Re: [PATCH v4 0/2] mm/memory hotplug/unplug: Optimize zone contiguous check when changing pfn range

[David Hildenbrand (Arm)]

On 4/22/26 09:56, Liu, Yuan1 wrote:
>> -----Original Message-----
>> From: David Hildenbrand (Arm) <david@xxxxxxxxxx>
>> Sent: Wednesday, April 22, 2026 3:47 PM
>> To: Liu, Yuan1 <yuan1.liu@xxxxxxxxx>; Oscar Salvador <osalvador@xxxxxxx>;
>> Mike Rapoport <rppt@xxxxxxxxxx>; Wei Yang <richard.weiyang@xxxxxxxxx>
>> Cc: linux-mm@xxxxxxxxx; Hu, Yong <yong.hu@xxxxxxxxx>; Zou, Nanhai
>> <nanhai.zou@xxxxxxxxx>; Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>; Zhuo, Qiuxu
>> <qiuxu.zhuo@xxxxxxxxx>; Chen, Yu C <yu.c.chen@xxxxxxxxx>; Deng, Pan
>> <pan.deng@xxxxxxxxx>; Li, Tianyou <tianyou.li@xxxxxxxxx>; Chen Zhang
>> <zhangchen.kidd@xxxxxx>; linux-kernel@xxxxxxxxxxxxxxx
>> Subject: Re: [PATCH v4 0/2] mm/memory hotplug/unplug: Optimize zone
>> contiguous check when changing pfn range
>>
>> On 4/21/26 14:55, Yuan Liu wrote:
>>> This series cleans up the overlap memory map init check and
>>> optimizes zone contiguous check when changing pfn range.
>>>
>>> In addition to providing a significant improvement for VM hotplug
>>> (see the second patch for reference), it brings benefits for CXL
>>> hotplug as well. The link is as follows
>>> https://lore.kernel.org/all/20260409023552.GA2807@AE/
>>>
>>> v3 link:
>>>     https://lore.kernel.org/all/20260408031615.1831922-1-
>> yuan1.liu@xxxxxxxxx/
>>>
>>> v4 changes:
>>>     Add a new patch for clean up overlap memory map init check
>>
>> Didn't you also wanted to add a patch to improve shrink_zone_span to check
>> both
>> sides of the PAGES_PER_SUBSECTION block for fitting nid+zid?
> 
> Hi David
> 
> My apologies for missing this. I will include it in the next version.

And isn't there also the problem with the subsection pfn_valid() handling etc
where I proposed a change?

-- 
Cheers,

David