From a9d7e552c72b6e9515e76a1dd4b247da86da23de Mon Sep 17 00:00:00 2001 From: Yury Selivanov Date: Tue, 19 Dec 2017 07:18:45 -0500 Subject: [PATCH] bpo-32357: Optimize asyncio.iscoroutine() for non-native coroutines (#4915) --- Lib/asyncio/coroutines.py | 21 +++- Lib/test/test_asyncio/test_tasks.py | 43 +++++++ .../2017-12-18-00-36-41.bpo-32357.t1F3sn.rst | 5 + Modules/_asynciomodule.c | 113 +++++++++++++----- 4 files changed, 149 insertions(+), 33 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2017-12-18-00-36-41.bpo-32357.t1F3sn.rst diff --git a/Lib/asyncio/coroutines.py b/Lib/asyncio/coroutines.py index e3c0162dd14..9c860a452b5 100644 --- a/Lib/asyncio/coroutines.py +++ b/Lib/asyncio/coroutines.py @@ -1,5 +1,6 @@ __all__ = 'coroutine', 'iscoroutinefunction', 'iscoroutine' +import collections.abc import functools import inspect import os @@ -7,8 +8,6 @@ import sys import traceback import types -from collections.abc import Awaitable, Coroutine - from . import base_futures from . import constants from . import format_helpers @@ -162,7 +161,7 @@ def coroutine(func): except AttributeError: pass else: - if isinstance(res, Awaitable): + if isinstance(res, collections.abc.Awaitable): res = yield from await_meth() return res @@ -199,12 +198,24 @@ def iscoroutinefunction(func): # Prioritize native coroutine check to speed-up # asyncio.iscoroutine. _COROUTINE_TYPES = (types.CoroutineType, types.GeneratorType, - Coroutine, CoroWrapper) + collections.abc.Coroutine, CoroWrapper) +_iscoroutine_typecache = set() def iscoroutine(obj): """Return True if obj is a coroutine object.""" - return isinstance(obj, _COROUTINE_TYPES) + if type(obj) in _iscoroutine_typecache: + return True + + if isinstance(obj, _COROUTINE_TYPES): + # Just in case we don't want to cache more than 100 + # positive types. That shouldn't ever happen, unless + # someone stressing the system on purpose. + if len(_iscoroutine_typecache) < 100: + _iscoroutine_typecache.add(type(obj)) + return True + else: + return False def _format_coroutine(coro): diff --git a/Lib/test/test_asyncio/test_tasks.py b/Lib/test/test_asyncio/test_tasks.py index 47206613993..f1dbb99d4fc 100644 --- a/Lib/test/test_asyncio/test_tasks.py +++ b/Lib/test/test_asyncio/test_tasks.py @@ -62,6 +62,20 @@ class Dummy: pass +class CoroLikeObject: + def send(self, v): + raise StopIteration(42) + + def throw(self, *exc): + pass + + def close(self): + pass + + def __await__(self): + return self + + class BaseTaskTests: Task = None @@ -2085,6 +2099,12 @@ class BaseTaskTests: "a coroutine was expected, got 123"): self.new_task(self.loop, 123) + # test it for the second time to ensure that caching + # in asyncio.iscoroutine() doesn't break things. + with self.assertRaisesRegex(TypeError, + "a coroutine was expected, got 123"): + self.new_task(self.loop, 123) + def test_create_task_with_oldstyle_coroutine(self): @asyncio.coroutine @@ -2095,6 +2115,12 @@ class BaseTaskTests: self.assertIsInstance(task, self.Task) self.loop.run_until_complete(task) + # test it for the second time to ensure that caching + # in asyncio.iscoroutine() doesn't break things. + task = self.new_task(self.loop, coro()) + self.assertIsInstance(task, self.Task) + self.loop.run_until_complete(task) + def test_create_task_with_async_function(self): async def coro(): @@ -2104,6 +2130,23 @@ class BaseTaskTests: self.assertIsInstance(task, self.Task) self.loop.run_until_complete(task) + # test it for the second time to ensure that caching + # in asyncio.iscoroutine() doesn't break things. + task = self.new_task(self.loop, coro()) + self.assertIsInstance(task, self.Task) + self.loop.run_until_complete(task) + + def test_create_task_with_asynclike_function(self): + task = self.new_task(self.loop, CoroLikeObject()) + self.assertIsInstance(task, self.Task) + self.assertEqual(self.loop.run_until_complete(task), 42) + + # test it for the second time to ensure that caching + # in asyncio.iscoroutine() doesn't break things. + task = self.new_task(self.loop, CoroLikeObject()) + self.assertIsInstance(task, self.Task) + self.assertEqual(self.loop.run_until_complete(task), 42) + def test_bare_create_task(self): async def inner(): diff --git a/Misc/NEWS.d/next/Library/2017-12-18-00-36-41.bpo-32357.t1F3sn.rst b/Misc/NEWS.d/next/Library/2017-12-18-00-36-41.bpo-32357.t1F3sn.rst