From b36e5d627d4232a01850707eb78a5067f3fd77f4 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Mon, 29 Apr 2019 11:15:56 +0200 Subject: bpo-36356: Destroy the GIL at exit (GH-12453) * Add _PyEval_FiniThreads2(). _PyEval_FiniThreads() now only clears the pending lock, whereas _PyEval_FiniThreads2() destroys the GIL. * pymain_free() now calls _PyEval_FiniThreads2(). * Py_FinalizeEx() now calls _PyEval_FiniThreads(). --- Include/ceval.h | 3 --- Include/internal/pycore_ceval.h | 3 +++ Modules/main.c | 11 ++++++----- Python/ceval.c | 16 +++++++++++----- Python/pylifecycle.c | 11 ++++++----- 5 files changed, 26 insertions(+), 18 deletions(-) diff --git a/Include/ceval.h b/Include/ceval.h index 11283c0..98e873d 100644 --- a/Include/ceval.h +++ b/Include/ceval.h @@ -192,9 +192,6 @@ PyAPI_FUNC(void) PyEval_RestoreThread(PyThreadState *); PyAPI_FUNC(int) PyEval_ThreadsInitialized(void); PyAPI_FUNC(void) PyEval_InitThreads(void); -#ifndef Py_LIMITED_API -PyAPI_FUNC(void) _PyEval_FiniThreads(void); -#endif /* !Py_LIMITED_API */ PyAPI_FUNC(void) PyEval_AcquireLock(void) Py_DEPRECATED(3.2); PyAPI_FUNC(void) PyEval_ReleaseLock(void) /* Py_DEPRECATED(3.2) */; PyAPI_FUNC(void) PyEval_AcquireThread(PyThreadState *tstate); diff --git a/Include/internal/pycore_ceval.h b/Include/internal/pycore_ceval.h index 0bb19f1..ae3d832 100644 --- a/Include/internal/pycore_ceval.h +++ b/Include/internal/pycore_ceval.h @@ -54,6 +54,9 @@ struct _ceval_runtime_state { PyAPI_FUNC(void) _PyEval_Initialize(struct _ceval_runtime_state *); +PyAPI_FUNC(void) _PyEval_FiniThreads(void); +PyAPI_FUNC(void) _PyEval_FiniThreads2(void); + #ifdef __cplusplus } #endif diff --git a/Modules/main.c b/Modules/main.c index 68f0b99..f77bbd2 100644 --- a/Modules/main.c +++ b/Modules/main.c @@ -1,6 +1,7 @@ /* Python interpreter main program */ #include "Python.h" +#include "pycore_ceval.h" /* _PyEval_FiniThreads2() */ #include "pycore_coreconfig.h" #include "pycore_pylifecycle.h" #include "pycore_pymem.h" @@ -525,15 +526,15 @@ done: /* --- pymain_main() ---------------------------------------------- */ +/* Free global variables which cannot be freed in Py_Finalize(): + configuration options set before Py_Initialize() which should + remain valid after Py_Finalize(), since + Py_Initialize()-Py_Finalize() can be called multiple times. */ static void pymain_free(void) { _PyImport_Fini2(); - - /* Free global variables which cannot be freed in Py_Finalize(): - configuration options set before Py_Initialize() which should - remain valid after Py_Finalize(), since - Py_Initialize()-Py_Finalize() can be called multiple times. */ + _PyEval_FiniThreads2(); _PyPathConfig_ClearGlobal(); _Py_ClearStandardStreamEncoding(); _Py_ClearArgcArgv(); diff --git a/Python/ceval.c b/Python/ceval.c index ccd0427..5480fba 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -188,20 +188,26 @@ PyEval_InitThreads(void) } } + void _PyEval_FiniThreads(void) { + if (_PyRuntime.ceval.pending.lock != NULL) { + PyThread_free_lock(_PyRuntime.ceval.pending.lock); + _PyRuntime.ceval.pending.lock = NULL; + } +} + + +void +_PyEval_FiniThreads2(void) +{ if (!gil_created()) { return; } destroy_gil(); assert(!gil_created()); - - if (_PyRuntime.ceval.pending.lock != NULL) { - PyThread_free_lock(_PyRuntime.ceval.pending.lock); - _PyRuntime.ceval.pending.lock = NULL; - } } static inline void diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c index d93fe06..0836e18 100644 --- a/Python/pylifecycle.c +++ b/Python/pylifecycle.c @@ -4,8 +4,9 @@ #include "Python-ast.h" #undef Yield /* undefine macro conflicting with */ -#include "pycore_coreconfig.h" +#include "pycore_ceval.h" /* _PyEval_FiniThreads() */ #include "pycore_context.h" +#include "pycore_coreconfig.h" #include "pycore_fileutils.h" #include "pycore_hamt.h" #include "pycore_pathconfig.h" @@ -555,12 +556,11 @@ pycore_create_interpreter(_PyRuntimeState *runtime, return _Py_INIT_ERR("can't make first thread"); (void) PyThreadState_Swap(tstate); - /* We can't call _PyEval_FiniThreads() in Py_FinalizeEx because - destroying the GIL might fail when it is being referenced from - another running thread (see issue #9901). + /* Destroying the GIL in Py_FinalizeEx might fail when it is being + referenced from another running thread (see bpo-9901). Instead we destroy the previously created GIL here, which ensures that we can call Py_Initialize / Py_FinalizeEx multiple times. */ - _PyEval_FiniThreads(); + _PyEval_FiniThreads2(); /* Auto-thread-state API */ _PyGILState_Init(runtime, interp, tstate); @@ -1357,6 +1357,7 @@ Py_FinalizeEx(void) call_ll_exitfuncs(runtime); + _PyEval_FiniThreads(); _PyRuntime_Finalize(); return status; } -- cgit v0.12