bpo-34301: Add _PyInterpreterState_Get() helper function (GH-8592)

sys_setcheckinterval() now uses a local variable to parse arguments,
before writing into interp->check_interval.

Include/pystate.h

@@ -245,6 +245,13 @@ typedef struct _ts {
 PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_New(void);
 PyAPI_FUNC(void) PyInterpreterState_Clear(PyInterpreterState *);
 PyAPI_FUNC(void) PyInterpreterState_Delete(PyInterpreterState *);
+#if !defined(Py_LIMITED_API)
+PyAPI_FUNC(PyInterpreterState *) _PyInterpreterState_Get(void);
+#endif
+#ifdef Py_BUILD_CORE
+   /* Macro which should only be used for performance critical code */
+#  define _PyInterpreterState_GET_UNSAFE() (PyThreadState_GET()->interp)
+#endif
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03070000
 /* New in 3.7 */
 PyAPI_FUNC(int64_t) PyInterpreterState_GetID(PyInterpreterState *);

Modules/_threadmodule.c

@@ -1049,7 +1049,7 @@ thread_PyThread_start_new_thread(PyObject *self, PyObject *fargs)
     boot = PyMem_NEW(struct bootstate, 1);
     if (boot == NULL)
         return PyErr_NoMemory();
-    boot->interp = PyThreadState_GET()->interp;
+    boot->interp = _PyInterpreterState_Get();
     boot->func = func;
     boot->args = args;
     boot->keyw = keyw;
@@ -1154,8 +1154,8 @@ A thread's identity may be reused for another thread after it exits.");
 static PyObject *
 thread__count(PyObject *self, PyObject *Py_UNUSED(ignored))
 {
-    PyThreadState *tstate = PyThreadState_Get();
+    PyInterpreterState *interp = _PyInterpreterState_Get();
-    return PyLong_FromLong(tstate->interp->num_threads);
+    return PyLong_FromLong(interp->num_threads);
 }
 
 PyDoc_STRVAR(_count_doc,
@@ -1348,7 +1348,7 @@ PyInit__thread(void)
     PyObject *m, *d, *v;
     double time_max;
     double timeout_max;
-    PyThreadState *tstate = PyThreadState_Get();
+    PyInterpreterState *interp = _PyInterpreterState_Get();
 
     /* Initialize types: */
     if (PyType_Ready(&localdummytype) < 0)
@@ -1395,7 +1395,7 @@ PyInit__thread(void)
     if (PyModule_AddObject(m, "_local", (PyObject *)&localtype) < 0)
         return NULL;
 
-    tstate->interp->num_threads = 0;
+    interp->num_threads = 0;
 
     str_dict = PyUnicode_InternFromString("__dict__");
     if (str_dict == NULL)

Modules/_xxsubinterpretersmodule.c

@@ -26,10 +26,9 @@ _copy_raw_string(PyObject *strobj)
 static PyInterpreterState *
 _get_current(void)
 {
-    PyThreadState *tstate = PyThreadState_Get();
+    // _PyInterpreterState_Get() aborts if lookup fails, so don't need
-    // PyThreadState_Get() aborts if lookup fails, so we don't need
     // to check the result for NULL.
-    return tstate->interp;
+    return _PyInterpreterState_Get();
 }
 
 static int64_t
@@ -1941,7 +1940,7 @@ _run_script_in_interpreter(PyInterpreterState *interp, const char *codestr,
 
     // Switch to interpreter.
     PyThreadState *save_tstate = NULL;
-    if (interp != PyThreadState_Get()->interp) {
+    if (interp != _PyInterpreterState_Get()) {
         // XXX Using the "head" thread isn't strictly correct.
         PyThreadState *tstate = PyInterpreterState_ThreadHead(interp);
         // XXX Possible GILState issues?

