+ selftests-damon-add-a-test-for-damos-quota.patch added to mm-unstable branch

+ selftests-damon-add-a-test-for-damos-quota.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: selftests/damon: add a test for DAMOS quota
has been added to the -mm mm-unstable branch.  Its filename is
     selftests-damon-add-a-test-for-damos-quota.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-damon-add-a-test-for-damos-quota.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: SeongJae Park <sj@kernel.org>
Subject: selftests/damon: add a test for DAMOS quota
Date: Wed, 7 Feb 2024 12:31:30 -0800

Add a selftest for verifying the DAMOS quota feature.  The test is very
similar to sysfs_update_schemes_tried_regions_wss_estimation.py.  It
starts an artificial workload of 20 MiB working set, run DAMON to find the
working set size, but with 1 MiB/100 ms size quota.  Then, it collect the
DAMON-found working set size every 100 ms and check if the quota was
always applied as expected.  For the confirmation, the tests shows the
stat-applied region size and the qt_exceeds stat.

Link: https://lkml.kernel.org/r/20240207203134.69976-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/damon/Makefile       |    1 
 tools/testing/selftests/damon/damos_quota.py |   67 +++++++++++++++++
 2 files changed, 68 insertions(+)

--- /dev/null
+++ a/tools/testing/selftests/damon/damos_quota.py
@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+import subprocess
+import time
+
+import _damon_sysfs
+
+def main():
+    # access two 10 MiB memory regions, 2 second per each
+    sz_region = 10 * 1024 * 1024
+    proc = subprocess.Popen(['./access_memory', '2', '%d' % sz_region, '2000'])
+
+    # Set quota up to 1 MiB per 100 ms
+    sz_quota = 1024 * 1024 # 1 MiB
+    quota_reset_interval = 100 # 100 ms
+    kdamonds = _damon_sysfs.Kdamonds([_damon_sysfs.Kdamond(
+            contexts=[_damon_sysfs.DamonCtx(
+                ops='vaddr',
+                targets=[_damon_sysfs.DamonTarget(pid=proc.pid)],
+                schemes=[_damon_sysfs.Damos(
+                    access_pattern=_damon_sysfs.DamosAccessPattern(
+                        # >= 25% access rate, >= 200ms age
+                        nr_accesses=[5, 20], age=[2, 2**64 - 1]),
+                    quota=_damon_sysfs.DamosQuota(
+                        sz=sz_quota, reset_interval_ms=quota_reset_interval)
+                    )] # schemes
+                )] # contexts
+            )]) # kdamonds
+
+    err = kdamonds.start()
+    if err != None:
+        print('kdamond start failed: %s' % err)
+        exit(1)
+
+    wss_collected = []
+    nr_quota_exceeds = 0
+    while proc.poll() == None:
+        time.sleep(0.1)
+        err = kdamonds.kdamonds[0].update_schemes_tried_bytes()
+        if err != None:
+            print('tried bytes update failed: %s' % err)
+            exit(1)
+        err = kdamonds.kdamonds[0].update_schemes_stats()
+        if err != None:
+            print('stats update failed: %s' % err)
+            exit(1)
+
+        scheme = kdamonds.kdamonds[0].contexts[0].schemes[0]
+        wss_collected.append(scheme.tried_bytes)
+        nr_quota_exceeds = scheme.stats.qt_exceeds
+
+    wss_collected.sort()
+    for wss in wss_collected:
+        if wss > sz_quota:
+            print('quota is not kept: %s > %s' % (wss, sz_quota))
+            print('collected samples are as below')
+            print('\n'.join(['%d' % wss for wss in wss_collected]))
+            exit(1)
+
+    if nr_quota_exceeds < len(wss_collected):
+        print('quota is not always exceeded: %d > %d' %
+              (len(wss_collected), nr_quota_exceeds))
+        exit(1)
+
+if __name__ == '__main__':
+    main()
--- a/tools/testing/selftests/damon/Makefile~selftests-damon-add-a-test-for-damos-quota
+++ a/tools/testing/selftests/damon/Makefile
@@ -12,6 +12,7 @@ TEST_PROGS += debugfs_rm_non_contexts.sh
 TEST_PROGS += sysfs.sh sysfs_update_removed_scheme_dir.sh
 TEST_PROGS += sysfs_update_schemes_tried_regions_hang.py
 TEST_PROGS += sysfs_update_schemes_tried_regions_wss_estimation.py
+TEST_PROGS += damos_quota.py
 TEST_PROGS += reclaim.sh lru_sort.sh
 
 include ../lib.mk
_

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-sysfs-schemes-fix-wrong-damos-tried-regions-update-timeout-setup.patch
mm-damon-core-check-apply-interval-in-damon_do_apply_schemes.patch
docs-admin-guide-mm-damon-usage-use-sysfs-interface-for-tracepoints-example.patch
mm-damon-rename-config_damon_dbgfs-to-damon_dbgfs_deprecated.patch
mm-damon-dbgfs-implement-deprecation-notice-file.patch
mm-damon-dbgfs-make-debugfs-interface-deprecation-message-a-macro.patch
docs-admin-guide-mm-damon-usage-document-deprecated-file-of-damon-debugfs-interface.patch
selftets-damon-prepare-for-monitor_on-file-renaming.patch
mm-damon-dbgfs-rename-monitor_on-file-to-monitor_on_deprecated.patch
docs-admin-guide-mm-damon-usage-update-for-monitor_on-renaming.patch
docs-translations-damon-usage-update-for-monitor_on-renaming.patch
mm-damon-sysfs-handle-state-file-inputs-for-every-sampling-interval-if-possible.patch
selftests-damon-_damon_sysfs-support-damos-quota.patch
selftests-damon-_damon_sysfs-support-damos-stats.patch
selftests-damon-_damon_sysfs-support-damos-apply-interval.patch
selftests-damon-add-a-test-for-damos-quota.patch
selftests-damon-add-a-test-for-damos-apply-intervals.patch
selftests-damon-add-a-test-for-a-race-between-target_ids_read-and-dbgfs_before_terminate.patch
selftests-damon-add-a-test-for-the-pid-leak-of-dbgfs_target_ids_write.patch
selftests-damon-_chk_dependency-get-debugfs-mount-point-from-proc-mounts.patch