RFC mm/damon: improve readability, clarity and test coverage

Yet another batch of miscellaneous DAMON minor improvements. Mostly focused on readability and clarity of code and document, and unit/self test coverage. No user-visible behavioral change is intended.

Changes from RFC
- RFC: https://lore.kernel.org/[email protected]
- Fix a typo in the selftest warning message.
- Collect A-b: from Randy.
- Split out damos_adjust_quota() fix to an individual hotfix patch.
- Add a patch for initializing walk_control_obsolete in damon_new_ctx().
- Add a patch for probe_hits_wsum damos filter commit kunit test.
- Trivial patch sequence update.
- Rebase to the latest mm-new.

SJ Park (10):
mm/damon/api: remove NR_DAMOS_FILTER_TYPES
mm/damon/core: use abs_diff() in damon_feed_loop_next_input() mm/damon/core: use mult_frac() in damon_feed_loop_next_input() mm/damon/core: set damon_ctx->walk_control_obsolete in damon_new_ctx() mm/damon/core: document damon_call()/damon_start() race hang issue mm/damon/paddr: remove pa parameter from damon_pa_filter_pass() mm/damon/tests/core-kunit: test eligible_mem_bp commitment mm/damon/tests/core-kunit: add probe_hits_wsum damos filter commit
test
selftests/damon/sysfs_memcg_path_leak: fail only for real DAMON leak Docs/mm/damon/design: clarify bp is basis point

 Documentation/mm/damon/design.rst             |  5 ++--
 include/linux/damon.h                         |  2 --
 mm/damon/core.c                               | 19 ++++--------
 mm/damon/paddr.c                              |  5 ++--
 mm/damon/tests/core-kunit.h                   | 30 +++++++++++++++++++
 .../selftests/damon/sysfs_memcg_path_leak.sh  |  7 +++++
 6 files changed, 48 insertions(+), 20 deletions(-)

base-commit: b7c76a308c2afda7cfc2ce98be3eed466be71337

2.47.3