[PATCH v3 0/4] Optimize folio split in memory failure

[Zi Yan <ziy@nvidia.com>]

Hi all,

This patchset is a follow-up of "[PATCH v3] mm/huge_memory: do not change
split_huge_page*() target order silently."[1]. It improves how memory
failure code handles large block size(LBS) folios with
min_order_for_split() > 0. By splitting a large folio containing HW
poisoned pages to min_order_for_split(), the after-split folios without
HW poisoned pages could be freed for reuse. To achieve this, folio split
code needs to set has_hwpoisoned on after-split folios containing HW
poisoned pages.

This patchset includes:
1. A patch sets has_hwpoisoned on the right after-split folios after
   scanning all pages in the folios,
2. A patch adds split_huge_page_to_order(),
3. Patch 2 and Patch 3 of "[PATCH v2 0/3] Do not change split folio target
   order"[2],

This patchset is based on mm-new.

Changelog
===
From V2[2]:
1. Patch 1 is sent separately as a hotfix[1].
2. set has_hwpoisoned on after-split folios if any contains HW poisoned
   pages.
3. added split_huge_page_to_order().
4. added a missing newline after variable decalaration.
5. added /* release= */ to try_to_split_thp_page().
6. restructured try_to_split_thp_page() in memory_failure().
7. fixed a typo.
8. clarified the comment in soft_offline_in_use_page().


Link: https://lore.kernel.org/all/20251017013630.139907-1-ziy@nvidia.com/ [1]
Link: https://lore.kernel.org/all/20251016033452.125479-1-ziy@nvidia.com/ [2]

Zi Yan (4):
  mm/huge_memory: preserve PG_has_hwpoisoned if a folio is split to >0
    order
  mm/huge_memory: add split_huge_page_to_order()
  mm/memory-failure: improve large block size folio handling.
  mm/huge_memory: fix kernel-doc comments for folio_split() and related.

 include/linux/huge_mm.h | 22 ++++++++++++-----
 mm/huge_memory.c        | 55 ++++++++++++++++++++++++++++++-----------
 mm/memory-failure.c     | 30 +++++++++++++++++++---
 3 files changed, 82 insertions(+), 25 deletions(-)

-- 
2.51.0