selftests/damon: add script dir to sys.path for PYTHONSAFEPATH compatibility

Running these tests under Python's safe path mode, either with -P on the
interpreter command line or with PYTHONSAFEPATH set in the environment,
stops the script's own directory being prepended to sys.path.  Some
distributions (RHEL, for example) build the tests with -P in the shebang.

This breaks all 7 DAMON Python selftests that import the _damon_sysfs
helper module located in the same directory:

  ModuleNotFoundError: No module named '_damon_sysfs'

Fix this by explicitly adding the script's directory to sys.path before
importing _damon_sysfs, following the same pattern used in commit
c3b3eb565bd7 ("tools: ynl: add script dir to sys.path") which fixed the
identical issue for the YNL tools.

Link: https://lore.kernel.org/20260914141952.91465-4-sj@kernel.org
Signed-off-by: Eva Kurchatova <eva.kurchatova@virtuozzo.com>
Reviewed-by: SJ Park <sj@kernel.org>
Signed-off-by: SJ Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@davidgow.net>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kunwu Chan <kunwu.chan@gmail.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lian Wang <lianux.mm@gmail.com>
Cc: Liew Rui Yan <aethernet65535@gmail.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: "Zenghui Yu (Huawei)" <zenghui.yu@linux.dev>

7 files changed, 21 insertions, 0 deletions

diff --git a/tools/testing/selftests/damon/damon_nr_regions.py b/tools/testing/selftests/damon/damon_nr_regions.py
index 58f3291fed12..e55239813c65 100755
--- a/tools/testing/selftests/damon/damon_nr_regions.py
+++ b/tools/testing/selftests/damon/damon_nr_regions.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
+import os
 import subprocess
+import sys
 import time
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 import _damon_sysfs
 
 def test_nr_regions(real_nr_regions, min_nr_regions, max_nr_regions):
diff --git a/tools/testing/selftests/damon/damos_apply_interval.py b/tools/testing/selftests/damon/damos_apply_interval.py
index 0f2f36584e48..0bf7768b2006 100755
--- a/tools/testing/selftests/damon/damos_apply_interval.py
+++ b/tools/testing/selftests/damon/damos_apply_interval.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
+import os
 import subprocess
+import sys
 import time
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 import _damon_sysfs
 
 def main():
diff --git a/tools/testing/selftests/damon/damos_quota.py b/tools/testing/selftests/damon/damos_quota.py
index 57c4937aaed2..879115a499bf 100755
--- a/tools/testing/selftests/damon/damos_quota.py
+++ b/tools/testing/selftests/damon/damos_quota.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
+import os
 import subprocess
+import sys
 import time
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 import _damon_sysfs
 
 def main():
diff --git a/tools/testing/selftests/damon/damos_quota_goal.py b/tools/testing/selftests/damon/damos_quota_goal.py
index 661e4ba4765a..fed033a0afdf 100755
--- a/tools/testing/selftests/damon/damos_quota_goal.py
+++ b/tools/testing/selftests/damon/damos_quota_goal.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
+import os
 import subprocess
+import sys
 import time
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 import _damon_sysfs
 
 def main():
diff --git a/tools/testing/selftests/damon/damos_tried_regions.py b/tools/testing/selftests/damon/damos_tried_regions.py
index d6472e6a6e08..6941f87c10b1 100755
--- a/tools/testing/selftests/damon/damos_tried_regions.py
+++ b/tools/testing/selftests/damon/damos_tried_regions.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
+import os
 import subprocess
+import sys
 import time
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 import _damon_sysfs
 
 def main():
diff --git a/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_hang.py b/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_hang.py
index 28c887a0108f..625761c243b5 100755
--- a/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_hang.py
+++ b/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_hang.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
+import os
 import subprocess
+import sys
 import time
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 import _damon_sysfs
 
 def main():
diff --git a/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_wss_estimation.py b/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_wss_estimation.py
index 16fdc6e7fc56..36e7ae5f826d 100755
--- a/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_wss_estimation.py
+++ b/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_wss_estimation.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0
 
+import os
 import subprocess
+import sys
 import time
 
+sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 import _damon_sysfs
 
 def pass_wss_estimation(sz_region):