selftests/damon/_damon_sysfs: skip testcases if CONFIG_DAMON_SYSFS is disabled

When CONFIG_DAMON_SYSFS is disabled, the selftests fail with the following
outputs,

not ok 2 selftests: damon: sysfs_update_schemes_tried_regions_wss_estimation.py # exit=1
not ok 3 selftests: damon: damos_quota.py # exit=1
not ok 4 selftests: damon: damos_quota_goal.py # exit=1
not ok 5 selftests: damon: damos_apply_interval.py # exit=1
not ok 6 selftests: damon: damos_tried_regions.py # exit=1
not ok 7 selftests: damon: damon_nr_regions.py # exit=1
not ok 11 selftests: damon: sysfs_update_schemes_tried_regions_hang.py # exit=1

The root cause of this issue is that all the testcases above do not check
the sysfs interface of DAMON whether it exists or not.  With this patch
applied, all the testcases above now pass successfully.

Link: https://lkml.kernel.org/r/20250531093937.1555159-1-lienze@kylinos.cn
Signed-off-by: Enze Li <lienze@kylinos.cn>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/tools/testing/selftests/damon/_damon_sysfs.py b/tools/testing/selftests/damon/_damon_sysfs.py
index 1e587e0b1a3956e9f7df6948dd519c350605bbf4..5b1cb6b3ce4e2fe8b4f3ec9ec4f26387130827f3 100644 (file)
--- a/tools/testing/selftests/damon/_damon_sysfs.py
+++ b/tools/testing/selftests/damon/_damon_sysfs.py
@@ -15,6 +15,10 @@ if sysfs_root is None:
     print('Seems sysfs not mounted?')
     exit(ksft_skip)
 
+if not os.path.exists(sysfs_root):
+    print('Seems DAMON disabled?')
+    exit(ksft_skip)
+
 def write_file(path, string):
     "Returns error string if failed, or None otherwise"
     string = '%s' % string