Modules/posixmodule.c

@@ -437,7 +437,7 @@ run_at_forkers(PyObject *lst, int reverse)
 void
 PyOS_BeforeFork(void)
 {
-    run_at_forkers(PyThreadState_Get()->interp->before_forkers, 1);
+    run_at_forkers(_PyInterpreterState_Get()->before_forkers, 1);
 
     _PyImport_AcquireLock();
 }
@@ -448,7 +448,7 @@ PyOS_AfterFork_Parent(void)
     if (_PyImport_ReleaseLock() <= 0)
         Py_FatalError("failed releasing import lock after fork");
 
-    run_at_forkers(PyThreadState_Get()->interp->after_forkers_parent, 0);
+    run_at_forkers(_PyInterpreterState_Get()->after_forkers_parent, 0);
 }
 
 void
@@ -459,7 +459,7 @@ PyOS_AfterFork_Child(void)
     _PyImport_ReInitLock();
     _PySignal_AfterFork();
 
-    run_at_forkers(PyThreadState_Get()->interp->after_forkers_child, 0);
+    run_at_forkers(_PyInterpreterState_Get()->after_forkers_child, 0);
 }
 
 static int
@@ -5655,7 +5655,7 @@ os_register_at_fork_impl(PyObject *module, PyObject *before,
         check_null_or_callable(after_in_parent, "after_in_parent")) {
         return NULL;
     }
-    interp = PyThreadState_Get()->interp;
+    interp = _PyInterpreterState_Get();
 
     if (register_at_forker(&interp->before_forkers, before)) {
         return NULL;

Modules/zipimport.c

@@ -1074,7 +1074,7 @@ read_directory(PyObject *archive)
         if (flags & 0x0800) {
             charset = "utf-8";
         }
-        else if (!PyThreadState_GET()->interp->codecs_initialized) {
+        else if (!_PyInterpreterState_Get()->codecs_initialized) {
             /* During bootstrap, we may need to load the encodings
                package from a ZIP file. But the cp437 encoding is implemented
                in Python in the encodings package.
@@ -1351,7 +1351,7 @@ unmarshal_code(PyObject *pathname, PyObject *data, time_t mtime)
 
     uint32_t flags = get_uint32(buf + 4);
     if (flags != 0) {
-        _PyCoreConfig *config = &PyThreadState_GET()->interp->core_config;
+        _PyCoreConfig *config = &_PyInterpreterState_Get()->core_config;
         // Hash-based pyc. We currently refuse to handle checked hash-based
         // pycs. We could validate hash-based pycs against the source, but it
         // seems likely that most people putting hash-based pycs in a zipfile

Objects/codeobject.c

@@ -3,6 +3,7 @@
 #include "Python.h"
 #include "code.h"
 #include "structmember.h"
+#include "internal/pystate.h"
 
 /* Holder for co_extra information */
 typedef struct {
@@ -428,7 +429,7 @@ static void
 code_dealloc(PyCodeObject *co)
 {
     if (co->co_extra != NULL) {
-        PyInterpreterState *interp = PyThreadState_Get()->interp;
+        PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
         _PyCodeObjectExtra *co_extra = co->co_extra;
 
         for (Py_ssize_t i = 0; i < co_extra->ce_size; i++) {
@@ -871,7 +872,7 @@ _PyCode_GetExtra(PyObject *code, Py_ssize_t index, void **extra)
 int
 _PyCode_SetExtra(PyObject *code, Py_ssize_t index, void *extra)
 {
-    PyInterpreterState *interp = PyThreadState_Get()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
 
     if (!PyCode_Check(code) || index < 0 ||
             index >= interp->co_extra_user_count) {

Objects/listobject.c

@@ -85,7 +85,7 @@ static size_t count_reuse = 0;
 static void
 show_alloc(void)
 {
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     if (!interp->core_config.show_alloc_count) {
         return;
     }

Objects/moduleobject.c

@@ -173,7 +173,7 @@ _add_methods_to_object(PyObject *module, PyObject *name, PyMethodDef *functions)
 PyObject *
 PyModule_Create2(struct PyModuleDef* module, int module_api_version)
 {
-    if (!_PyImport_IsInitialized(PyThreadState_GET()->interp))
+    if (!_PyImport_IsInitialized(_PyInterpreterState_Get()))
         Py_FatalError("Python import machinery not initialized");
     return _PyModule_CreateInitialized(module, module_api_version);
 }
@@ -693,8 +693,7 @@ module_dealloc(PyModuleObject *m)
 static PyObject *
 module_repr(PyModuleObject *m)
 {
-    PyThreadState *tstate = PyThreadState_GET();
+    PyInterpreterState *interp = _PyInterpreterState_Get();
-    PyInterpreterState *interp = tstate->interp;
 
     return PyObject_CallMethod(interp->importlib, "_module_repr", "O", m);
 }

Objects/object.c

@@ -96,7 +96,7 @@ extern Py_ssize_t null_strings, one_strings;
 void
 dump_counts(FILE* f)
 {
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     if (!interp->core_config.show_alloc_count) {
         return;
     }

