kernfs,memcg: Add test case for memcg helpers.

Orabug: 37322867
Signed-off-by: Imran Khan <[email protected]>

tests/test_kernfs_memcg.py

@@ -0,0 +1,33 @@
+# Copyright (c) 2024, Oracle and/or its affiliates.
+# Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
+import drgn
+
+from drgn_tools import kernfs_memcg as kernfs_memcg
+
+
+def test_dump_page_cache_pages_pinning_cgroups(prog: drgn.Program) -> None:
+    kernfs_memcg.dump_page_cache_pages_pinning_cgroups(prog, 10)
+
+
+def test_dump_memcgroup_hierarchy(prog: drgn.Program) -> None:
+    kernfs_memcg.dump_memcgroup_hierarchy(prog)
+
+
+def test_kernfs_node_of_memcgroup(prog: drgn.Program) -> None:
+    count = 0
+    for kn in kernfs_memcg.for_each_kernfs_node(prog):
+        if kernfs_memcg.kernfs_node_of_memcgroup(kn):
+            count = count + 1
+        if count >= 5:
+            print("Found 5 memcgroup, kernfs_node objects.")
+            break
+
+
+def test_get_num_active_mem_cgroups(prog: drgn.Program) -> None:
+    count = kernfs_memcg.get_num_active_mem_cgroups(prog)
+    print(f"number of active memcgroups: {count}\n")
+
+
+def test_get_num_dying_mem_cgroups(prog: drgn.Program) -> None:
+    count = kernfs_memcg.get_num_dying_mem_cgroups(prog)
+    print(f"number of dying memcgroups: {count}\n")