From cf6110ba1337cb67e5867d86e7c0e8d923a5bc8d Mon Sep 17 00:00:00 2001 From: Sam Gross Date: Thu, 7 Dec 2023 14:33:40 -0500 Subject: [PATCH] gh-111924: Use PyMutex for Runtime-global Locks. (gh-112207) This replaces some usages of PyThread_type_lock with PyMutex, which does not require memory allocation to initialize. This simplifies some of the runtime initialization and is also one step towards avoiding changing the default raw memory allocator during initialize/finalization, which can be non-thread-safe in some circumstances. --- Include/internal/pycore_atexit.h | 5 +- Include/internal/pycore_ceval.h | 3 +- Include/internal/pycore_ceval_state.h | 3 +- Include/internal/pycore_crossinterp.h | 3 +- Include/internal/pycore_import.h | 3 +- Include/internal/pycore_lock.h | 17 ++++ Include/internal/pycore_pymem.h | 5 +- Include/internal/pycore_pystate.h | 4 +- Include/internal/pycore_runtime.h | 4 +- Include/internal/pycore_unicodeobject.h | 3 +- Objects/obmalloc.c | 61 ++++-------- Objects/unicodeobject.c | 4 +- Python/ceval_gil.c | 37 ++------ Python/crossinterp.c | 29 +----- Python/import.c | 10 +- Python/pylifecycle.c | 14 +-- Python/pystate.c | 121 +++--------------------- Python/sysmodule.c | 12 +-- 18 files changed, 97 insertions(+), 241 deletions(-) diff --git a/Include/internal/pycore_atexit.h b/Include/internal/pycore_atexit.h index 3966df70e26..4dcda8f517c 100644 --- a/Include/internal/pycore_atexit.h +++ b/Include/internal/pycore_atexit.h @@ -1,5 +1,8 @@ #ifndef Py_INTERNAL_ATEXIT_H #define Py_INTERNAL_ATEXIT_H + +#include "pycore_lock.h" // PyMutex + #ifdef __cplusplus extern "C" { #endif @@ -15,7 +18,7 @@ extern "C" { typedef void (*atexit_callbackfunc)(void); struct _atexit_runtime_state { - PyThread_type_lock mutex; + PyMutex mutex; #define NEXITFUNCS 32 atexit_callbackfunc callbacks[NEXITFUNCS]; int ncallbacks; diff --git a/Include/internal/pycore_ceval.h b/Include/internal/pycore_ceval.h index 3f7ac922bdf..64fb4034669 100644 --- a/Include/internal/pycore_ceval.h +++ b/Include/internal/pycore_ceval.h @@ -41,8 +41,7 @@ PyAPI_FUNC(int) _PyEval_MakePendingCalls(PyThreadState *); #endif extern void _Py_FinishPendingCalls(PyThreadState *tstate); -extern void _PyEval_InitState(PyInterpreterState *, PyThread_type_lock); -extern void _PyEval_FiniState(struct _ceval_state *ceval); +extern void _PyEval_InitState(PyInterpreterState *); extern void _PyEval_SignalReceived(PyInterpreterState *interp); // bitwise flags: diff --git a/Include/internal/pycore_ceval_state.h b/Include/internal/pycore_ceval_state.h index 072bbcda0c3..28738980eb4 100644 --- a/Include/internal/pycore_ceval_state.h +++ b/Include/internal/pycore_ceval_state.h @@ -8,6 +8,7 @@ extern "C" { # error "this header requires Py_BUILD_CORE define" #endif +#include "pycore_lock.h" // PyMutex #include "pycore_gil.h" // struct _gil_runtime_state @@ -15,7 +16,7 @@ typedef int (*_Py_pending_call_func)(void *); struct _pending_calls { int busy; - PyThread_type_lock lock; + PyMutex mutex; /* Request for running pending calls. */ int32_t calls_to_do; #define NPENDINGCALLS 32 diff --git a/Include/internal/pycore_crossinterp.h b/Include/internal/pycore_crossinterp.h index ec9dac96292..2e6d09a49f9 100644 --- a/Include/internal/pycore_crossinterp.h +++ b/Include/internal/pycore_crossinterp.h @@ -8,6 +8,7 @@ extern "C" { # error "this header requires Py_BUILD_CORE define" #endif +#include "pycore_lock.h" // PyMutex #include "pycore_pyerrors.h" @@ -128,7 +129,7 @@ struct _xidregitem { struct _xidregistry { int global; /* builtin types or heap types */ int initialized; - PyThread_type_lock mutex; + PyMutex mutex; struct _xidregitem *head; }; diff --git a/Include/internal/pycore_import.h b/Include/internal/pycore_import.h index 117e46bb862..c84f87a831b 100644 --- a/Include/internal/pycore_import.h +++ b/Include/internal/pycore_import.h @@ -9,6 +9,7 @@ extern "C" { # error "this header requires Py_BUILD_CORE define" #endif +#include "pycore_lock.h" // PyMutex #include "pycore_hashtable.h" // _Py_hashtable_t #include "pycore_time.h" // _PyTime_t @@ -47,7 +48,7 @@ struct _import_runtime_state { Py_ssize_t last_module_index; struct { /* A lock to guard the cache. */ - PyThread_type_lock mutex; + PyMutex mutex; /* The actual cache of (filename, name, PyModuleDef) for modules. Only legacy (single-phase init) extension modules are added and only if they support multiple initialization (m_size >- 0) diff --git a/Include/internal/pycore_lock.h b/Include/internal/pycore_lock.h index f135cbbc375..03ad1c9fd58 100644 --- a/Include/internal/pycore_lock.h +++ b/Include/internal/pycore_lock.h @@ -92,6 +92,13 @@ PyMutex_IsLocked(PyMutex *m) return (_Py_atomic_load_uint8(&m->v) & _Py_LOCKED) != 0; } +// Re-initializes the mutex after a fork to the unlocked state. +static inline void +_PyMutex_at_fork_reinit(PyMutex *m) +{ + memset(m, 0, sizeof(*m)); +} + typedef enum _PyLockFlags { // Do not detach/release the GIL when waiting on the lock. _Py_LOCK_DONT_DETACH = 0, @@ -108,6 +115,16 @@ typedef enum _PyLockFlags { extern PyLockStatus _PyMutex_LockTimed(PyMutex *m, _PyTime_t timeout_ns, _PyLockFlags flags); +// Lock a mutex with aditional options. See _PyLockFlags for details. +static inline void +PyMutex_LockFlags(PyMutex *m, _PyLockFlags flags) +{ + uint8_t expected = _Py_UNLOCKED; + if (!_Py_atomic_compare_exchange_uint8(&m->v, &expected, _Py_LOCKED)) { + _PyMutex_LockTimed(m, -1, flags); + } +} + // Unlock a mutex, returns 0 if the mutex is not locked (used for improved // error messages). extern int _PyMutex_TryUnlock(PyMutex *m); diff --git a/Include/internal/pycore_pymem.h b/Include/internal/pycore_pymem.h index 6b5113714db..8631ca34a5e 100644 --- a/Include/internal/pycore_pymem.h +++ b/Include/internal/pycore_pymem.h @@ -1,5 +1,8 @@ #ifndef Py_INTERNAL_PYMEM_H #define Py_INTERNAL_PYMEM_H + +#include "pycore_lock.h" // PyMutex + #ifdef __cplusplus extern "C" { #endif @@ -30,7 +33,7 @@ typedef struct { } debug_alloc_api_t; struct _pymem_allocators { - PyThread_type_lock mutex; + PyMutex mutex; struct { PyMemAllocatorEx raw; PyMemAllocatorEx mem; diff --git a/Include/internal/pycore_pystate.h b/Include/internal/pycore_pystate.h index 7fa952e371d..c031a38cd6b 100644 --- a/Include/internal/pycore_pystate.h +++ b/Include/internal/pycore_pystate.h @@ -220,9 +220,9 @@ PyAPI_FUNC(int) _PyState_AddModule( extern int _PyOS_InterruptOccurred(PyThreadState *tstate); #define HEAD_LOCK(runtime) \ - PyThread_acquire_lock((runtime)->interpreters.mutex, WAIT_LOCK) + PyMutex_LockFlags(&(runtime)->interpreters.mutex, _Py_LOCK_DONT_DETACH) #define HEAD_UNLOCK(runtime) \ - PyThread_release_lock((runtime)->interpreters.mutex) + PyMutex_Unlock(&(runtime)->interpreters.mutex) // Get the configuration of the current interpreter. // The caller must hold the GIL. diff --git a/Include/internal/pycore_runtime.h b/Include/internal/pycore_runtime.h index 36743723f8a..e3348296ea6 100644 --- a/Include/internal/pycore_runtime.h +++ b/Include/internal/pycore_runtime.h @@ -173,7 +173,7 @@ typedef struct pyruntimestate { unsigned long _finalizing_id; struct pyinterpreters { - PyThread_type_lock mutex; + PyMutex mutex; /* The linked list of interpreters, newest first. */ PyInterpreterState *head; /* The runtime's initial interpreter, which has a special role @@ -234,7 +234,7 @@ typedef struct pyruntimestate { Py_OpenCodeHookFunction open_code_hook; void *open_code_userdata; struct { - PyThread_type_lock mutex; + PyMutex mutex; _Py_AuditHookEntry *head; } audit_hooks; diff --git a/Include/internal/pycore_unicodeobject.h b/Include/internal/pycore_unicodeobject.h index a0d00af92e0..7ee540154b2 100644 --- a/Include/internal/pycore_unicodeobject.h +++ b/Include/internal/pycore_unicodeobject.h @@ -8,6 +8,7 @@ extern "C" { # error "this header requires Py_BUILD_CORE define" #endif +#include "pycore_lock.h" // PyMutex #include "pycore_fileutils.h" // _Py_error_handler #include "pycore_identifier.h" // _Py_Identifier #include "pycore_ucnhash.h" // _PyUnicode_Name_CAPI @@ -277,7 +278,7 @@ extern PyTypeObject _PyUnicodeASCIIIter_Type; /* --- Other API ---------------------------------------------------------- */ struct _Py_unicode_runtime_ids { - PyThread_type_lock lock; + PyMutex mutex; // next_index value must be preserved when Py_Initialize()/Py_Finalize() // is called multiple times: see _PyUnicode_FromId() implementation. Py_ssize_t next_index; diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c index 2761c774209..b737c030957 100644 --- a/Objects/obmalloc.c +++ b/Objects/obmalloc.c @@ -329,13 +329,9 @@ int _PyMem_SetDefaultAllocator(PyMemAllocatorDomain domain, PyMemAllocatorEx *old_alloc) { - if (ALLOCATORS_MUTEX == NULL) { - /* The runtime must be initializing. */ - return set_default_allocator_unlocked(domain, pydebug, old_alloc); - } - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); int res = set_default_allocator_unlocked(domain, pydebug, old_alloc); - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); return res; } @@ -467,9 +463,9 @@ set_up_allocators_unlocked(PyMemAllocatorName allocator) int _PyMem_SetupAllocators(PyMemAllocatorName allocator) { - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); int res = set_up_allocators_unlocked(allocator); - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); return res; } @@ -554,9 +550,9 @@ get_current_allocator_name_unlocked(void) const char* _PyMem_GetCurrentAllocatorName(void) { - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); const char *name = get_current_allocator_name_unlocked(); - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); return name; } @@ -653,14 +649,9 @@ set_up_debug_hooks_unlocked(void) void PyMem_SetupDebugHooks(void) { - if (ALLOCATORS_MUTEX == NULL) { - /* The runtime must not be completely initialized yet. */ - set_up_debug_hooks_unlocked(); - return; - } - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); set_up_debug_hooks_unlocked(); - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); } static void @@ -696,53 +687,33 @@ set_allocator_unlocked(PyMemAllocatorDomain domain, PyMemAllocatorEx *allocator) void PyMem_GetAllocator(PyMemAllocatorDomain domain, PyMemAllocatorEx *allocator) { - if (ALLOCATORS_MUTEX == NULL) { - /* The runtime must not be completely initialized yet. */ - get_allocator_unlocked(domain, allocator); - return; - } - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); get_allocator_unlocked(domain, allocator); - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); } void PyMem_SetAllocator(PyMemAllocatorDomain domain, PyMemAllocatorEx *allocator) { - if (ALLOCATORS_MUTEX == NULL) { - /* The runtime must not be completely initialized yet. */ - set_allocator_unlocked(domain, allocator); - return; - } - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); set_allocator_unlocked(domain, allocator); - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); } void PyObject_GetArenaAllocator(PyObjectArenaAllocator *allocator) { - if (ALLOCATORS_MUTEX == NULL) { - /* The runtime must not be completely initialized yet. */ - *allocator = _PyObject_Arena; - return; - } - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); *allocator = _PyObject_Arena; - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); } void