Objects/tupleobject.c

@@ -44,7 +44,7 @@ static Py_ssize_t count_tracked = 0;
 static void
 show_track(void)
 {
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     if (!interp->core_config.show_alloc_count) {
         return;
     }

Objects/unicodeobject.c

@@ -3413,7 +3413,7 @@ PyUnicode_EncodeFSDefault(PyObject *unicode)
 #if defined(__APPLE__)
     return _PyUnicode_AsUTF8String(unicode, Py_FileSystemDefaultEncodeErrors);
 #else
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     /* Bootstrap check: if the filesystem codec is implemented in Python, we
        cannot use it to encode and decode filenames before it is loaded. Load
        the Python codec requires to encode at least its own filename. Use the C
@@ -3639,7 +3639,7 @@ PyUnicode_DecodeFSDefaultAndSize(const char *s, Py_ssize_t size)
 #if defined(__APPLE__)
     return PyUnicode_DecodeUTF8Stateful(s, size, Py_FileSystemDefaultEncodeErrors, NULL);
 #else
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     /* Bootstrap check: if the filesystem codec is implemented in Python, we
        cannot use it to encode and decode filenames before it is loaded. Load
        the Python codec requires to encode at least its own filename. Use the C

Programs/_testembed.c

@@ -306,7 +306,7 @@ dump_config(void)
         exit(1); \
     }
 
-    PyInterpreterState *interp = PyThreadState_Get()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     _PyCoreConfig *config = &interp->core_config;
 
     printf("install_signal_handlers = %i\n", config->install_signal_handlers);

Python/_warnings.c

@@ -78,7 +78,7 @@ get_warnings_attr(_Py_Identifier *attr_id, int try_import)
            gone, then we can't even use PyImport_GetModule without triggering
            an interpreter abort.
         */
-        if (!PyThreadState_GET()->interp->modules) {
+        if (!_PyInterpreterState_GET_UNSAFE()->modules) {
             return NULL;
         }
         warnings_module = PyImport_GetModule(warnings_str);
@@ -686,7 +686,7 @@ setup_context(Py_ssize_t stack_level, PyObject **filename, int *lineno,
     }
 
     if (f == NULL) {
-        globals = PyThreadState_Get()->interp->sysdict;
+        globals = _PyInterpreterState_GET_UNSAFE()->sysdict;
         *filename = PyUnicode_FromString("sys");
         *lineno = 1;
     }

Python/ceval.c

@@ -532,8 +532,8 @@ PyEval_EvalFrame(PyFrameObject *f) {
 PyObject *
 PyEval_EvalFrameEx(PyFrameObject *f, int throwflag)
 {
-    PyThreadState *tstate = PyThreadState_GET();
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
-    return tstate->interp->eval_frame(f, throwflag);
+    return interp->eval_frame(f, throwflag);
 }
 
 PyObject* _Py_HOT_FUNCTION
@@ -4435,7 +4435,7 @@ PyEval_GetBuiltins(void)
 {
     PyFrameObject *current_frame = PyEval_GetFrame();
     if (current_frame == NULL)
-        return PyThreadState_GET()->interp->builtins;
+        return _PyInterpreterState_GET_UNSAFE()->builtins;
     else
         return current_frame->f_builtins;
 }
@@ -4769,7 +4769,7 @@ import_name(PyFrameObject *f, PyObject *name, PyObject *fromlist, PyObject *leve
     }
 
     /* Fast path for not overloaded __import__. */
-    if (import_func == PyThreadState_GET()->interp->import_func) {
+    if (import_func == _PyInterpreterState_GET_UNSAFE()->import_func) {
         int ilevel = _PyLong_AsInt(level);
         if (ilevel == -1 && PyErr_Occurred()) {
             return NULL;
@@ -5136,7 +5136,7 @@ _Py_GetDXProfile(PyObject *self, PyObject *args)
 Py_ssize_t
 _PyEval_RequestCodeExtraIndex(freefunc free)
 {
-    PyInterpreterState *interp = PyThreadState_Get()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     Py_ssize_t new_index;
 
     if (interp->co_extra_user_count == MAX_CO_EXTRA_USERS - 1) {

Python/codecs.c

@@ -32,7 +32,7 @@ static int _PyCodecRegistry_Init(void); /* Forward */
 
 int PyCodec_Register(PyObject *search_function)
 {
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
         goto onError;
     if (search_function == NULL) {
@@ -99,7 +99,6 @@ PyObject *normalizestring(const char *string)
 
