diff options
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/pystate.c | 589 |
1 files changed, 352 insertions, 237 deletions
diff --git a/Python/pystate.c b/Python/pystate.c index 756c1c7..464e5d6 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -41,19 +41,36 @@ extern "C" { static void _PyThreadState_Delete(PyThreadState *tstate, int check_current); -/* the current thread state */ +/****************************************/ +/* helpers for the current thread state */ +/****************************************/ + +// API for the current thread state is further down. + +/* "current" means one of: + - bound to the current OS thread + - holds the GIL + */ + +//------------------------------------------------- +// a highly efficient lookup for the current thread +//------------------------------------------------- + +/* + The stored thread state is set by PyThraedState_Swap(). + + For each of these functions, the GIL mus be held by the current thread. + */ static inline PyThreadState * current_fast_get(_PyRuntimeState *runtime) { - // The GIL must be held by the current thread. return (PyThreadState*)_Py_atomic_load_relaxed(&runtime->tstate_current); } static inline void current_fast_set(_PyRuntimeState *runtime, PyThreadState *tstate) { - // The GIL must be held by the current thread. assert(tstate != NULL); _Py_atomic_store_relaxed(&runtime->tstate_current, (uintptr_t)tstate); } @@ -61,11 +78,20 @@ current_fast_set(_PyRuntimeState *runtime, PyThreadState *tstate) static inline void current_fast_clear(_PyRuntimeState *runtime) { - // The GIL must be held by the current thread. _Py_atomic_store_relaxed(&runtime->tstate_current, (uintptr_t)NULL); } +//------------------------------------------------ +// the thread state bound to the current OS thread +//------------------------------------------------ + +/* + The stored thread state is set by bind_tstate() (AKA PyThreadState_Bind(). + + The GIL does no need to be held for these. + */ + static int current_tss_initialized(_PyRuntimeState *runtime) { @@ -148,6 +174,7 @@ current_tss_reinit(_PyRuntimeState *runtime) } #endif + static void bind_tstate(PyThreadState *tstate) { @@ -213,6 +240,11 @@ unbind_tstate(PyThreadState *tstate) tstate->_status = PyThreadState_UNBOUND; } + +//---------------------------------------------- +// the thread state that currently holds the GIL +//---------------------------------------------- + /* This is not exported, as it is not reliable! It can only ever be compared to the state for the *current* thread. * If not equal, then it doesn't matter that the actual @@ -234,7 +266,13 @@ holds_gil(PyThreadState *tstate) } -/* the global runtime */ +/****************************/ +/* the global runtime state */ +/****************************/ + +//---------- +// lifecycle +//---------- /* Suppress deprecation warning for PyBytesObject.ob_shash */ _Py_COMP_DIAG_PUSH @@ -438,6 +476,16 @@ _PyRuntimeState_ReInitThreads(_PyRuntimeState *runtime) #endif +/*************************************/ +/* the per-interpreter runtime state */ +/*************************************/ + +//---------- +// lifecycle +//---------- + +/* Calling this indicates that the runtime is ready to create interpreters. */ + PyStatus _PyInterpreterState_Enable(_PyRuntimeState *runtime) { @@ -464,6 +512,7 @@ _PyInterpreterState_Enable(_PyRuntimeState *runtime) return _PyStatus_OK(); } + static PyInterpreterState * alloc_interpreter(void) { @@ -798,19 +847,40 @@ _PyInterpreterState_DeleteExceptMain(_PyRuntimeState *runtime) #endif -PyInterpreterState * -PyInterpreterState_Get(void) +// Used by finalize_modules() +void +_PyInterpreterState_ClearModules(PyInterpreterState *interp) { - PyThreadState *tstate = current_fast_get(&_PyRuntime); - _Py_EnsureTstateNotNULL(tstate); - PyInterpreterState *interp = tstate->interp; - if (interp == NULL) { - Py_FatalError("no current interpreter"); + if (!interp->modules_by_index) { + return; + } + + Py_ssize_t i; + for (i = 0; i < PyList_GET_SIZE(interp->modules_by_index); i++) { + PyObject *m = PyList_GET_ITEM(interp->modules_by_index, i); + if (PyModule_Check(m)) { + /* cleanup the saved copy of module dicts */ + PyModuleDef *md = PyModule_GetDef(m); + if (md) { + Py_CLEAR(md->m_base.m_copy); + } + } + } + + /* Setting modules_by_index to NULL could be dangerous, so we + clear the list instead. */ + if (PyList_SetSlice(interp->modules_by_index, + 0, PyList_GET_SIZE(interp->modules_by_index), + NULL)) { + PyErr_WriteUnraisable(interp->modules_by_index); } - return interp; } +//---------- +// accessors +//---------- + int64_t PyInterpreterState_GetID(PyInterpreterState *interp) { @@ -822,41 +892,6 @@ PyInterpreterState_GetID(PyInterpreterState *interp) } -static PyInterpreterState * -interp_look_up_id(_PyRuntimeState *runtime, int64_t requested_id) -{ - PyInterpreterState *interp = runtime->interpreters.head; - while (interp != NULL) { - int64_t id = PyInterpreterState_GetID(interp); - if (id < 0) { - return NULL; - } - if (requested_id == id) { - return interp; - } - interp = PyInterpreterState_Next(interp); - } - return NULL; -} - -PyInterpreterState * -_PyInterpreterState_LookUpID(int64_t requested_id) -{ - PyInterpreterState *interp = NULL; - if (requested_id >= 0) { - _PyRuntimeState *runtime = &_PyRuntime; - HEAD_LOCK(runtime); - interp = interp_look_up_id(runtime, requested_id); - HEAD_UNLOCK(runtime); - } - if (interp == NULL && !PyErr_Occurred()) { - PyErr_Format(PyExc_RuntimeError, - "unrecognized interpreter ID %lld", requested_id); - } - return interp; -} - - int _PyInterpreterState_IDInitref(PyInterpreterState *interp) { @@ -945,6 +980,76 @@ PyInterpreterState_GetDict(PyInterpreterState *interp) return interp->dict; } + +//----------------------------- +// look up an interpreter state +//----------------------------- + +/* Return the interpreter associated with the current OS thread. + + The GIL must be held. + */ + +PyInterpreterState * +PyInterpreterState_Get(void) +{ + PyThreadState *tstate = current_fast_get(&_PyRuntime); + _Py_EnsureTstateNotNULL(tstate); + PyInterpreterState *interp = tstate->interp; + if (interp == NULL) { + Py_FatalError("no current interpreter"); + } + return interp; +} + + +static PyInterpreterState * +interp_look_up_id(_PyRuntimeState *runtime, int64_t requested_id) +{ + PyInterpreterState *interp = runtime->interpreters.head; + while (interp != NULL) { + int64_t id = PyInterpreterState_GetID(interp); + if (id < 0) { + return NULL; + } + if (requested_id == id) { + return interp; + } + interp = PyInterpreterState_Next(interp); + } + return NULL; +} + +/* Return the interpreter state with the given ID. + + Fail with RuntimeError if the interpreter is not found. */ + +PyInterpreterState * +_PyInterpreterState_LookUpID(int64_t requested_id) +{ + PyInterpreterState *interp = NULL; + if (requested_id >= 0) { + _PyRuntimeState *runtime = &_PyRuntime; + HEAD_LOCK(runtime); + interp = interp_look_up_id(runtime, requested_id); + HEAD_UNLOCK(runtime); + } + if (interp == NULL && !PyErr_Occurred()) { + PyErr_Format(PyExc_RuntimeError, + "unrecognized interpreter ID %lld", requested_id); + } + return interp; +} + + +/********************************/ +/* the per-thread runtime state */ +/********************************/ + +//---------- +// lifecycle +//---------- + /* Minimum size of data stack chunk */ #define DATA_STACK_CHUNK_SIZE (16*1024) @@ -1107,140 +1212,6 @@ _PyThreadState_Init(PyThreadState *tstate) } void -_PyThreadState_Bind(PyThreadState *tstate) -{ - bind_tstate(tstate); -} - -PyObject* -PyState_FindModule(PyModuleDef* module) -{ - Py_ssize_t index = module->m_base.m_index; - PyInterpreterState *state = _PyInterpreterState_GET(); - PyObject *res; - if (module->m_slots) { - return NULL; - } - if (index == 0) - return NULL; - if (state->modules_by_index == NULL) - return NULL; - if (index >= PyList_GET_SIZE(state->modules_by_index)) - return NULL; - res = PyList_GET_ITEM(state->modules_by_index, index); - return res==Py_None ? NULL : res; -} - -int -_PyState_AddModule(PyThreadState *tstate, PyObject* module, PyModuleDef* def) -{ - if (!def) { - assert(_PyErr_Occurred(tstate)); - return -1; - } - if (def->m_slots) { - _PyErr_SetString(tstate, - PyExc_SystemError, - "PyState_AddModule called on module with slots"); - return -1; - } - - PyInterpreterState *interp = tstate->interp; - if (!interp->modules_by_index) { - interp->modules_by_index = PyList_New(0); - if (!interp->modules_by_index) { - return -1; - } - } - - while (PyList_GET_SIZE(interp->modules_by_index) <= def->m_base.m_index) { - if (PyList_Append(interp->modules_by_index, Py_None) < 0) { - return -1; - } - } - - return PyList_SetItem(interp->modules_by_index, - def->m_base.m_index, Py_NewRef(module)); -} - -int -PyState_AddModule(PyObject* module, PyModuleDef* def) -{ - if (!def) { - Py_FatalError("module definition is NULL"); - return -1; - } - - PyThreadState *tstate = current_fast_get(&_PyRuntime); - PyInterpreterState *interp = tstate->interp; - Py_ssize_t index = def->m_base.m_index; - if (interp->modules_by_index && - index < PyList_GET_SIZE(interp->modules_by_index) && - module == PyList_GET_ITEM(interp->modules_by_index, index)) - { - _Py_FatalErrorFormat(__func__, "module %p already added", module); - return -1; - } - return _PyState_AddModule(tstate, module, def); -} - -int -PyState_RemoveModule(PyModuleDef* def) -{ - PyThreadState *tstate = current_fast_get(&_PyRuntime); - PyInterpreterState *interp = tstate->interp; - - if (def->m_slots) { - _PyErr_SetString(tstate, - PyExc_SystemError, - "PyState_RemoveModule called on module with slots"); - return -1; - } - - Py_ssize_t index = def->m_base.m_index; - if (index == 0) { - Py_FatalError("invalid module index"); - } - if (interp->modules_by_index == NULL) { - Py_FatalError("Interpreters module-list not accessible."); - } - if (index > PyList_GET_SIZE(interp->modules_by_index)) { - Py_FatalError("Module index out of bounds."); - } - - return PyList_SetItem(interp->modules_by_index, index, Py_NewRef(Py_None)); -} - -// Used by finalize_modules() -void -_PyInterpreterState_ClearModules(PyInterpreterState *interp) -{ - if (!interp->modules_by_index) { - return; - } - - Py_ssize_t i; - for (i = 0; i < PyList_GET_SIZE(interp->modules_by_index); i++) { - PyObject *m = PyList_GET_ITEM(interp->modules_by_index, i); - if (PyModule_Check(m)) { - /* cleanup the saved copy of module dicts */ - PyModuleDef *md = PyModule_GetDef(m); - if (md) { - Py_CLEAR(md->m_base.m_copy); - } - } - } - - /* Setting modules_by_index to NULL could be dangerous, so we - clear the list instead. */ - if (PyList_SetSlice(interp->modules_by_index, - 0, PyList_GET_SIZE(interp->modules_by_index), - NULL)) { - PyErr_WriteUnraisable(interp->modules_by_index); - } -} - -void PyThreadState_Clear(PyThreadState *tstate) { int verbose = _PyInterpreterState_GetConfig(tstate->interp)->verbose; @@ -1406,59 +1377,9 @@ _PyThreadState_DeleteExcept(_PyRuntimeState *runtime, PyThreadState *tstate) } -PyThreadState * -_PyThreadState_UncheckedGet(void) -{ - return current_fast_get(&_PyRuntime); -} - - -PyThreadState * -PyThreadState_Get(void) -{ - PyThreadState *tstate = current_fast_get(&_PyRuntime); - _Py_EnsureTstateNotNULL(tstate); - return tstate; -} - - -PyThreadState * -_PyThreadState_Swap(_PyRuntimeState *runtime, PyThreadState *newts) -{ - PyThreadState *oldts = current_fast_get(runtime); - - if (newts == NULL) { - current_fast_clear(runtime); - } - else { - current_fast_set(runtime, 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. - */ - // XXX The above isn't true when multiple interpreters are involved. -#if defined(Py_DEBUG) - if (newts && current_tss_initialized(runtime)) { - /* This can be called from PyEval_RestoreThread(). Similar - to it, we need to ensure errno doesn't change. - */ - int err = errno; - PyThreadState *check = current_tss_get(runtime); - if (check && check->interp == newts->interp && check != newts) { - Py_FatalError("Invalid thread state for this thread"); - } - errno = err; - } -#endif - return oldts; -} - -PyThreadState * -PyThreadState_Swap(PyThreadState *newts) -{ - return _PyThreadState_Swap(&_PyRuntime, newts); -} +//---------- +// accessors +//---------- /* An extension mechanism to store arbitrary additional per-thread state. PyThreadState_GetDict() returns a dictionary that can be used to hold such @@ -1523,6 +1444,10 @@ PyThreadState_GetID(PyThreadState *tstate) } +//---------- +// other API +//---------- + /* Asynchronously raise an exception in a thread. Requested by Just van Rossum and Alex Martelli. To prevent naive misuse, you must write your own extension @@ -1531,6 +1456,8 @@ PyThreadState_GetID(PyThreadState *tstate) match any known thread id). Can be called with exc=NULL to clear an existing async exception. This raises no exceptions. */ +// XXX Move this to Python/ceval_gil.c? +// XXX Deprecate this. int PyThreadState_SetAsyncExc(unsigned long id, PyObject *exc) { @@ -1568,8 +1495,79 @@ PyThreadState_SetAsyncExc(unsigned long id, PyObject *exc) return 0; } -/* Routines for advanced debuggers, requested by David Beazley. - Don't use unless you know what you are doing! */ + +//--------------------------------- +// API for the current thread state +//--------------------------------- + +PyThreadState * +_PyThreadState_UncheckedGet(void) +{ + return current_fast_get(&_PyRuntime); +} + + +PyThreadState * +PyThreadState_Get(void) +{ + PyThreadState *tstate = current_fast_get(&_PyRuntime); + _Py_EnsureTstateNotNULL(tstate); + return tstate; +} + + +PyThreadState * +_PyThreadState_Swap(_PyRuntimeState *runtime, PyThreadState *newts) +{ + PyThreadState *oldts = current_fast_get(runtime); + + if (newts == NULL) { + current_fast_clear(runtime); + } + else { + current_fast_set(runtime, 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. + */ + // XXX The above isn't true when multiple interpreters are involved. +#if defined(Py_DEBUG) + if (newts && current_tss_initialized(runtime)) { + /* This can be called from PyEval_RestoreThread(). Similar + to it, we need to ensure errno doesn't change. + */ + int err = errno; + PyThreadState *check = current_tss_get(runtime); + if (check && check->interp == newts->interp && check != newts) { + Py_FatalError("Invalid thread state for this thread"); + } + errno = err; + } +#endif + return oldts; +} + +PyThreadState * +PyThreadState_Swap(PyThreadState *newts) +{ + return _PyThreadState_Swap(&_PyRuntime, newts); +} + + +void +_PyThreadState_Bind(PyThreadState *tstate) +{ + bind_tstate(tstate); +} + + +/***********************************/ +/* routines for advanced debuggers */ +/***********************************/ + +// (requested by David Beazley) +// Don't use unless you know what you are doing! PyInterpreterState * PyInterpreterState_Head(void) @@ -1598,6 +1596,11 @@ PyThreadState_Next(PyThreadState *tstate) { return tstate->next; } + +/********************************************/ +/* reporting execution state of all threads */ +/********************************************/ + /* The implementation of sys._current_frames(). This is intended to be called with the GIL held, as it will be when called via sys._current_frames(). It's possible it would work fine even without @@ -1659,6 +1662,11 @@ done: return result; } +/* The implementation of sys._current_exceptions(). This is intended to be + called with the GIL held, as it will be when called via + sys._current_exceptions(). It's possible it would work fine even without + the GIL held, but haven't thought enough about that. +*/ PyObject * _PyThread_CurrentExceptions(void) { @@ -1718,7 +1726,114 @@ done: return result; } + +/****************/ +/* module state */ +/****************/ + +PyObject* +PyState_FindModule(PyModuleDef* module) +{ + Py_ssize_t index = module->m_base.m_index; + PyInterpreterState *state = _PyInterpreterState_GET(); + PyObject *res; + if (module->m_slots) { + return NULL; + } + if (index == 0) + return NULL; + if (state->modules_by_index == NULL) + return NULL; + if (index >= PyList_GET_SIZE(state->modules_by_index)) + return NULL; + res = PyList_GET_ITEM(state->modules_by_index, index); + return res==Py_None ? NULL : res; +} + +int +_PyState_AddModule(PyThreadState *tstate, PyObject* module, PyModuleDef* def) +{ + if (!def) { + assert(_PyErr_Occurred(tstate)); + return -1; + } + if (def->m_slots) { + _PyErr_SetString(tstate, + PyExc_SystemError, + "PyState_AddModule called on module with slots"); + return -1; + } + + PyInterpreterState *interp = tstate->interp; + if (!interp->modules_by_index) { + interp->modules_by_index = PyList_New(0); + if (!interp->modules_by_index) { + return -1; + } + } + + while (PyList_GET_SIZE(interp->modules_by_index) <= def->m_base.m_index) { + if (PyList_Append(interp->modules_by_index, Py_None) < 0) { + return -1; + } + } + + return PyList_SetItem(interp->modules_by_index, + def->m_base.m_index, Py_NewRef(module)); +} + +int +PyState_AddModule(PyObject* module, PyModuleDef* def) +{ + if (!def) { + Py_FatalError("module definition is NULL"); + return -1; + } + + PyThreadState *tstate = current_fast_get(&_PyRuntime); + PyInterpreterState *interp = tstate->interp; + Py_ssize_t index = def->m_base.m_index; + if (interp->modules_by_index && + index < PyList_GET_SIZE(interp->modules_by_index) && + module == PyList_GET_ITEM(interp->modules_by_index, index)) + { + _Py_FatalErrorFormat(__func__, "module %p already added", module); + return -1; + } + return _PyState_AddModule(tstate, module, def); +} + +int +PyState_RemoveModule(PyModuleDef* def) +{ + PyThreadState *tstate = current_fast_get(&_PyRuntime); + PyInterpreterState *interp = tstate->interp; + + if (def->m_slots) { + _PyErr_SetString(tstate, + PyExc_SystemError, + "PyState_RemoveModule called on module with slots"); + return -1; + } + + Py_ssize_t index = def->m_base.m_index; + if (index == 0) { + Py_FatalError("invalid module index"); + } + if (interp->modules_by_index == NULL) { + Py_FatalError("Interpreters module-list not accessible."); + } + if (index > PyList_GET_SIZE(interp->modules_by_index)) { + Py_FatalError("Module index out of bounds."); + } + + return PyList_SetItem(interp->modules_by_index, index, Py_NewRef(Py_None)); +} + + +/***********************************/ /* Python "auto thread state" API. */ +/***********************************/ /* Internal initialization/finalization functions called by Py_Initialize/Py_FinalizeEx |