linux.git/tools/testing/selftests/damon, branch master

selftests/damon: check correct path in ensure_file() not_exist case

2026-08-05T02:18:29+00:00

In the ensure_file() function, the "not_exist" code path checks whether
$dir exists as a regular file.  However, the intent is to verify that the
target file ($file) does not exist, not the $dir.  Testing $dir makes the
existence check effectively useless -- it tests the wrong path and thus
never catches the case where the file is unexpectedly present.

Replace $dir with $file so the not_exist verification targets the correct
path.

Link: https://lore.kernel.org/20260706134305.5224-1-a929244872@163.com
Signed-off-by: wang wei 
Reviewed-by: SJ Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon/drgn_dump_damon_status: do not dump nr_accesses_bp

2026-07-31T02:40:35+00:00

drgn_dump_damon_status is dumping nr_accesses_bp field for future use
case.  nr_accesses_bp is not being used for a real purpose, though.  Hence
there will be no future test for it.  Do not dump it.

Link: https://lore.kernel.org/20260630040812.149729-13-sj@kernel.org
Signed-off-by: SJ Park 
Cc: Brendan Higgins 
Cc: "Masami Hiramatsu (Google)" 
Cc: Mathieu Desnoyers 
Cc: Shuah Khan 
Cc: Steven Rostedt 
Signed-off-by: Andrew Morton

selftests/damon/sysfs.sh: test all files in quota goal dir

2026-07-31T02:40:26+00:00

DAMON sysfs interface for DAMOS quota has quite extended since its initial
introduction.  The test case for that in DAMON sysfs interface essential
file operations test (sysfs.sh) has not accordingly extended, though. 
Extend the test case to test all existing files.

Link: https://lore.kernel.org/20260630141726.92246-8-sj@kernel.org
Signed-off-by: SJ Park 
Cc: Brendan Higgins 
Cc: David Hildenbrand 
Cc: Jonathan Corbet 
Cc: Liam R. Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/damon/sysfs.sh: test dests dir

2026-07-31T02:40:26+00:00

DAMON selftest interface essential file operations test (sysfs.sh) is not
testing DAMOS dests/ directory.  Add the test.

Link: https://lore.kernel.org/20260630141726.92246-7-sj@kernel.org
Signed-off-by: SJ Park 
Cc: Brendan Higgins 
Cc: David Hildenbrand 
Cc: Jonathan Corbet 
Cc: Liam R. Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/damon/sysfs.sh: test {core,ops}_filters/ directories

2026-07-31T02:40:26+00:00

DAMON sysfs interface essential file operations test (sysf.sh) is not
testing DAMOS {core,ops}_filters directories.  Add the tests.

Link: https://lore.kernel.org/20260630141726.92246-6-sj@kernel.org
Signed-off-by: SJ Park 
Cc: Brendan Higgins 
Cc: David Hildenbrand 
Cc: Jonathan Corbet 
Cc: Liam R. Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/damon/sysfs.sh: test multiple probe dirs creation

2026-07-31T02:40:26+00:00

DAMON sysfs essential file operations test (sysfs.sh) was extended to test
DAMON probes sysfs directory, by commit 14885da09b0f
("selftests/damon/sysfs.sh: test probes dir").  Unlike other DAMON sysfs
files, it is testing only a single directory case.  Extend it for multiple
directories.

Link: https://lore.kernel.org/20260630141726.92246-5-sj@kernel.org
Signed-off-by: SJ Park 
Cc: Brendan Higgins 
Cc: David Hildenbrand 
Cc: Jonathan Corbet 
Cc: Liam R. Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton

selftests/damon/sysfs_refresh: test kdamond refresh_ms

2026-07-29T04:12:11+00:00

Writing a non-zero value to a kdamond's 'refresh_ms' sysfs file should
make DAMON periodically update the read-only sysfs files on its own,
without the user writing update keywords such as 'update_schemes_stats' to
the 'state' file.  This behavior has no test coverage.

Add a test that starts a kdamond with refresh_ms set and a 'stat' scheme
whose default access pattern matches every monitored region, then polls
the scheme's 'nr_tried' stats file directly, without requesting an update.
The value can become non-zero only via the periodic refresh, so the test
confirms refresh_ms works; with refresh_ms disabled the stat stays zero
and the test fails.

Link: https://lore.kernel.org/20260602131217.2210912-3-linuxoid@gmail.com
Link: https://lore.kernel.org/20260629144927.134237-3-sj@kernel.org
Signed-off-by: Ruslan Valiyev 
Reviewed-by: SJ Park 
Signed-off-by: SJ Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon/_damon_sysfs: support kdamond refresh_ms

2026-07-29T04:12:11+00:00

Patch series "selftests/damon: test kdamond refresh_ms", v2.

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.


This patch (of 2):

The Kdamond class has no way to set the kdamond-level 'refresh_ms' sysfs
file, which makes DAMON periodically update the read-only sysfs files
(DAMOS stats, tuned monitoring intervals and the kdamond pid) on its own.

Add a 'refresh_ms' parameter to Kdamond.  When it is set (including to
zero, to disable the periodic update), write it before turning the kdamond
on, so tests can exercise the auto-update behavior.  Leaving it unset
keeps the previous behavior of not touching the file, so callers running
against kernels without the feature are unaffected.

Link: https://lore.kernel.org/20260602131217.2210912-2-linuxoid@gmail.com
Link: https://lore.kernel.org/20260629144927.134237-2-sj@kernel.org
Signed-off-by: Ruslan Valiyev 
Reviewed-by: SJ Park 
Signed-off-by: SJ Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon/sysfs.py: validate memcg_path staging readback

2026-07-29T04:12:11+00:00

Add a dedicated test at the end of main() that stages memcg_path via sysfs
and verifies its readback.  Configure the memcg filter before start(), do
not call commit(), and ignore start() failures so the test does not depend
on CONFIG_MEMCG or cgroup layout.  Call stop() for cleanup without
checking its return value.

Link: https://lore.kernel.org/D2B37130D38E09AC+20260601090634.241864-1-niecheng1@uniontech.com
Link: https://lore.kernel.org/20260629144812.134159-3-sj@kernel.org
Signed-off-by: Cheng Nie 
Signed-off-by: SJ Park 
Reviewed-by: SJ Park 
Signed-off-by: Andrew Morton

selftests/damon/_damon_sysfs.py: fix memcg_path assignment

2026-07-29T04:12:11+00:00

Patch series "selftests/damon: fix memcg_path staging handling", v5.

Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and add
a test case of it in sysfs.py.


This patch (of 2):

DamosFilter stores memcg_path for sysfs staging, but the constructor
assigns it with a trailing comma and therefore turns it into a tuple.

Fix the assignment so memcg_path is stored as the intended string.  This
makes memcg filter staging and follow-up validation use the written path
correctly.

Link: https://lore.kernel.org/20260629144812.134159-1-sj@kernel.org
Link: https://lore.kernel.org/464AE12D4BC6B6F4+20260601090519.240482-1-niecheng1@uniontech.com
Link: https://lore.kernel.org/20260629144812.134159-2-sj@kernel.org
Signed-off-by: Cheng Nie 
Signed-off-by: SJ Park 
Reviewed-by: SJ Park 
Signed-off-by: Andrew Morton