 PyObject *_PyCodec_Lookup(const char *encoding)
 {
-    PyInterpreterState *interp;
     PyObject *result, *args = NULL, *v;
     Py_ssize_t i, len;
 
@@ -108,7 +107,7 @@ PyObject *_PyCodec_Lookup(const char *encoding)
         goto onError;
     }
 
-    interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
         goto onError;
 
@@ -187,11 +186,10 @@ PyObject *_PyCodec_Lookup(const char *encoding)
 
 int _PyCodec_Forget(const char *encoding)
 {
-    PyInterpreterState *interp;
     PyObject *v;
     int result;
 
-    interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     if (interp->codec_search_path == NULL) {
         return -1;
     }
@@ -624,7 +622,7 @@ PyObject *_PyCodec_DecodeText(PyObject *object,
    Return 0 on success, -1 on error */
 int PyCodec_RegisterError(const char *name, PyObject *error)
 {
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
         return -1;
     if (!PyCallable_Check(error)) {
@@ -642,7 +640,7 @@ PyObject *PyCodec_LookupError(const char *name)
 {
     PyObject *handler = NULL;
 
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
         return NULL;
 
@@ -1494,7 +1492,7 @@ static int _PyCodecRegistry_Init(void)
         }
     };
 
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     PyObject *mod;
     unsigned i;
 

Python/dynload_shlib.c

@@ -91,7 +91,7 @@ _PyImport_FindSharedFuncptr(const char *prefix,
         }
     }
 
-    dlopenflags = PyThreadState_GET()->interp->dlopenflags;
+    dlopenflags = _PyInterpreterState_Get()->dlopenflags;
 
     handle = dlopen(pathname, dlopenflags);
 

Python/import.c

@@ -304,7 +304,7 @@ _PyImport_Fini2(void)
 PyObject *
 PyImport_GetModuleDict(void)
 {
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     if (interp->modules == NULL) {
         Py_FatalError("PyImport_GetModuleDict: no module dictionary!");
     }
@@ -397,7 +397,7 @@ PyImport_Cleanup(void)
 {
     Py_ssize_t pos;
     PyObject *key, *value, *dict;
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     PyObject *modules = PyImport_GetModuleDict();
     PyObject *weaklist = NULL;
     const char * const *p;
@@ -592,7 +592,7 @@ long
 PyImport_GetMagicNumber(void)
 {
     long res;
-    PyInterpreterState *interp = PyThreadState_Get()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     PyObject *external, *pyc_magic;
 
     external = PyObject_GetAttrString(interp->importlib, "_bootstrap_external");
@@ -892,7 +892,7 @@ PyImport_ExecCodeModuleWithPathnames(const char *name, PyObject *co,
             goto error;
     }
     else if (cpathobj != NULL) {
-        PyInterpreterState *interp = PyThreadState_GET()->interp;
+        PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
         _Py_IDENTIFIER(_get_sourcefile);
 
         if (interp == NULL) {
@@ -972,7 +972,7 @@ PyImport_ExecCodeModuleObject(PyObject *name, PyObject *co, PyObject *pathname,
                               PyObject *cpathname)
 {
     PyObject *d, *external, *res;
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     _Py_IDENTIFIER(_fix_up_module);
 
     d = module_dict_for_exec(name);
@@ -1619,7 +1619,7 @@ import_find_and_load(PyObject *abs_name)
 {
     _Py_IDENTIFIER(_find_and_load);
     PyObject *mod = NULL;
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     int import_time = interp->core_config.import_time;
     static int import_level;
     static _PyTime_t accumulated;
@@ -1680,7 +1680,7 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *globals,
     PyObject *final_mod = NULL;
     PyObject *mod = NULL;
     PyObject *package = NULL;
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_GET_UNSAFE();
     int has_from;
 
     if (name == NULL) {
@@ -2289,7 +2289,7 @@ PyInit__imp(void)
     d = PyModule_GetDict(m);
     if (d == NULL)
         goto failure;
-    _PyCoreConfig *config = &PyThreadState_GET()->interp->core_config;
+    _PyCoreConfig *config = &_PyInterpreterState_Get()->core_config;
     PyObject *pyc_mode = PyUnicode_FromString(config->_check_hash_pycs_mode);
     if (pyc_mode == NULL) {
         goto failure;

Python/pylifecycle.c

@@ -2123,11 +2123,7 @@ _Py_FatalInitError(_PyInitError err)
 /* For the atexit module. */
 void _Py_PyAtExit(void (*func)(PyObject *), PyObject *module)
 {
-    PyThreadState *ts;
+    PyInterpreterState *is = _PyInterpreterState_Get();
-    PyInterpreterState *is;
-
-    ts = PyThreadState_GET();
-    is = ts->interp;
 
     /* Guard against API misuse (see bpo-17852) */
     assert(is->pyexitfunc == NULL || is->pyexitfunc == func);

Python/pystate.c

@@ -264,6 +264,21 @@ PyInterpreterState_Delete(PyInterpreterState *interp)
 }
 
 
+PyInterpreterState *
+_PyInterpreterState_Get(void)
+{
+    PyThreadState *tstate = GET_TSTATE();
+    if (tstate == NULL) {
+        Py_FatalError("_PyInterpreterState_Get(): no current thread state");
+    }
+    PyInterpreterState *interp = tstate->interp;
+    if (interp == NULL) {
+        Py_FatalError("_PyInterpreterState_Get(): no current interpreter");
+    }
+    return interp;
+}
+
+
 int64_t
 PyInterpreterState_GetID(PyInterpreterState *interp)
 {
@@ -1184,10 +1199,9 @@ _check_xidata(_PyCrossInterpreterData *data)
 int
 _PyObject_GetCrossInterpreterData(PyObject *obj, _PyCrossInterpreterData *data)
 {
-    PyThreadState *tstate = PyThreadState_Get();
+    // _PyInterpreterState_Get() aborts if lookup fails, so we don't need
-    // PyThreadState_Get() aborts if lookup fails, so we don't need
     // to check the result for NULL.
-    PyInterpreterState *interp = tstate->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
 
     // Reset data before re-populating.
     *data = (_PyCrossInterpreterData){0};
@@ -1235,7 +1249,7 @@ _call_in_interpreter(PyInterpreterState *interp,
      * naive approach.
      */
     PyThreadState *save_tstate = NULL;
-    if (interp != PyThreadState_Get()->interp) {
+    if (interp != _PyInterpreterState_Get()) {
         // XXX Using the "head" thread isn't strictly correct.
         PyThreadState *tstate = PyInterpreterState_ThreadHead(interp);
         // XXX Possible GILState issues?

Python/pythonrun.c

@@ -92,7 +92,7 @@ PyRun_InteractiveLoopFlags(FILE *fp, const char *filename_str, PyCompilerFlags *
     PyCompilerFlags local_flags;
     int nomem_count = 0;
 #ifdef Py_REF_DEBUG
-    int show_ref_count = PyThreadState_GET()->interp->core_config.show_ref_count;
+    int show_ref_count = _PyInterpreterState_Get()->core_config.show_ref_count;
 #endif
 
     filename = PyUnicode_DecodeFSDefault(filename_str);
@@ -336,17 +336,13 @@ maybe_pyc_file(FILE *fp, const char* filename, const char* ext, int closeit)
 static int
 set_main_loader(PyObject *d, const char *filename, const char *loader_name)
 {
-    PyInterpreterState *interp;
-    PyThreadState *tstate;
     PyObject *filename_obj, *bootstrap, *loader_type = NULL, *loader;
     int result = 0;
 
     filename_obj = PyUnicode_DecodeFSDefault(filename);
     if (filename_obj == NULL)
         return -1;
-    /* Get current thread state and interpreter pointer */
+    PyInterpreterState *interp = _PyInterpreterState_Get();
-    tstate = PyThreadState_GET();
-    interp = tstate->interp;
     bootstrap = PyObject_GetAttrString(interp->importlib,
                                        "_bootstrap_external");
     if (bootstrap != NULL) {

Python/sysmodule.c

@@ -56,52 +56,56 @@ _Py_IDENTIFIER(write);
 PyObject *
 _PySys_GetObjectId(_Py_Identifier *key)
 {
-    PyThreadState *tstate = PyThreadState_GET();
+    PyObject *sd = _PyInterpreterState_GET_UNSAFE()->sysdict;
-    PyObject *sd = tstate->interp->sysdict;
+    if (sd == NULL) {
-    if (sd == NULL)
         return NULL;
+    }
     return _PyDict_GetItemId(sd, key);
 }
 
 PyObject *
 PySys_GetObject(const char *name)
 {
-    PyThreadState *tstate = PyThreadState_GET();
+    PyObject *sd = _PyInterpreterState_GET_UNSAFE()->sysdict;
-    PyObject *sd = tstate->interp->sysdict;
+    if (sd == NULL) {
-    if (sd == NULL)
         return NULL;
+    }
     return PyDict_GetItemString(sd, name);
 }
 
 int
 _PySys_SetObjectId(_Py_Identifier *key, PyObject *v)
 {
-    PyThreadState *tstate = PyThreadState_GET();
+    PyObject *sd = _PyInterpreterState_GET_UNSAFE()->sysdict;
-    PyObject *sd = tstate->interp->sysdict;
     if (v == NULL) {
-        if (_PyDict_GetItemId(sd, key) == NULL)
+        if (_PyDict_GetItemId(sd, key) == NULL) {
             return 0;
-        else
+        }
+        else {
             return _PyDict_DelItemId(sd, key);
         }
-    else
+    }
+    else {
         return _PyDict_SetItemId(sd, key, v);
     }
+}
 
 int
 PySys_SetObject(const char *name, PyObject *v)
 {
-    PyThreadState *tstate = PyThreadState_GET();
+    PyObject *sd = _PyInterpreterState_GET_UNSAFE()->sysdict;
-    PyObject *sd = tstate->interp->sysdict;
     if (v == NULL) {
-        if (PyDict_GetItemString(sd, name) == NULL)
+        if (PyDict_GetItemString(sd, name) == NULL) {
             return 0;
-        else
+        }
+        else {
             return PyDict_DelItemString(sd, name);
         }
-    else
+    }
+    else {
         return PyDict_SetItemString(sd, name, v);
     }
+}
 
 static PyObject *
 sys_breakpointhook(PyObject *self, PyObject *const *args, Py_ssize_t nargs, PyObject *keywords)
@@ -626,9 +630,13 @@ sys_setcheckinterval(PyObject *self, PyObject *args)
                      "are deprecated.  Use sys.setswitchinterval() "
                      "instead.", 1) < 0)
         return NULL;
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+
-    if (!PyArg_ParseTuple(args, "i:setcheckinterval", &interp->check_interval))
+    int check_interval;
+    if (!PyArg_ParseTuple(args, "i:setcheckinterval", &check_interval))
         return NULL;
+
+    PyInterpreterState *interp = _PyInterpreterState_Get();
+    interp->check_interval = check_interval;
     Py_RETURN_NONE;
 }
 
@@ -647,7 +655,7 @@ sys_getcheckinterval(PyObject *self, PyObject *args)
                      "are deprecated.  Use sys.getswitchinterval() "
                      "instead.", 1) < 0)
         return NULL;
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
+    PyInterpreterState *interp = _PyInterpreterState_Get();
     return PyLong_FromLong(interp->check_interval);
 }
 
@@ -1154,12 +1162,10 @@ static PyObject *
 sys_setdlopenflags(PyObject *self, PyObject *args)
 {
     int new_val;
-    PyThreadState *tstate = PyThreadState_GET();
     if (!PyArg_ParseTuple(args, "i:setdlopenflags", &new_val))
         return NULL;
-    if (!tstate)
+    PyInterpreterState *interp = _PyInterpreterState_Get();
-        return NULL;
+    interp->dlopenflags = new_val;
-    tstate->interp->dlopenflags = new_val;
     Py_RETURN_NONE;
 }
 
@@ -1176,10 +1182,8 @@ can be found in the os module (RTLD_xxx constants, e.g. os.RTLD_LAZY).");
 static PyObject *
 sys_getdlopenflags(PyObject *self, PyObject *args)
 {
-    PyThreadState *tstate = PyThreadState_GET();
+    PyInterpreterState *interp = _PyInterpreterState_Get();
-    if (!tstate)
+    return PyLong_FromLong(interp->dlopenflags);
-        return NULL;
-    return PyLong_FromLong(tstate->interp->dlopenflags);
 }
 
 PyDoc_STRVAR(getdlopenflags_doc,

Python/thread.c

@@ -92,7 +92,7 @@ PyThread_init_thread(void)
 size_t
 PyThread_get_stacksize(void)
 {
-    return PyThreadState_GET()->interp->pythread_stacksize;
+    return _PyInterpreterState_Get()->pythread_stacksize;
 }
 
 /* Only platforms defining a THREAD_SET_STACKSIZE() macro