DISPATCH-1962 Fix leak of IoAdapter_init

Author: jiridanek

src/dispatch.c

@@ -341,6 +341,7 @@ qd_error_t qd_dispatch_prepare(qd_dispatch_t *qd)
 void qd_dispatch_set_agent(qd_dispatch_t *qd, void *agent) {
     assert(agent);
     assert(!qd->agent);
+    Py_IncRef(agent);
     qd->agent = agent;
 }
 

src/python_embedded.c

@@ -562,7 +562,8 @@ static PyTypeObject LogAdapterType = {
     .tp_dealloc   = (destructor)LogAdapter_dealloc,
     .tp_flags     = Py_TPFLAGS_DEFAULT,
     .tp_methods   = LogAdapter_methods,
-    .tp_init      = (initproc)LogAdapter_init
+    .tp_init      = (initproc)LogAdapter_init,
+    .tp_new       = PyType_GenericNew,
 };
 
 
@@ -716,10 +717,24 @@ static int IoAdapter_init(IoAdapter *self, PyObject *args, PyObject *kwds)
     return 0;
 }
 
+// visit all members which may conceivably participate in reference cycles
+static int IoAdapter_traverse(IoAdapter* self, visitproc visit, void *arg)
+{
+    Py_VISIT(self->handler);
+    return 0;
+}
+
+static int IoAdapter_clear(IoAdapter* self)
+{
+    Py_CLEAR(self->handler);
+    return 0;
+}
+
 static void IoAdapter_dealloc(IoAdapter* self)
 {
     qdr_core_unsubscribe(self->sub);
-    Py_DECREF(self->handler);
+    PyObject_GC_UnTrack(self);
+    IoAdapter_clear(self);
     Py_TYPE(self)->tp_free((PyObject*)self);
 }
 
@@ -812,10 +827,13 @@ static PyTypeObject IoAdapterType = {
     .tp_name      = DISPATCH_MODULE ".IoAdapter",
     .tp_doc       = "Dispatch IO Adapter",
     .tp_basicsize = sizeof(IoAdapter),
+    .tp_traverse  = (traverseproc)IoAdapter_traverse,
+    .tp_clear     = (inquiry)IoAdapter_clear,
     .tp_dealloc   = (destructor)IoAdapter_dealloc,
-    .tp_flags     = Py_TPFLAGS_DEFAULT,
+    .tp_flags     = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,
     .tp_methods   = IoAdapter_methods,
     .tp_init      = (initproc)IoAdapter_init,
+    .tp_new       = PyType_GenericNew,
 };
 
 
@@ -831,8 +849,6 @@ static void qd_register_constant(PyObject *module, const char *name, uint32_t va
 
 static void qd_python_setup(void)
 {
-    LogAdapterType.tp_new = PyType_GenericNew;
-    IoAdapterType.tp_new  = PyType_GenericNew;
     if ((PyType_Ready(&LogAdapterType) < 0) || (PyType_Ready(&IoAdapterType) < 0)) {
         qd_error_py();
         qd_log(log_source, QD_LOG_CRITICAL, "Unable to initialize Adapters");

src/router_node.c

@@ -2153,12 +2153,12 @@ void qd_router_free(qd_router_t *router)
 
     qd_container_set_default_node_type(router->qd, 0, 0, QD_DIST_BOTH);
 
+    qd_router_python_free(router);
     qdr_core_free(router->router_core);
     qd_tracemask_free(router->tracemask);
     qd_timer_free(router->timer);
     sys_mutex_free(router->lock);
     qd_router_configure_free(router);
-    qd_router_python_free(router);
 
     free(router);
     free(node_id);

src/router_pynode.c

@@ -444,6 +444,7 @@ qd_error_t qd_router_python_setup(qd_router_t *router)
     // Instantiate the router
     //
     pyRouter = PyObject_CallObject(pClass, pArgs);
+    Py_DECREF(pClass);
     Py_DECREF(pArgs);
     Py_DECREF(adapterType);
     QD_ERROR_PY_RET();
@@ -456,7 +457,12 @@ qd_error_t qd_router_python_setup(qd_router_t *router)
 }
 
 void qd_router_python_free(qd_router_t *router) {
-    // empty
+    Py_XDECREF(pyRouter);
+    Py_XDECREF(pyTick);
+    Py_XDECREF(pySetMobileSeq);
+    Py_XDECREF(pySetMyMobileSeq);
+    Py_XDECREF(pyLinkLost);
+    PyGC_Collect();
 }
 
 

tests/lsan.supp

@@ -2,9 +2,6 @@
 # found by AddressSanitizer (ASAN)
 #
 
-# to be triaged; pretty much all tests
-leak:^IoAdapter_init$
-
 # to be triaged; pretty much all tests
 leak:^load_server_config$
 leak:^qd_dispatch_configure_connector$
@@ -36,10 +33,6 @@ leak:^pni_init_default_logger$
 # DISPATCH-1844 - shutdown leak
 leak:sys_mutex
 
-# expected, not a bug:
-#
-leak:qdr_core_subscribe
-
 # Ubuntu 16.04 (Xenial)
 #
 leak:_ctypes_alloc_format_string