique
>> to x86 out of the generic mm code.
>>
>> Specifically, as documented in kernel-parameters.txt, the use of
>> "movable_node" should remain restricted to x86:
>>
>> movable_node    [KNL,X86] Boot-time switch to enable the effects
>>                 of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details.
>>
>> This option tells x86 to find movable nodes identified by the ACPI SRAT.
>> On other arches, it would have no benefit, only the undesired side
>> effect of setting bottom-up memblock allocation.
>>
>> Since #ifdef CONFIG_MOVABLE_NODE will no longer be enough to restrict
>> this option to x86, move it to an arch-specific compilation unit
>> instead.
>>
>> Signed-off-by: Reza Arbab <[email-masked]>
> 
> Acked-by: Balbir Singh <[email-masked]>
> 

After the ack, I realized there were some more checks needed, IOW
questions for you :)

1. Have you checked to see if our memblock allocations spill
over to probably hotpluggable nodes?
2. Shouldn't we be marking nodes discovered as movable via
memblock_mark_hotplug()?

Balbir Singh.