[PATCH v3 0/2] mm: collect the number of anon mTHP

[Barry Song <21cnbao@gmail.com>]

From: Barry Song <v-songbaohua@oppo.com>

Knowing the number of anon mTHPs in the system is crucial for performance
analysis. It helps in understanding the ratio and distribution of
mTHPs versus small folios throughout the system.

Additionally, partial unmapping by userspace can lead to significant waste
of mTHPs over time and increase memory reclamation pressure. We need this
information for comprehensive system tuning.

-v3:
 * collect David's acked-by, thanks!
 * rename nr_split_deferred to meaningful name - nr_anon_partially_mapped,
   per David. Ryan, I assume you will like it after you come back :-)

-v2:
 https://lore.kernel.org/linux-mm/20240811224940.39876-1-21cnbao@gmail.com/
 * don't rely on rmap to implement - 1, uses folio_free, split etc.
   Thanks for David's comment;
 * rename sys counters and refine doc. Thanks for Ryan's comment;

-v1:
 https://lore.kernel.org/all/20240808010457.228753-1-21cnbao@gmail.com/

Barry Song (2):
  mm: collect the number of anon large folios
  mm: collect the number of anon large folios partially mapped

 Documentation/admin-guide/mm/transhuge.rst | 10 ++++++++++
 include/linux/huge_mm.h                    | 16 ++++++++++++++--
 mm/huge_memory.c                           | 19 ++++++++++++++++---
 mm/migrate.c                               |  4 ++++
 mm/page_alloc.c                            |  5 ++++-
 mm/rmap.c                                  |  1 +
 6 files changed, 49 insertions(+), 6 deletions(-)

-- 
2.39.3 (Apple Git-146)