Rename from _Py_INTERNAL_ABI_SLOT to _Py_ABI_SLOT
and define the macro using _PyABIInfo_DEFAULT.
Use the ABI slot in stdlib extension modules to enable running
a check of ABI version compatibility.
_tkinter, _tracemalloc and readline don't use the slots, hence they need
explicit handling.
Co-authored-by: Victor Stinner <vstinner@python.org>
Optimize `asyncio.all_tasks()` for the common case where the event loop is running in the current thread by avoiding stop-the-world pauses and locking.
This optimization is already present for `asyncio.current_task()` so we do the same for `asyncio.all_tasks()`.
To avoid having the debug sections being optimised away by the compiler
we use __attribute__((used)) on gcc and clang but in Windows this is
not supported by the Microsoft compiler and there is no equivalent flag.
Unfortunately Windows offers almost no alternative other than exporting
the symbol in the dynamic table or using it somehow.
Store the current running task on the thread state, it makes it thread safe for the free-threading build and while improving performance as there is no lock contention, this effectively makes it lock free.
When accessing the current task of the current running loop in current thread, no locking is required and can be acessed without locking.
In the rare case of accessing current task of a loop running in a different thread, the stop the world pauses is used in free-threading builds to stop all other running threads and find the task for the specified loop.
This also makes it easier for external introspection to find the current task, and now it will be always correct.
This was missing from gh-124640. It's already covered by the new
test_asyncio/test_free_threading.py in combination with the runtime
assertion in set_ts_asyncio_running_task.
Co-authored-by: Kumar Aditya <kumaraditya@python.org>
* Makes `_asyncio.Task` and `_asyncio.Future` thread-safe by adding critical sections
* Add assertions to check for thread safety checking locking of object by critical sections in internal functions
* Make `_asyncio.all_tasks` thread safe when eager tasks are used
* Add a thread safety test
Fix `asyncio.Future._callbacks` to always return a copy of the internal list of callbacks to avoid mutation from user code affecting the internal state.
Switch more _Py_IsImmortal(...) assertions to _Py_IsImmortalLoose(...)
The remaining calls to _Py_IsImmortal are in free-threaded-only code,
initialization of core objects, tests, and guards that fall back to
code that works with mortal objects.