new file mode 100644 index 00000000000..f51eaf541dc --- /dev/null +++ b/Misc/NEWS.d/next/Library/2017-12-18-00-36-41.bpo-32357.t1F3sn.rst @@ -0,0 +1,5 @@ +Optimize asyncio.iscoroutine() and loop.create_task() for non-native +coroutines (e.g. async/await compiled with Cython). + +'loop.create_task(python_coroutine)' used to be 20% faster than +'loop.create_task(cython_coroutine)'. Now, the latter is as fast. diff --git a/Modules/_asynciomodule.c b/Modules/_asynciomodule.c index 5030a40b873..33ae067de4b 100644 --- a/Modules/_asynciomodule.c +++ b/Modules/_asynciomodule.c @@ -49,6 +49,9 @@ static PyObject *current_tasks; all running event loops. {EventLoop: Task} */ static PyObject *all_tasks; +/* An isinstance type cache for the 'is_coroutine()' function. */ +static PyObject *iscoroutine_typecache; + typedef enum { STATE_PENDING, @@ -118,6 +121,71 @@ static PyObject* future_new_iter(PyObject *); static inline int future_call_schedule_callbacks(FutureObj *); +static int +_is_coroutine(PyObject *coro) +{ + /* 'coro' is not a native coroutine, call asyncio.iscoroutine() + to check if it's another coroutine flavour. + + Do this check after 'future_init()'; in case we need to raise + an error, __del__ needs a properly initialized object. + */ + PyObject *res = PyObject_CallFunctionObjArgs( + asyncio_iscoroutine_func, coro, NULL); + if (res == NULL) { + return -1; + } + + int is_res_true = PyObject_IsTrue(res); + Py_DECREF(res); + if (is_res_true <= 0) { + return is_res_true; + } + + if (PySet_Size(iscoroutine_typecache) < 100) { + /* Just in case we don't want to cache more than 100 + positive types. That shouldn't ever happen, unless + someone stressing the system on purpose. + */ + if (PySet_Add(iscoroutine_typecache, (PyObject*) Py_TYPE(coro))) { + return -1; + } + } + + return 1; +} + + +static inline int +is_coroutine(PyObject *coro) +{ + if (PyCoro_CheckExact(coro)) { + return 1; + } + + /* Check if `type(coro)` is in the cache. + Caching makes is_coroutine() function almost as fast as + PyCoro_CheckExact() for non-native coroutine-like objects + (like coroutines compiled with Cython). + + asyncio.iscoroutine() has its own type caching mechanism. + This cache allows us to avoid the cost of even calling + a pure-Python function in 99.9% cases. + */ + int has_it = PySet_Contains( + iscoroutine_typecache, (PyObject*) Py_TYPE(coro)); + if (has_it == 0) { + /* type(coro) is not in iscoroutine_typecache */ + return _is_coroutine(coro); + } + + /* either an error has occured or + type(coro) is in iscoroutine_typecache + */ + return has_it; +} + + static int get_running_loop(PyObject **loop) { @@ -1778,37 +1846,20 @@ static int _asyncio_Task___init___impl(TaskObj *self, PyObject *coro, PyObject *loop) /*[clinic end generated code: output=9f24774c2287fc2f input=8d132974b049593e]*/ { - PyObject *res; - if (future_init((FutureObj*)self, loop)) { return -1; } - if (!PyCoro_CheckExact(coro)) { - /* 'coro' is not a native coroutine, call asyncio.iscoroutine() - to check if it's another coroutine flavour. - - Do this check after 'future_init()'; in case we need to raise - an error, __del__ needs a properly initialized object. - */ - res = PyObject_CallFunctionObjArgs( - asyncio_iscoroutine_func, coro, NULL); - if (res == NULL) { - return -1; - } - - int tmp = PyObject_Not(res); - Py_DECREF(res); - if (tmp < 0) { - return -1; - } - if (tmp) { - self->task_log_destroy_pending = 0; - PyErr_Format(PyExc_TypeError, - "a coroutine was expected, got %R", - coro, NULL); - return -1; - } + int is_coro = is_coroutine(coro); + if (is_coro == -1) { + return -1; + } + if (is_coro == 0) { + self->task_log_destroy_pending = 0; + PyErr_Format(PyExc_TypeError, + "a coroutine was expected, got %R", + coro, NULL); + return -1; } self->task_fut_waiter = NULL; @@ -3007,8 +3058,9 @@ module_free(void *m) Py_CLEAR(asyncio_InvalidStateError); Py_CLEAR(asyncio_CancelledError); - Py_CLEAR(current_tasks); Py_CLEAR(all_tasks); + Py_CLEAR(current_tasks); + Py_CLEAR(iscoroutine_typecache); module_free_freelists(); } @@ -3028,6 +3080,11 @@ module_init(void) goto fail; } + iscoroutine_typecache = PySet_New(NULL); + if (iscoroutine_typecache == NULL) { + goto fail; + } + #define WITH_MOD(NAME) \ Py_CLEAR(module); \ module = PyImport_ImportModule(NAME); \