[PATCH v2 00/13] mm/sparse: remove SECTION_MARKED_PRESENT and further cleanups

[David Hildenbrand (Arm)]

SECTION_MARKED_PRESENT is really only needed during boot, where we
can instead just rely on SECTION_IS_EARLY_BIT by setting that flag
earlier.

Some preparations for doing that conversion and some cleanups in the same
(sparse) area.

Tested on x86 with and without memory hotplug through virtio-mem.

---
Changes in v2:
- Rebased to mm-unstable
- Add "scripts/gdb: mm.py: remove fallbacks for SECTION_HAS_MEM_MAP and
  SECTION_IS_EARLY"
- Improve comment in mmzone.h for __highest_used_section_nr
- Improve comment in fs/proc/page.c for get_max_dump_pfn()
- Move __highest_used_section_nr handling directly into
  __section_mark_present() callers and use max()
- Make pfn const in sparse_metadata_init_nid()
- Take care of .clang_format
- Smaller patch description fixes
- Link to v1: https://patch.msgid.link/20260909-b4-sparsemem_cleanups-v1-0-008fc8d579fe@xxxxxxxxxx

To: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
To: David Hildenbrand <david@xxxxxxxxxx>
To: Lorenzo Stoakes <ljs@xxxxxxxxxx>
To: "Liam R. Howlett" <liam@xxxxxxxxxxxxx>
To: Vlastimil Babka <vbabka@xxxxxxxxxx>
To: Mike Rapoport <rppt@xxxxxxxxxx>
To: Suren Baghdasaryan <surenb@xxxxxxxxxx>
To: Michal Hocko <mhocko@xxxxxxxx>
To: Kairui Song <kasong@xxxxxxxxxxx>
To: Qi Zheng <qi.zheng@xxxxxxxxx>
To: Shakeel Butt <shakeel.butt@xxxxxxxxx>
To: Barry Song <baohua@xxxxxxxxxx>
To: Axel Rasmussen <axelrasmussen@xxxxxxxxxx>
To: Yuanchu Xie <yuanchu@xxxxxxxxxx>
To: Wei Xu <weixugc@xxxxxxxxxx>
To: Baoquan He <baoquan.he@xxxxxxxxx>
To: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
To: Brendan Jackman <brendan.jackman@xxxxxxxxx>
To: Johannes Weiner <hannes@xxxxxxxxxxx>
To: Zi Yan <ziy@xxxxxxxxxx>
To: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
To: Kieran Bingham <kbingham@xxxxxxxxxx>
To: Oscar Salvador <osalvador@xxxxxxx>
To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
To: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
To: Danilo Krummrich <dakr@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: linux-cxl@xxxxxxxxxxxxxxx
Cc: driver-core@xxxxxxxxxxxxxxx
Cc: linux-fsdevel@xxxxxxxxxxxxxxx

---

David Hildenbrand (Arm) (13):
      mm/sparse: move mem_section init to sparse_extreme_init()
      mm/sparse: refactor sparse_sections_init()
      mm/sparse: move initialization of section metadata to sparse_metadata_init()
      mm/sparse: rename and cleanup sparse_init_nid()
      mm/sparse: cleanup sparse_init_one_section()
      mm/sparse: rename __highest_present_section_nr to __highest_used_section_nr
      mm/sparse: remove pfn_in_present_section()
      mm/sparse: move __highest_used_section_nr handling
      scripts/gdb: mm.py: remove fallbacks for SECTION_HAS_MEM_MAP and SECTION_IS_EARLY
      mm/sparse: remove SECTION_MARKED_PRESENT
      mm/sparse: remove flags parameter from sparse_init_one_section()
      fs/proc/page: clarify comment in get_max_dump_pfn()
      mm/memory_hotplug: drop CONFIG_HAVE_ARCH_PFN_VALID handling from pfn_to_online_page()

 .clang-format           |   2 +-
 drivers/base/memory.c   |   2 +-
 fs/proc/page.c          |   7 +--
 include/linux/cache.h   |   1 +
 include/linux/mmzone.h  |  43 ++++---------
 mm/compaction.c         |   2 +-
 mm/memory_hotplug.c     |   9 +--
 mm/sparse-vmemmap.c     |   4 +-
 mm/sparse.c             | 160 +++++++++++++++++++++++-------------------------
 mm/sparse.h             |  19 ++----
 scripts/gdb/linux/mm.py |   8 +--
 11 files changed, 108 insertions(+), 149 deletions(-)

---

base-commit: 8d61431ed2607386b427752505379536eb634ce8

change-id: 20260814-b4-sparsemem_cleanups-8bc4b47014c3

--

Cheers,

David