gh-105603: Change the PyInterpreterConfig.own gil Field (gh-105620)

We are changing it to be more flexible that a strict bool can be for possible future expanded used cases.

Author: ericsnowcurrently

Include/cpython/initconfig.h

@@ -244,6 +244,10 @@ PyAPI_FUNC(PyStatus) PyConfig_SetWideStringList(PyConfig *config,
 
 /* --- PyInterpreterConfig ------------------------------------ */
 
+#define PyInterpreterConfig_DEFAULT_GIL (0)
+#define PyInterpreterConfig_SHARED_GIL (1)
+#define PyInterpreterConfig_OWN_GIL (2)
+
 typedef struct {
     // XXX "allow_object_sharing"?  "own_objects"?
     int use_main_obmalloc;
@@ -252,7 +256,7 @@ typedef struct {
     int allow_threads;
     int allow_daemon_threads;
     int check_multi_interp_extensions;
-    int own_gil;
+    int gil;
 } PyInterpreterConfig;
 
 #define _PyInterpreterConfig_INIT \
@@ -263,7 +267,7 @@ typedef struct {
         .allow_threads = 1, \
         .allow_daemon_threads = 0, \
         .check_multi_interp_extensions = 1, \
-        .own_gil = 1, \
+        .gil = PyInterpreterConfig_OWN_GIL, \
     }
 
 #define _PyInterpreterConfig_LEGACY_INIT \
@@ -274,7 +278,7 @@ typedef struct {
         .allow_threads = 1, \
         .allow_daemon_threads = 1, \
         .check_multi_interp_extensions = 0, \
-        .own_gil = 0, \
+        .gil = PyInterpreterConfig_SHARED_GIL, \
     }
 
 /* --- Helper functions --------------------------------------- */

Lib/test/support/__init__.py

@@ -1813,13 +1813,16 @@ def run_in_subinterp(code):
     return _testcapi.run_in_subinterp(code)
 
 
-def run_in_subinterp_with_config(code, **config):
+def run_in_subinterp_with_config(code, *, own_gil=None, **config):
     """
     Run code in a subinterpreter. Raise unittest.SkipTest if the tracemalloc
     module is enabled.
     """
     _check_tracemalloc()
     import _testcapi
+    if own_gil is not None:
+        assert 'gil' not in config, (own_gil, config)
+        config['gil'] = 2 if own_gil else 1
     return _testcapi.run_in_subinterp_with_config(code, **config)
 
 

Lib/test/test_import/__init__.py

@@ -1640,9 +1640,10 @@ class SubinterpImportTests(unittest.TestCase):
     )
     ISOLATED = dict(
         use_main_obmalloc=False,
-        own_gil=True,
+        gil=2,
     )
     NOT_ISOLATED = {k: not v for k, v in ISOLATED.items()}
+    NOT_ISOLATED['gil'] = 1
 
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
     def pipe(self):

Misc/NEWS.d/next/C API/2023-06-09-19-16-57.gh-issue-105603.-z6G22.rst

@@ -0,0 +1,5 @@
+We've renamed the new (in 3.12) ``PyInterpreterConfig.own_gil`` to
+``PyInterpreterConfig.gil`` and changed the meaning of the value from "bool"
+to an integer with supported values of ``PyInterpreterConfig_DEFAULT_GIL``,
+``PyInterpreterConfig_SHARED_GIL``, and ``PyInterpreterConfig_OWN_GIL``. The
+default is "shared".

Modules/_testcapimodule.c

@@ -1426,7 +1426,7 @@ run_in_subinterp_with_config(PyObject *self, PyObject *args, PyObject *kwargs)
     int allow_threads = -1;
     int allow_daemon_threads = -1;
     int check_multi_interp_extensions = -1;
-    int own_gil = -1;
+    int gil = -1;
     int r;
     PyThreadState *substate, *mainstate;
     /* only initialise 'cflags.cf_flags' to test backwards compatibility */
@@ -1439,15 +1439,15 @@ run_in_subinterp_with_config(PyObject *self, PyObject *args, PyObject *kwargs)
                              "allow_threads",
                              "allow_daemon_threads",
                              "check_multi_interp_extensions",
-                             "own_gil",
+                             "gil",
                              NULL};
     if (!PyArg_ParseTupleAndKeywords(args, kwargs,
-                    "s$ppppppp:run_in_subinterp_with_config", kwlist,
+                    "s$ppppppi:run_in_subinterp_with_config", kwlist,
                     &code, &use_main_obmalloc,
                     &allow_fork, &allow_exec,
                     &allow_threads, &allow_daemon_threads,
                     &check_multi_interp_extensions,
-                    &own_gil)) {
+                    &gil)) {
         return NULL;
     }
     if (use_main_obmalloc < 0) {
@@ -1466,8 +1466,8 @@ run_in_subinterp_with_config(PyObject *self, PyObject *args, PyObject *kwargs)
         PyErr_SetString(PyExc_ValueError, "missing allow_threads");
         return NULL;
     }
-    if (own_gil < 0) {
-        PyErr_SetString(PyExc_ValueError, "missing own_gil");
+    if (gil < 0) {
+        PyErr_SetString(PyExc_ValueError, "missing gil");
         return NULL;
     }
     if (allow_daemon_threads < 0) {
@@ -1490,7 +1490,7 @@ run_in_subinterp_with_config(PyObject *self, PyObject *args, PyObject *kwargs)
         .allow_threads = allow_threads,
         .allow_daemon_threads = allow_daemon_threads,
         .check_multi_interp_extensions = check_multi_interp_extensions,
-        .own_gil = own_gil,
+        .gil = gil,
     };
     PyStatus status = Py_NewInterpreterFromConfig(&substate, &config);
     if (PyStatus_Exception(status)) {

Python/pylifecycle.c

@@ -578,12 +578,14 @@ init_interp_settings(PyInterpreterState *interp,
         interp->feature_flags |= Py_RTFLAGS_MULTI_INTERP_EXTENSIONS;
     }
 
+    /* We check "gil" in init_interp_create_gil(). */
+
     return _PyStatus_OK();
 }
 
 
 static PyStatus
-init_interp_create_gil(PyThreadState *tstate, int own_gil)
+init_interp_create_gil(PyThreadState *tstate, int gil)
 {
     PyStatus status;
 
@@ -598,6 +600,15 @@ init_interp_create_gil(PyThreadState *tstate, int own_gil)
         return status;
     }
 
+    int own_gil;
+    switch (gil) {
+    case PyInterpreterConfig_DEFAULT_GIL: own_gil = 0; break;
+    case PyInterpreterConfig_SHARED_GIL: own_gil = 0; break;
+    case PyInterpreterConfig_OWN_GIL: own_gil = 1; break;
+    default:
+        return _PyStatus_ERR("invalid interpreter config 'gil' value");
+    }
+
     /* Create the GIL and take it */
     status = _PyEval_InitGIL(tstate, own_gil);
     if (_PyStatus_EXCEPTION(status)) {
@@ -633,7 +644,7 @@ pycore_create_interpreter(_PyRuntimeState *runtime,
 
     PyInterpreterConfig config = _PyInterpreterConfig_LEGACY_INIT;
     // The main interpreter always has its own GIL.
-    config.own_gil = 1;
+    config.gil = PyInterpreterConfig_OWN_GIL;
     status = init_interp_settings(interp, &config);
     if (_PyStatus_EXCEPTION(status)) {
         return status;
@@ -647,7 +658,7 @@ pycore_create_interpreter(_PyRuntimeState *runtime,
     // XXX For now we do this before the GIL is created.
     (void) _PyThreadState_SwapNoGIL(tstate);
 
-    status = init_interp_create_gil(tstate, config.own_gil);
+    status = init_interp_create_gil(tstate, config.gil);
     if (_PyStatus_EXCEPTION(status)) {
         return status;
     }
@@ -2057,7 +2068,7 @@ new_interpreter(PyThreadState **tstate_p, const PyInterpreterConfig *config)
         goto error;
     }
 
-    status = init_interp_create_gil(tstate, config->own_gil);
+    status = init_interp_create_gil(tstate, config->gil);
     if (_PyStatus_EXCEPTION(status)) {
         goto error;
     }