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

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

[Andrew Morton]

The patch titled
     Subject: selftests/damon: add a test for DAMOS apply intervals
has been added to the -mm mm-unstable branch.  Its filename is
     selftests-damon-add-a-test-for-damos-apply-intervals.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-apply-intervals.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 apply intervals
Date: Wed, 7 Feb 2024 12:31:31 -0800

Add a selftest for DAMOS apply intervals.  It runs two schemes having
different apply interval agains an artificial memory access workload, and
check if the scheme with smaller apply interval was applied more
frequently.

Link: https://lkml.kernel.org/r/20240207203134.69976-6-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                |    2 
 tools/testing/selftests/damon/damos_apply_interval.py |   67 ++++++++++
 2 files changed, 68 insertions(+), 1 deletion(-)

--- /dev/null
+++ a/tools/testing/selftests/damon/damos_apply_interval.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
+    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]),
+                        # aggregation interval (100 ms) is used
+                        apply_interval_us=0),
+                    # use 10ms apply interval
+                    _damon_sysfs.Damos(
+                        access_pattern=_damon_sysfs.DamosAccessPattern(
+                            # >= 25% access rate, >= 200ms age
+                            nr_accesses=[5, 20], age=[2, 2**64 - 1]),
+                        # explicitly set 10 ms apply interval
+                        apply_interval_us=10 * 1000)
+                    ] # 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_stats()
+        if err != None:
+            print('stats update failed: %s' % err)
+            exit(1)
+    schemes = kdamonds.kdamonds[0].contexts[0].schemes
+    nr_tried_stats = [s.stats.nr_tried for s in schemes]
+    if nr_tried_stats[0] == 0 or nr_tried_stats[1] == 0:
+        print('scheme(s) are not tried')
+        exit(1)
+
+    # Because the second scheme was having the apply interval that is ten times
+    # lower than that of the first scheme, the second scheme should be tried
+    # about ten times more frequently than the first scheme.  For possible
+    # timing errors, check if it was at least nine times more freuqnetly tried.
+    ratio = nr_tried_stats[1] / nr_tried_stats[0]
+    if ratio < 9:
+        print('%d / %d = %f (< 9)' %
+              (nr_tried_stats[1], nr_tried_stats[0], ratio))
+        exit(1)
+
+if __name__ == '__main__':
+    main()
--- a/tools/testing/selftests/damon/Makefile~selftests-damon-add-a-test-for-damos-apply-intervals
+++ a/tools/testing/selftests/damon/Makefile
@@ -12,7 +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 += damos_quota.py damos_apply_interval.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