diff options
Diffstat (limited to 'Python/pystate.c')
| -rw-r--r-- | Python/pystate.c | 37 |
1 files changed, 21 insertions, 16 deletions
diff --git a/Python/pystate.c b/Python/pystate.c index eb2dfa6e3a..7154aeac24 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -47,7 +47,9 @@ static int autoTLSkey = 0; static PyInterpreterState *interp_head = NULL; -PyThreadState *_PyThreadState_Current = NULL; +/* Assuming the current thread holds the GIL, this is the + PyThreadState for the current thread. */ +_Py_atomic_address _PyThreadState_Current = {NULL}; PyThreadFrameGetter _PyThreadState_GetFrame = NULL; #ifdef WITH_THREAD @@ -334,7 +336,7 @@ tstate_delete_common(PyThreadState *tstate) void PyThreadState_Delete(PyThreadState *tstate) { - if (tstate == _PyThreadState_Current) + if (tstate == _Py_atomic_load_relaxed(&_PyThreadState_Current)) Py_FatalError("PyThreadState_Delete: tstate is still current"); tstate_delete_common(tstate); #ifdef WITH_THREAD @@ -348,11 +350,12 @@ PyThreadState_Delete(PyThreadState *tstate) void PyThreadState_DeleteCurrent() { - PyThreadState *tstate = _PyThreadState_Current; + PyThreadState *tstate = (PyThreadState*)_Py_atomic_load_relaxed( + &_PyThreadState_Current); if (tstate == NULL) Py_FatalError( "PyThreadState_DeleteCurrent: no current tstate"); - _PyThreadState_Current = NULL; + _Py_atomic_store_relaxed(&_PyThreadState_Current, NULL); tstate_delete_common(tstate); if (autoTLSkey && PyThread_get_key_value(autoTLSkey) == tstate) PyThread_delete_key_value(autoTLSkey); @@ -364,19 +367,22 @@ PyThreadState_DeleteCurrent() PyThreadState * PyThreadState_Get(void) { - if (_PyThreadState_Current == NULL) + PyThreadState *tstate = (PyThreadState*)_Py_atomic_load_relaxed( + &_PyThreadState_Current); + if (tstate == NULL) Py_FatalError("PyThreadState_Get: no current thread"); - return _PyThreadState_Current; + return tstate; } PyThreadState * PyThreadState_Swap(PyThreadState *newts) { - PyThreadState *oldts = _PyThreadState_Current; + PyThreadState *oldts = (PyThreadState*)_Py_atomic_load_relaxed( + &_PyThreadState_Current); - _PyThreadState_Current = newts; + _Py_atomic_store_relaxed(&_PyThreadState_Current, newts); /* It should not be possible for more than one thread state to be used for a thread. Check this the best we can in debug builds. @@ -405,16 +411,18 @@ PyThreadState_Swap(PyThreadState *newts) PyObject * PyThreadState_GetDict(void) { - if (_PyThreadState_Current == NULL) + PyThreadState *tstate = (PyThreadState*)_Py_atomic_load_relaxed( + &_PyThreadState_Current); + if (tstate == NULL) return NULL; - if (_PyThreadState_Current->dict == NULL) { + if (tstate->dict == NULL) { PyObject *d; - _PyThreadState_Current->dict = d = PyDict_New(); + tstate->dict = d = PyDict_New(); if (d == NULL) PyErr_Clear(); } - return _PyThreadState_Current->dict; + return tstate->dict; } @@ -550,10 +558,7 @@ PyThreadState_IsCurrent(PyThreadState *tstate) { /* Must be the tstate for this thread */ assert(PyGILState_GetThisThreadState()==tstate); - /* On Windows at least, simple reads and writes to 32 bit values - are atomic. - */ - return tstate == _PyThreadState_Current; + return tstate == _Py_atomic_load_relaxed(&_PyThreadState_Current); } /* Internal initialization/finalization functions called by |