The kdamond 'refresh_ms' sysfs file makes DAMON periodically update its
read-only sysfs files (DAMOS stats, tuned monitoring intervals and the
kdamond pid) on its own, so users don't have to write update keywords
such as 'update_schemes_stats' to the 'state' file.  It has no selftest
coverage.

The first patch adds refresh_ms support to the _damon_sysfs.py test
control module.  The second adds a test that sets refresh_ms and confirms
a scheme's stats are updated under sysfs without an explicit update
request; the test skips on kernels that predate the refresh_ms file.

Tested on current mainline under a DAMON-enabled kernel: the new test
passes and the existing DAMON selftests show no new failures.

Ruslan Valiyev (2):
  selftests/damon/_damon_sysfs: support kdamond refresh_ms
  selftests/damon/sysfs_refresh: test kdamond refresh_ms

 tools/testing/selftests/damon/Makefile        |  1 +
 tools/testing/selftests/damon/_damon_sysfs.py |  9 ++-
 .../testing/selftests/damon/sysfs_refresh.py  | 75 +++++++++++++++++++
 3 files changed, 84 insertions(+), 1 deletion(-)
 create mode 100755 tools/testing/selftests/damon/sysfs_refresh.py


base-commit: 174914ea551314c52a61713b9c4bde9e42d48073
-- 
2.43.0

On Tue,  2 Jun 2026 15:12:15 +0200 Ruslan Valiyev <linuxoid@gmail.com> wrote:

> The kdamond 'refresh_ms' sysfs file makes DAMON periodically update its
> read-only sysfs files (DAMOS stats, tuned monitoring intervals and the
> kdamond pid) on its own, so users don't have to write update keywords
> such as 'update_schemes_stats' to the 'state' file.  It has no selftest
> coverage.
> 
> The first patch adds refresh_ms support to the _damon_sysfs.py test
> control module.  The second adds a test that sets refresh_ms and confirms
> a scheme's stats are updated under sysfs without an explicit update
> request; the test skips on kernels that predate the refresh_ms file.
> 
> Tested on current mainline under a DAMON-enabled kernel: the new test
> passes and the existing DAMON selftests show no new failures.

Thank you for this great contribution, Ruslan! :)

All patches look good.  I therefore added this sereis to damon/next [1] tree.
If this series is not added to mm.git in short term (~1 week?), I will ask
mm.git maintainer (Andrew Morton) to pick this.

Andrew might want us to wait until next rc1 release, though, as
apparently now we want to keep more time on stabilizing mm.git for the next
merge window.  Andrew, please let me know if so.

So, no action from your side is needed for now.  If it seems I
also forgot doing that or you cannot wait for my action, please feel free to
directly ask that to Andrew.

[1] https://origin.kernel.org/doc/html/latest/mm/damon/maintainer-profile.html#scm-trees


Thanks,
SJ

[...]

On Tue,  2 Jun 2026 07:28:03 -0700 SeongJae Park <sj@kernel.org> wrote:

> Andrew might want us to wait until next rc1 release, though, as
> apparently now we want to keep more time on stabilizing mm.git for the next
> merge window.  Andrew, please let me know if so.

Yes, awaiting -rc1 would be preferred please.

On Tue, 2 Jun 2026 10:03:08 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:

> On Tue,  2 Jun 2026 07:28:03 -0700 SeongJae Park <sj@kernel.org> wrote:
> 
> > Andrew might want us to wait until next rc1 release, though, as
> > apparently now we want to keep more time on stabilizing mm.git for the next
> > merge window.  Andrew, please let me know if so.
> 
> Yes, awaiting -rc1 would be preferred please.

Thank you for letting me know.  I will hold reposting of this until the -rc1.

Ruslan, please let us know if you think this series cannot wait.


Thanks,
SJ