ftests: Add test to delete cgroup on shared mount point

The user might try to delete the cgroup created on a mount point shared
by cgroup v1 controllers, once for each controller.  This functional
test emulates the deletion behavior and expects the test to pass without
complaint about missing directory, when attempted to delete on the
second controller.

-----------------------------------------------------------------
Test Results:
        Run Date:                          Apr 23 06:44:27
        Passed:                                  1 test(s)
        Skipped:                                 0 test(s)
        Failed:                                  0 test(s)
-----------------------------------------------------------------
Timing Results:
        Test                                       Time (sec)
        -----------------------------------------------------
        setup                                            0.00
        047-cgcreate-delete_cgrp_shared_mnt.py           0.03
        teardown                                         0.00
        -----------------------------------------------------

Signed-off-by: Kamalesh Babulal <kamalesh.babulal@oracle.com>
Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>

diff --git a/ftests/047-cgcreate-delete_cgrp_shared_mnt.py b/ftests/047-cgcreate-delete_cgrp_shared_mnt.py
new file mode 100755 (executable)
index 0000000..1d5e59c
--- /dev/null
+++ b/ftests/047-cgcreate-delete_cgrp_shared_mnt.py
@@ -0,0 +1,93 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: LGPL-2.1-only
+#
+# Test deleting cgroup on mount point shared by cgroup v1 controllers
+#
+# Copyright (c) 2022 Oracle and/or its affiliates.
+# Author: Kamalesh Babulal <kamalesh.babulal@oracle.com>
+#
+
+from cgroup import Cgroup, CgroupVersion
+from run import RunError
+import consts
+import ftests
+import sys
+import os
+
+CONTROLLER1 = 'cpu'
+CONTROLLER2 = 'cpuacct'
+
+CGNAME = '047shared_mnts'
+
+
+def prereqs(config):
+    result = consts.TEST_PASSED
+    cause = None
+
+    if CgroupVersion.get_version('cpu') != CgroupVersion.CGROUP_V1:
+        result = consts.TEST_SKIPPED
+        cause = 'This test requires the cgroup v1 cpu controller'
+
+    # cpuacct controller is only available on cgroup v1, if an exception
+    # gets raised, then no cgroup v1 controllers mounted.
+    try:
+        CgroupVersion.get_version('cpuacct')
+    except IndexError:
+        result = consts.TEST_SKIPPED
+        cause = 'This test requires the cgroup v1 cpuacct controller'
+
+    return result, cause
+
+
+def setup(config):
+    Cgroup.create(config, CONTROLLER1, CGNAME)
+
+
+def test(config):
+    result = consts.TEST_PASSED
+    cause = None
+
+    try:
+        Cgroup.delete(config, CONTROLLER2, CGNAME)
+    except RunError as re:
+        if 'No such file or directory' in re.stderr:
+            cause = 'cpu and cpuacct controllers do not share mount points.'
+            result = consts.TEST_FAILED
+        else:
+            raise re
+
+    try:
+        Cgroup.delete(config, CONTROLLER1, CGNAME)
+    except RunError as re:
+        if 'No such file or directory' in re.stderr:
+            cause = 'Missing support to delete cgroup on shared mount points.'
+            result = consts.TEST_FAILED
+        else:
+            raise re
+
+    return result, cause
+
+
+def teardown(config):
+    return consts.TEST_PASSED, None
+
+
+def main(config):
+    [result, cause] = prereqs(config)
+    if result != consts.TEST_PASSED:
+        return [result, cause]
+
+    setup(config)
+    [result, cause] = test(config)
+    teardown(config)
+
+    return [result, cause]
+
+
+if __name__ == '__main__':
+    config = ftests.parse_args()
+    # this test was invoked directly.  run only it
+    config.args.num = int(os.path.basename(__file__).split('-')[0])
+    sys.exit(ftests.main(config))
+
+# vim: set et ts=4 sw=4: