ftests/092: add test to attach threads to cgroup (v1)

Add test to attach/move all thread of a tid to cgroup using
cgroup_attach_thread_tid() in cgroup v1.

-----------------------------------------------------------------
Test Results:
        Run Date:                          Mar 13 09:52:58
        Passed:                                  1 test(s)
        Skipped:                                 0 test(s)
        Failed:                                  0 test(s)
-----------------------------------------------------------------
Timing Results:
        Test                                     Time (sec)
        ---------------------------------------------------
        setup                                          0.00
        092-sudo-cgroup_attach_thread_tid.py           0.09
        teardown                                       0.00
        ---------------------------------------------------
        Total Run Time                                 0.09

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

diff --git a/tests/ftests/092-sudo-cgroup_attach_thread_tid.py b/tests/ftests/092-sudo-cgroup_attach_thread_tid.py
new file mode 100755 (executable)
index 0000000..ee1ee84
--- /dev/null
+++ b/tests/ftests/092-sudo-cgroup_attach_thread_tid.py
@@ -0,0 +1,130 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: LGPL-2.1-only
+#
+# Attach a task to a cgroup via cgroup_attach_thread_tid()
+#
+# Copyright (c) 2024 Oracle and/or its affiliates.
+# Author: Kamalesh Babulal <kamalesh.babulal@oracle.com>
+#
+
+from cgroup import Cgroup as CgroupCli
+from libcgroup import Cgroup, Version
+from cgroup import CgroupVersion
+from process import Process
+import ftests
+import consts
+import sys
+import os
+
+CGNAME1 = '092cgattachcg1'
+CGNAME2 = '092cgattachcg2'
+CONTROLLER = 'cpu'
+THREADS = 3
+
+
+def prereqs(config):
+    result = consts.TEST_PASSED
+    cause = None
+
+    if config.args.container:
+        result = consts.TEST_SKIPPED
+        cause = 'This test cannot be run within a container'
+        return result, cause
+
+    if CgroupVersion.get_version(CONTROLLER) != CgroupVersion.CGROUP_V1:
+        result = consts.TEST_SKIPPED
+        cause = 'This test requires cgroup v1'
+
+    return result, cause
+
+
+def setup(config):
+    cg = Cgroup(CGNAME1, Version.CGROUP_V1)
+    cg.add_controller(CONTROLLER)
+    cg.create()
+
+    cg = Cgroup(CGNAME2, Version.CGROUP_V1)
+    cg.add_controller(CONTROLLER)
+    cg.create()
+
+
+def read_cgroup_tasks_file(config, CONTROLLER, CGNAME):
+    mnt_path = CgroupCli.get_controller_mount_point(CONTROLLER)
+    path = os.path.join(mnt_path, CGNAME, "tasks")
+
+    cgrp_pids = [line.strip() for line in open(path, 'r')]
+    return cgrp_pids
+
+
+def test(config):
+    result = consts.TEST_PASSED
+    cause = None
+
+    config.process.create_threaded_process_in_cgroup(config, CONTROLLER, CGNAME1, THREADS)
+
+    threads_tid_cg1 = read_cgroup_tasks_file(config, CONTROLLER, CGNAME1)
+    if len(threads_tid_cg1) == 0:
+        result = consts.TEST_FAILED
+        cause = 'No threads found in cgroup {}'.format(CGNAME1)
+        return result, cause
+
+    cg = Cgroup(CGNAME2, Version.CGROUP_V1)
+    cg.add_controller(CONTROLLER)
+    cg.attach(int(threads_tid_cg1[0]), attach_threads=True)
+
+    threads_tid_cg2 = read_cgroup_tasks_file(config, CONTROLLER, CGNAME2)
+    if len(threads_tid_cg2) == 0:
+        result = consts.TEST_FAILED
+        cause = 'Thread attach from cgroup {} to {}, failed'.format(CGNAME1, CGNAME2)
+        return result, cause
+
+    threads_tid_cg1.sort()
+    threads_tid_cg2.sort()
+
+    if threads_tid_cg1 != threads_tid_cg2:
+        result = consts.TEST_FAILED
+        cause = 'Not all threads have moved from cgroup {} to {}'. format(CGNAME1, CGNAME2)
+        return result, cause
+
+    threads_tid_cg1 = read_cgroup_tasks_file(config, CONTROLLER, CGNAME1)
+    if len(threads_tid_cg1) != 0:
+        result = consts.TEST_FAILED
+        cause = 'Threads found in cgroup {} expected none'.format(CGNAME1)
+
+    return result, cause
+
+
+def teardown(config, result):
+    # Incase the migration fails, kill the process in CGNAME1
+    pids = CgroupCli.get_pids_in_cgroup(config, CGNAME1, CONTROLLER)
+    Process.kill(config, pids)
+
+    pids = CgroupCli.get_pids_in_cgroup(config, CGNAME2, CONTROLLER)
+    Process.kill(config, pids)
+
+    CgroupCli.delete(config, CONTROLLER, CGNAME1)
+    CgroupCli.delete(config, CONTROLLER, CGNAME2)
+
+
+def main(config):
+    [result, cause] = prereqs(config)
+    if result != consts.TEST_PASSED:
+        return [result, cause]
+
+    try:
+        result = consts.TEST_FAILED
+        setup(config)
+        [result, cause] = test(config)
+    finally:
+        teardown(config, result)
+
+    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: