From 4d96b4635aeff1b8ad41d41422ce808ce0b971c8 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Sat, 1 Feb 2020 02:30:25 +0100 Subject: bpo-39511: PyThreadState_Clear() calls on_delete (GH-18296) PyThreadState.on_delete is a callback used to notify Python when a thread completes. _thread._set_sentinel() function creates a lock which is released when the thread completes. It sets on_delete callback to the internal release_sentinel() function. This lock is known as Threading._tstate_lock in the threading module. The release_sentinel() function uses the Python C API. The problem is that on_delete is called late in the Python finalization, when the C API is no longer fully working. The PyThreadState_Clear() function now calls the PyThreadState.on_delete callback. Previously, that happened in PyThreadState_Delete(). The release_sentinel() function is now called when the C API is still fully working. --- Python/pystate.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'Python/pystate.c') diff --git a/Python/pystate.c b/Python/pystate.c index d792380de4..ebc17ea5a7 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -806,6 +806,10 @@ PyThreadState_Clear(PyThreadState *tstate) Py_CLEAR(tstate->async_gen_finalizer); Py_CLEAR(tstate->context); + + if (tstate->on_delete != NULL) { + tstate->on_delete(tstate->on_delete_data); + } } @@ -830,9 +834,7 @@ tstate_delete_common(PyThreadState *tstate, if (tstate->next) tstate->next->prev = tstate->prev; HEAD_UNLOCK(runtime); - if (tstate->on_delete != NULL) { - tstate->on_delete(tstate->on_delete_data); - } + PyMem_RawFree(tstate); if (gilstate->autoInterpreterState && -- cgit v1.2.1