linux.git/tools/testing/selftests/damon, branch v6.11

selftests/damon/damon_nr_regions: test online-tuned max_nr_regions

2024-07-04T02:30:29+00:00

User could update max_nr_regions parameter while DAMON is running to a
value that smaller than the current number of regions that DAMON is
seeing.  Such update could be done for reducing the monitoring overhead. 
In the case, DAMON should merge regions aggressively more than normal
situation to ensure the new limit is successfully applied.  Implement a
kselftest to ensure that.

Link: https://lkml.kernel.org/r/20240625180538.73134-9-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

_damon_sysfs: implement commit() for online parameters update

2024-07-04T02:30:29+00:00

Users can update DAMON parameters while it is running, using 'commit'
DAMON sysfs interface command.  For testing the feature in future tests,
implement a function for doing that on the test-purpose DAMON sysfs
interface wrapper Python module.

Link: https://lkml.kernel.org/r/20240625180538.73134-8-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon: implement test for min/max_nr_regions

2024-07-04T02:30:29+00:00

Implement a kselftest for DAMON's {min,max}_nr_regions' parameters.  The
test ensures both the minimum and the maximum number of regions limit is
respected even if the workload's real number of regions is less than the
minimum or larger than the maximum limits.

Link: https://lkml.kernel.org/r/20240625180538.73134-7-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon/_damon_sysfs: implement kdamonds stop function

2024-07-04T02:30:28+00:00

Implement DAMON stop function on the test-purpose DAMON sysfs interface
wrapper Python module, _damon_sysfs.py.  This feature will be used by
future DAMON tests that need to start/stop DAMON multiple times.

Link: https://lkml.kernel.org/r/20240625180538.73134-6-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon: implement DAMOS tried regions test

2024-07-04T02:30:28+00:00

Implement a test for DAMOS tried regions command of DAMON sysfs interface.
It ensures the expected number of monitoring regions are created using an
artificial memory access pattern generator program.

Link: https://lkml.kernel.org/r/20240625180538.73134-5-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon: implement a program for even-numbered memory regions access

2024-07-04T02:30:28+00:00

To test schemes_tried_regions feature, we need to have a program having
specific number of regions that having different access pattern.  Existing
artificial access pattern generator, 'access_memory', cannot be used for
the purpose, since it accesses only one region at a given time.  Extending
it could be an option, but since the purpose and the implementation are
pretty simple, implementing another one from the scratch is better.

Implement such another artificial memory access program that allocates
user-defined number/size regions and accesses even-numbered regions.

Link: https://lkml.kernel.org/r/20240625180538.73134-4-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon/_damon_sysfs: support schemes_update_tried_regions

2024-07-04T02:30:28+00:00

Implement schemes_update_tried_regions DAMON sysfs command on
_damon_sysfs.py, to use on implementations of future tests for the
feature.

Link: https://lkml.kernel.org/r/20240625180538.73134-3-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon/access_memory: use user-defined region size

2024-07-04T02:30:28+00:00

Patch series "selftests/damon: test DAMOS tried regions and
{min,max}_nr_regions".

This patch series fix a minor issue in a program for DAMON selftest, and
implement new functionality selftests for DAMOS tried regions and
{min,max}_nr_regions.  The test for max_nr_regions also test the recovery
from online tuning-caused limit violation, which was fixed by a previous
patch [1] titled "mm/damon/core: merge regions aggressively when
max_nr_regions is unmet".

The first patch fixes a minor problem in the articial memory access
pattern generator for tests.  Following 3 patches (2-4) implement schemes
tried regions test.  Then a couple of patches (5-6) implementing static
setup based {min,max}_nr_regions functionality test follows.  Final two
patches (7-8) implement dynamic max_nr_regions update test.

[1] https://lore.kernel.org/20240624210650.53960C2BBFC@smtp.kernel.org


This patch (of 8):

'access_memory' is an artificial memory access pattern generator for DAMON
tests.  It creates and accesses memory regions that the user specified the
number and size via the command line.  However, real access part of the
program ignores the user-specified size of each region.  Instead, it uses
a hard-coded value, 10 MiB.  Fix it to use user-defined size.

Note that all existing 'access_memory' users are setting the region size
as 10 MiB.  Hence no real problem has happened so far.

Link: https://lkml.kernel.org/r/20240625180538.73134-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20240625180538.73134-2-sj@kernel.org
Fixes: b5906f5f7359 ("selftests/damon: add a test for update_schemes_tried_regions sysfs command")
Signed-off-by: SeongJae Park 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon: classify tests for functionalities and regressions

2024-05-11T22:41:34+00:00

DAMON selftests can be classified into two categories: functionalities and
regressions.  Functionality tests are for checking if the function is
working as specified, while the regression tests are basically reproducers
of previously reported and fixed bugs.  The tests of the categories are
mixed in the selftests Makefile.  Separate those for easier understanding
of the types of tests.

Link: https://lkml.kernel.org/r/20240503180318.72798-6-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Jonathan Corbet 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'

2024-05-11T22:41:34+00:00

_damon_sysfs.py is using '==' or '!=' for 'None'.  Since 'None' is a
singleton, using 'is' or 'is not' is more efficient.  Use the more
efficient one.

Link: https://lkml.kernel.org/r/20240503180318.72798-5-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Jonathan Corbet 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton