RE: [PATCH v5 0/5] mm/memory_hotplug: optimize zone contiguous check when changing pfn range

[Liu, Yuan1]

> -----Original Message-----
> From: Mike Rapoport <rppt@xxxxxxxxxx>
> Sent: Monday, June 1, 2026 3:18 PM
> To: Liu, Yuan1 <yuan1.liu@xxxxxxxxx>
> Cc: David Hildenbrand <david@xxxxxxxxxx>; Oscar Salvador
> <osalvador@xxxxxxx>; Wei Yang <richard.weiyang@xxxxxxxxx>; 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>; Zeng, Jason <jason.zeng@xxxxxxxxx>; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v5 0/5] mm/memory_hotplug: optimize zone contiguous
> check when changing pfn range
> 
> Hi,
> 
> On Wed, May 20, 2026 at 05:34:52AM -0400, Yuan Liu wrote:
> > This series introduces a pages_with_online_memmap member into struct
> zone
> > to avoid pageblock-by-pageblock scans across the entire zone and improve
> > memory hotplug performance.
> >
> > For VM hotplug performance data, please refer to Patch 4.
> > This series also benefits CXL hotplug. Performance results are as
> follows
> > https://lore.kernel.org/all/20260409023552.GA2807@AE/
> >
> > Yuan Liu (5):
> >   mm: move mirrored memory overlap checking to the outer loop
> >   mm: skip non-mirrored ZONE_NORMAL memory map init when
> >     kernelcore=mirror
> >   mm: remove the special early-section handling from pfn_valid() and
> >     for_each_valid_pfn()
> >   mm/memory_hotplug: optimize zone contiguous check when changing pfn
> >     range
> >   mm/memory_hotplug: improve shrink_zone_span() subsection boundary
> >     checks
> >
> >  Documentation/mm/physical_memory.rst | 13 +++++
> >  drivers/base/memory.c                |  6 ++
> >  include/linux/mmzone.h               | 60 +++++++++++++++++---
> >  mm/internal.h                        |  8 +--
> >  mm/memory_hotplug.c                  | 54 +++++++++---------
> >  mm/mm_init.c                         | 83 +++++++++++-----------------
> >  mm/sparse-vmemmap.c                  |  4 +-
> >  7 files changed, 136 insertions(+), 92 deletions(-)
> 
> Sashiko has a few comments:
> https://sashiko.dev/#/patchset/20260520093457.3719960-3-
> yuan1.liu@xxxxxxxxx
> 
> Can you please check them?

Hi Mike

Thanks for the reminder. I will take a closer look at Sashiko's comments.

> --
> Sincerely yours,
> Mike.