replace storing the task counter on task construction with just getti…

…ng the next counter at lazy name generation
python · gvanrossum · Apr 29, 2023 · Apr 24, 2023 · Apr 24, 2023 · Apr 24, 2023
commit 2efd376a739946c5fd9d2902f04634f21763c9a7
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py
@@ -103,9 +103,8 @@ def __init__(self, coro, *, loop=None, name=None, context=None):
            self._log_destroy_pending = False
            raise TypeError(f"a coroutine was expected, got {coro!r}")

-        self._task_name_counter = 0
        if name is None:
-            self._task_name_counter = _task_name_counter()
+            # optimization: defer task name formatting to first get_name
            self._name = None
        else:
            self._name = str(name)
@@ -146,7 +145,7 @@ def get_context(self):

    def get_name(self):
        if self._name is None:
-            self._name = f'Task-{self._task_name_counter}'
+            self._name = f'Task-{_task_name_counter()}'
        return self._name

    def set_name(self, value):

@@ -129,7 +129,6 @@ typedef struct {
    int task_must_cancel;
    int task_log_destroy_pending;
    int task_num_cancels_requested;
-    uint64_t task_name_counter;
 } TaskObj;

 typedef struct {
@@ -2066,16 +2065,13 @@ _asyncio_Task___init___impl(TaskObj *self, PyObject *coro, PyObject *loop,
    self->task_must_cancel = 0;
    self->task_log_destroy_pending = 1;
    self->task_num_cancels_requested = 0;
-    self->task_name_counter = 0;
    Py_INCREF(coro);
    Py_XSETREF(self->task_coro, coro);

    if (name == Py_None) {
        // optimization: defer task name formatting
-        // set task_name to None to indicate deferred formatting, and
-        // store the task name counter for formatting in get_name impl
+        // set task_name to None to indicate deferred formatting
        Py_INCREF(name);
-        self->task_name_counter = ++state->task_name_counter;
    } else if (!PyUnicode_CheckExact(name)) {
        name = PyObject_Str(name);
    } else {
@@ -2455,9 +2451,9 @@ _asyncio_Task_get_name_impl(TaskObj *self)
 {
    if (self->task_name) {
        if (Py_IsNone(self->task_name)) {
-            assert(self->task_name_counter > 0);
+            asyncio_state *state = get_asyncio_state_by_def((PyObject *)self);
            PyObject *name = PyUnicode_FromFormat(
-                "Task-%" PRIu64, self->task_name_counter);
+                "Task-%" PRIu64, ++state->task_name_counter);
            Py_XSETREF(self->task_name, name);
            return Py_NewRef(self->task_name);
        }