Re: [PATCH] x86/numa: move setting parse numa node to num_add_memblk

From: zhong jiang
Date: Wed Nov 29 2017 - 08:47:28 EST


On 2017/11/29 21:33, Michal Hocko wrote:
> On Wed 29-11-17 21:26:19, zhong jiang wrote:
>> On 2017/11/29 21:01, Michal Hocko wrote:
>>> On Wed 29-11-17 20:41:25, zhong jiang wrote:
>>>> On 2017/11/29 20:03, Michal Hocko wrote:
>>>>> On Wed 29-11-17 17:13:27, zhong jiang wrote:
>>>>>> Currently, Arm64 and x86 use the common code wehn parsing numa node
>>>>>> in a acpi way. The arm64 will set the parsed node in numa_add_memblk,
>>>>>> but the x86 is not set in that , then it will result in the repeatly
>>>>>> setting. And the parsed node maybe is unreasonable to the system.
>>>>>>
>>>>>> we would better not set it although it also still works. because the
>>>>>> parsed node is unresonable. so we should skip related operate in this
>>>>>> node. This patch just set node in various architecture individually.
>>>>>> it is no functional change.
>>>>> I really have hard time to understand what you try to say above. Could
>>>>> you start by the problem description and then how you are addressing it?
>>>> I am so sorry for that. I will make the issue clear.
>>>>
>>>> Arm64 get numa information through acpi. The code flow is as follows.
>>>>
>>>> arm64_acpi_numa_init
>>>> acpi_parse_memory_affinity
>>>> acpi_numa_memory_affinity_init
>>>> numa_add_memblk(nid, start, end); //it will set node to numa_nodes_parsed successfully.
>>>> node_set(node, numa_nodes_parsed); // numa_add_memblk had set that. it will repeat.
>>>>
>>>> the root cause is that X86 parse numa also go through above code. and arch-related
>>>> numa_add_memblk is not set the parsed node to numa_nodes_parsed. it need
>>>> additional node_set(node, numa_parsed) to handle. therefore, the issue will be introduced.
>>>>
>>> No it is not much more clear. I would have to go and re-study the whole
>>> code flow to see what you mean here. So you could simply state what _the
>>> issue_ is? How can user observe it and what are the consequences?
>> The patch do not fix a real issue. it is a cleanup.
>> because the acpi code is public, I find they are messy between
>> Arch64 and X86 when parsing numa message . therefore, I try to
>> make the code more clear between them.
> So make this explicit in the changelog. Your previous wording sounded
> like there is a _problem_ in the code.
>
:-[ please take some time to check. if it works. I will resend v2 with detailed changelog.

Thanks
zhongjiang