Remove global logging mutex

Reverts most of #562

ros2/rclcpp#1042 describes a crash that can occur in rclcpp when rcl
logging functions are called in different threads. This was fixed in
ros2/rclcpp#1125, and a similar fix was made for rclpy in #562.

This fix is unnecessary in rclpy because it cannot call the logging
macros from multiple threads unless the GIL is released. The only place
the GIL is released is around rcl_wait(), so the logging methods are
already protected.

Removing this code makes it a little easier to divide the remaining work
of porting _rclpy.c to pybind11. If for some reason we decide to release
the GIL around logging methods in the future, then they can be protected
in the future using `pybind11::call_guard<T>` with a type that locks a
global logging mutex when it is default constructed and unlocks it when
its destructed.

Signed-off-by: Shane Loretz <sloretz@openrobotics.org>
Signed-off-by: Shane Loretz <sloretz@osrfoundation.org>

rclpy/CMakeLists.txt

@@ -154,9 +154,6 @@ install(TARGETS rclpy_common
 # Main extension with bulk of the code
 pybind11_add_module(_rclpy SHARED
   src/rclpy/_rclpy.c
-  src/rclpy/detail/execute_with_logging_mutex.cpp
-  src/rclpy/detail/logging_mutex.cpp
-  src/rclpy/detail/thread_safe_logging_output_handler.cpp
 )
 target_link_libraries(_rclpy PRIVATE
   rclpy_common

rclpy/src/rclpy/_rclpy.c

@@ -45,8 +45,6 @@
 #include <rmw/validate_node_name.h>
 #include <rosidl_runtime_c/message_type_support_struct.h>
 
-#include "./detail/thread_safe_logging_output_handler.h"
-#include "./detail/execute_with_logging_mutex.h"
 #include "rclpy_common/common.h"
 #include "rclpy_common/handle.h"
 
@@ -529,7 +527,7 @@ rclpy_init(PyObject * module, PyObject * args)
  * Raises RuntimeError if rcl logging could not be initialized
  */
 static PyObject *
-rclpy_logging_configure_impl(PyObject * module, PyObject * args)
+rclpy_logging_configure(PyObject * module, PyObject * args)
 {
   rclpy_module_state_t * module_state = (rclpy_module_state_t *)PyModule_GetState(module);
   if (!module_state) {
@@ -547,10 +545,8 @@ rclpy_logging_configure_impl(PyObject * module, PyObject * args)
     return NULL;
   }
   rcl_allocator_t allocator = rcl_get_default_allocator();
-  rcl_ret_t ret = rcl_logging_configure_with_output_handler(
-    &context->global_arguments,
-    &allocator,
-    rclpy_detail_thread_safe_logging_output_handler);
+  rcl_ret_t ret = rcl_logging_configure(
+    &context->global_arguments, &allocator);
   if (RCL_RET_OK != ret) {
     PyErr_Format(
       module_state->RCLError,
@@ -561,19 +557,12 @@ rclpy_logging_configure_impl(PyObject * module, PyObject * args)
   Py_RETURN_NONE;
 }
 
-/// See rclpy_logging_configure_impl above.
-static PyObject *
-rclpy_logging_configure(PyObject * self, PyObject * args)
-{
-  return rclpy_detail_execute_with_logging_mutex(rclpy_logging_configure_impl, self, args);
-}
-
 /// Finalize rcl logging
 /**
  * Produces a RuntimeWarning if rcl logging could not be finalized
  */
 static PyObject *
-rclpy_logging_fini_impl(PyObject * Py_UNUSED(self), PyObject * Py_UNUSED(args))
+rclpy_logging_fini(PyObject * Py_UNUSED(self), PyObject * Py_UNUSED(args))
 {
   rcl_ret_t ret = rcl_logging_fini();
   if (RCL_RET_OK != ret) {
@@ -589,16 +578,9 @@ rclpy_logging_fini_impl(PyObject * Py_UNUSED(self), PyObject * Py_UNUSED(args))
   Py_RETURN_NONE;
 }
 
-/// See rclpy_logging_fini_impl above.
-static PyObject *
-rclpy_logging_fini(PyObject * self, PyObject * args)
-{
-  return rclpy_detail_execute_with_logging_mutex(rclpy_logging_fini_impl, self, args);
-}
-
 /// Handle destructor for node
 static void
-_rclpy_destroy_node_impl(void * p)
+_rclpy_destroy_node(void * p)
 {
   rcl_node_t * node = p;
   if (!node) {
@@ -620,13 +602,6 @@ _rclpy_destroy_node_impl(void * p)
   PyMem_Free(node);
 }
 
-/// See _rclpy_destroy_node_impl above.
-static void
-_rclpy_destroy_node(void * p)
-{
-  rclpy_detail_execute_with_logging_mutex2(_rclpy_destroy_node_impl, p);
-}
-
 /// Create a node
 /**
  * Raises ValueError if the node name or namespace is invalid
@@ -639,7 +614,7 @@ _rclpy_destroy_node(void * p)
  * \return NULL on failure
  */
 static PyObject *
-rclpy_create_node_impl(PyObject * module, PyObject * args)
+rclpy_create_node(PyObject * module, PyObject * args)
 {
   rcl_ret_t ret;
   const char * node_name;
@@ -752,13 +727,6 @@ rclpy_create_node_impl(PyObject * module, PyObject * args)
   return node_capsule;
 }
 
-/// See rclpy_create_node_impl above.
-static PyObject *
-rclpy_create_node(PyObject * self, PyObject * args)
-{
-  return rclpy_detail_execute_with_logging_mutex(rclpy_create_node_impl, self, args);
-}
-
 /// Get the name of a node.
 /**
  * Raises ValueError if pynode is not a node capsule