diff mbox series

[8/8] selftests/damon/damon_nr_regions: test online-tuned max_nr_regions

Message ID 20240625180538.73134-9-sj@kernel.org
State Accepted
Commit 8bf890c8161215bd1fbd1a6d9b61acbb8eac165b
Headers show
Series selftests/damon: test DAMOS tried regions and {min,max}_nr_regions | expand

Commit Message

SeongJae Park June 25, 2024, 6:05 p.m. UTC 
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.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 .../selftests/damon/damon_nr_regions.py       | 60 +++++++++++++++++++
 1 file changed, 60 insertions(+)
diff mbox series

Patch

diff --git a/tools/testing/selftests/damon/damon_nr_regions.py b/tools/testing/selftests/damon/damon_nr_regions.py
index dd2735923c59..2e8a74aff543 100644
--- a/tools/testing/selftests/damon/damon_nr_regions.py
+++ b/tools/testing/selftests/damon/damon_nr_regions.py
@@ -81,5 +81,65 @@  def main():
     # test max_nr_regions smaller than real nr regions
     test_nr_regions(15, 3, 10)
 
+    # test online-tuned max_nr_regions that smaller than real nr regions
+    sz_region = 10 * 1024 * 1024
+    proc = subprocess.Popen(['./access_memory_even', '14', '%d' % sz_region])
+
+    # stat every monitored regions
+    kdamonds = _damon_sysfs.Kdamonds([_damon_sysfs.Kdamond(
+            contexts=[_damon_sysfs.DamonCtx(
+                monitoring_attrs=_damon_sysfs.DamonAttrs(
+                    min_nr_regions=10, max_nr_regions=1000),
+                ops='vaddr',
+                targets=[_damon_sysfs.DamonTarget(pid=proc.pid)],
+                schemes=[_damon_sysfs.Damos(action='stat',
+                    )] # schemes
+                )] # contexts
+            )]) # kdamonds
+
+    err = kdamonds.start()
+    if err is not None:
+        proc.terminate()
+        print('kdamond start failed: %s' % err)
+        exit(1)
+
+    # wait until the real regions are found
+    time.sleep(3)
+
+    attrs = kdamonds.kdamonds[0].contexts[0].monitoring_attrs
+    attrs.min_nr_regions = 3
+    attrs.max_nr_regions = 7
+    err = kdamonds.kdamonds[0].commit()
+    if err is not None:
+        proc.terminate()
+        print('commit failed: %s' % err)
+        exit(1)
+    # wait for next merge operation is executed
+    time.sleep(0.3)
+
+    err = kdamonds.kdamonds[0].update_schemes_tried_regions()
+    if err is not None:
+        proc.terminate()
+        print('tried regions update failed: %s' % err)
+        exit(1)
+
+    scheme = kdamonds.kdamonds[0].contexts[0].schemes[0]
+    if scheme.tried_regions is None:
+        proc.terminate()
+        print('tried regions is not collected')
+        exit(1)
+
+    nr_tried_regions = len(scheme.tried_regions)
+    if nr_tried_regions <= 0:
+        proc.terminate()
+        print('tried regions is not created')
+        exit(1)
+    proc.terminate()
+
+    if nr_tried_regions > 7:
+        print('fail online-tuned max_nr_regions: %d > 7' % nr_tried_regions)
+        exit(1)
+    print('pass online-tuned max_nr_regions')
+
 if __name__ == '__main__':
     main()