PyObject_SetArenaAllocator(PyObjectArenaAllocator *allocator) { - if (ALLOCATORS_MUTEX == NULL) { - /* The runtime must not be completely initialized yet. */ - _PyObject_Arena = *allocator; - return; - } - PyThread_acquire_lock(ALLOCATORS_MUTEX, WAIT_LOCK); + PyMutex_Lock(&ALLOCATORS_MUTEX); _PyObject_Arena = *allocator; - PyThread_release_lock(ALLOCATORS_MUTEX); + PyMutex_Unlock(&ALLOCATORS_MUTEX); } diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c index 10022e23c04..836e14fd5d5 100644 --- a/Objects/unicodeobject.c +++ b/Objects/unicodeobject.c @@ -1904,7 +1904,7 @@ _PyUnicode_FromId(_Py_Identifier *id) if (index < 0) { struct _Py_unicode_runtime_ids *rt_ids = &interp->runtime->unicode_state.ids; - PyThread_acquire_lock(rt_ids->lock, WAIT_LOCK); + PyMutex_Lock(&rt_ids->mutex); // Check again to detect concurrent access. Another thread can have // initialized the index while this thread waited for the lock. index = _Py_atomic_load_ssize(&id->index); @@ -1914,7 +1914,7 @@ _PyUnicode_FromId(_Py_Identifier *id) rt_ids->next_index++; _Py_atomic_store_ssize(&id->index, index); } - PyThread_release_lock(rt_ids->lock); + PyMutex_Unlock(&rt_ids->mutex); } assert(index >= 0); diff --git a/Python/ceval_gil.c b/Python/ceval_gil.c index 92c4b2fee9f..636e4db898f 100644 --- a/Python/ceval_gil.c +++ b/Python/ceval_gil.c @@ -589,9 +589,7 @@ _PyEval_ReInitThreads(PyThreadState *tstate) take_gil(tstate); struct _pending_calls *pending = &tstate->interp->ceval.pending; - if (_PyThread_at_fork_reinit(&pending->lock) < 0) { - return _PyStatus_ERR("Can't reinitialize pending calls lock"); - } + _PyMutex_at_fork_reinit(&pending->mutex); /* Destroy all threads except the current one */ _PyThreadState_DeleteExcept(tstate); @@ -720,13 +718,10 @@ _PyEval_AddPendingCall(PyInterpreterState *interp, assert(_Py_IsMainInterpreter(interp)); pending = &_PyRuntime.ceval.pending_mainthread; } - /* Ensure that _PyEval_InitState() was called - and that _PyEval_FiniState() is not called yet. */ - assert(pending->lock != NULL); - PyThread_acquire_lock(pending->lock, WAIT_LOCK); + PyMutex_Lock(&pending->mutex); int result = _push_pending_call(pending, func, arg, flags); - PyThread_release_lock(pending->lock); + PyMutex_Unlock(&pending->mutex); /* signal main loop */ SIGNAL_PENDING_CALLS(interp); @@ -768,9 +763,9 @@ _make_pending_calls(struct _pending_calls *pending) int flags = 0; /* pop one item off the queue while holding the lock */ - PyThread_acquire_lock(pending->lock, WAIT_LOCK); + PyMutex_Lock(&pending->mutex); _pop_pending_call(pending, &func, &arg, &flags); - PyThread_release_lock(pending->lock); + PyMutex_Unlock(&pending->mutex); /* having released the lock, perform the callback */ if (func == NULL) { @@ -795,7 +790,7 @@ make_pending_calls(PyInterpreterState *interp) /* Only one thread (per interpreter) may run the pending calls at once. In the same way, we don't do recursive pending calls. */ - PyThread_acquire_lock(pending->lock, WAIT_LOCK); + PyMutex_Lock(&pending->mutex); if (pending->busy) { /* A pending call was added after another thread was already handling the pending calls (and had already "unsignaled"). @@ -807,11 +802,11 @@ make_pending_calls(PyInterpreterState *interp) care of any remaining pending calls. Until then, though, all the interpreter's threads will be tripping the eval breaker every time it's checked. */ - PyThread_release_lock(pending->lock); + PyMutex_Unlock(&pending->mutex); return 0; } pending->busy = 1; - PyThread_release_lock(pending->lock); + PyMutex_Unlock(&pending->mutex); /* unsignal before starting to call callbacks, so that any callback added in-between re-signals */ @@ -892,23 +887,9 @@ Py_MakePendingCalls(void) } void -_PyEval_InitState(PyInterpreterState *interp, PyThread_type_lock pending_lock) +_PyEval_InitState(PyInterpreterState *interp) { _gil_initialize(&interp->_gil); - - struct _pending_calls *pending = &interp->ceval.pending; - assert(pending->lock == NULL); - pending->lock = pending_lock; -} - -void -_PyEval_FiniState(struct _ceval_state *ceval) -{ - struct _pending_calls *pending = &ceval->pending; - if (pending->lock != NULL) { - PyThread_free_lock(pending->lock); - pending->lock = NULL; - } } diff --git a/Python/crossinterp.c b/Python/crossinterp.c index 21b96ef05ed..f74fee38648 100644 --- a/Python/crossinterp.c +++ b/Python/crossinterp.c @@ -456,16 +456,17 @@ _xidregistry_clear(struct _xidregistry *xidregistry) static void _xidregistry_lock(struct _xidregistry *registry) { - if (registry->mutex != NULL) { - PyThread_acquire_lock(registry->mutex, WAIT_LOCK); + if (registry->global) { + PyMutex_Lock(®istry->mutex); } + // else: Within an interpreter we rely on the GIL instead of a separate lock. } static void _xidregistry_unlock(struct _xidregistry *registry) { - if (registry->mutex != NULL) { - PyThread_release_lock(registry->mutex); + if (registry->global) { + PyMutex_Unlock(®istry->mutex); } } @@ -874,19 +875,10 @@ _xidregistry_init(struct _xidregistry *registry) registry->initialized = 1; if (registry->global) { - // We manage the mutex lifecycle in pystate.c. - assert(registry->mutex != NULL); - // Registering the builtins is cheap so we don't bother doing it lazily. assert(registry->head == NULL); _register_builtins_for_crossinterpreter_data(registry); } - else { - // Within an interpreter we rely on the GIL instead of a separate lock. - assert(registry->mutex == NULL); - - // There's nothing else to initialize. - } } static void @@ -898,17 +890,6 @@ _xidregistry_fini(struct _xidregistry *registry) registry->initialized = 0; _xidregistry_clear(registry); - - if (registry->global) { - // We manage the mutex lifecycle in pystate.c. - assert(registry->mutex != NULL); - } - else { - // There's nothing else to finalize. - - // Within an interpreter we rely on the GIL instead of a separate lock. - assert(registry->mutex == NULL); - } } diff --git a/Python/import.c b/Python/import.c index ef81f46a4d6..2dd95d8364a 100644 --- a/Python/import.c +++ b/Python/import.c @@ -418,11 +418,7 @@ remove_module(PyThreadState *tstate, PyObject *name) Py_ssize_t _PyImport_GetNextModuleIndex(void) { - PyThread_acquire_lock(EXTENSIONS.mutex, WAIT_LOCK); - LAST_MODULE_INDEX++; - Py_ssize_t index = LAST_MODULE_INDEX; - PyThread_release_lock(EXTENSIONS.mutex); - return index; + return _Py_atomic_add_ssize(&LAST_MODULE_INDEX, 1) + 1; } static const char * @@ -882,13 +878,13 @@ gets even messier. static inline void extensions_lock_acquire(void) { - PyThread_acquire_lock(_PyRuntime.imports.extensions.mutex, WAIT_LOCK); + PyMutex_Lock(&_PyRuntime.imports.extensions.mutex); } static inline void extensions_lock_release(void) { - PyThread_release_lock(_PyRuntime.imports.extensions.mutex); + PyMutex_Unlock(&_PyRuntime.imports.extensions.mutex); } /* Magic for extension modules (built-in as well as dynamically diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c index 20bfe1a0b75..45a119fcca7 100644 --- a/Python/pylifecycle.c +++ b/Python/pylifecycle.c @@ -3056,13 +3056,13 @@ wait_for_thread_shutdown(PyThreadState *tstate) int Py_AtExit(void (*func)(void)) { struct _atexit_runtime_state *state = &_PyRuntime.atexit; - PyThread_acquire_lock(state->mutex, WAIT_LOCK); + PyMutex_Lock(&state->mutex); if (state->ncallbacks >= NEXITFUNCS) { - PyThread_release_lock(state->mutex); + PyMutex_Unlock(&state->mutex); return -1; } state->callbacks[state->ncallbacks++] = func; - PyThread_release_lock(state->mutex); + PyMutex_Unlock(&state->mutex); return 0; } @@ -3072,18 +3072,18 @@ call_ll_exitfuncs(_PyRuntimeState *runtime) atexit_callbackfunc exitfunc; struct _atexit_runtime_state *state = &runtime->atexit; - PyThread_acquire_lock(state->mutex, WAIT_LOCK); + PyMutex_Lock(&state->mutex); while (state->ncallbacks > 0) { /* pop last function from the list */ state->ncallbacks--; exitfunc = state->callbacks[state->ncallbacks]; state->callbacks[state->ncallbacks] = NULL; - PyThread_release_lock(state->mutex); + PyMutex_Unlock(&state->mutex); exitfunc(); - PyThread_acquire_lock(state->mutex, WAIT_LOCK); + PyMutex_Lock(&state->mutex); } - PyThread_release_lock(state->mutex); + PyMutex_Unlock(&state->mutex); fflush(stdout); fflush(stderr); diff --git a/Python/pystate.c b/Python/pystate.c index c7599166786..1a7c0c96850 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -379,49 +379,23 @@ _Py_COMP_DIAG_IGNORE_DEPR_DECLS static const _PyRuntimeState initial = _PyRuntimeState_INIT(_PyRuntime); _Py_COMP_DIAG_POP -#define NUMLOCKS 8 #define LOCKS_INIT(runtime) \ { \ &(runtime)->interpreters.mutex, \ &(runtime)->xi.registry.mutex, \ - &(runtime)->unicode_state.ids.lock, \ + &(runtime)->unicode_state.ids.mutex, \ &(runtime)->imports.extensions.mutex, \ - &(runtime)->ceval.pending_mainthread.lock, \ + &(runtime)->ceval.pending_mainthread.mutex, \ &(runtime)->atexit.mutex, \ &(runtime)->audit_hooks.mutex, \ &(runtime)->allocators.mutex, \ } -static int -alloc_for_runtime(PyThread_type_lock locks[NUMLOCKS]) -{ - /* Force default allocator, since _PyRuntimeState_Fini() must - use the same allocator than this function. */ - PyMemAllocatorEx old_alloc; - _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc); - - for (int i = 0; i < NUMLOCKS; i++) { - PyThread_type_lock lock = PyThread_allocate_lock(); - if (lock == NULL) { - for (int j = 0; j < i; j++) { - PyThread_free_lock(locks[j]); - locks[j] = NULL; - } - break; - } - locks[i] = lock; - } - - PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc); - return 0; -} - static void init_runtime(_PyRuntimeState *runtime, void *open_code_hook, void *open_code_userdata, _Py_AuditHookEntry *audit_hook_head, - Py_ssize_t unicode_next_index, - PyThread_type_lock locks[NUMLOCKS]) + Py_ssize_t unicode_next_index) { assert(!runtime->preinitializing); assert(!runtime->preinitialized); @@ -435,12 +409,6 @@ init_runtime(_PyRuntimeState *runtime, PyPreConfig_InitPythonConfig(&runtime->preconfig); - PyThread_type_lock *lockptrs[NUMLOCKS] = LOCKS_INIT(runtime); - for (int i = 0; i < NUMLOCKS; i++) { - assert(locks[i] != NULL); - *lockptrs[i] = locks[i]; - } - // Set it to the ID of the main thread of the main interpreter. runtime->main_thread = PyThread_get_thread_ident(); @@ -466,11 +434,6 @@ _PyRuntimeState_Init(_PyRuntimeState *runtime) // is called multiple times. Py_ssize_t unicode_next_index = runtime->unicode_state.ids.next_index; - PyThread_type_lock locks[NUMLOCKS]; - if (alloc_for_runtime(locks) != 0) { - return _PyStatus_NO_MEMORY(); - } - if (runtime->_initialized) { // Py_Initialize() must be running again. // Reset to _PyRuntimeState_INIT. @@ -489,7 +452,7 @@ _PyRuntimeState_Init(_PyRuntimeState *runtime) } init_runtime(runtime, open_code_hook, open_code_userdata, audit_hook_head, - unicode_next_index, locks); + unicode_next_index); return _PyStatus_OK(); } @@ -509,23 +472,6 @@ _PyRuntimeState_Fini(_PyRuntimeState *runtime) if (PyThread_tss_is_created(&runtime->trashTSSkey)) { PyThread_tss_delete(&runtime->trashTSSkey); } - - /* Force the allocator used by _PyRuntimeState_Init(). */ - PyMemAllocatorEx old_alloc; - _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc); -#define FREE_LOCK(LOCK) \ - if (LOCK != NULL) { \ - PyThread_free_lock(LOCK); \ - LOCK = NULL; \ - } - - PyThread_type_lock *lockptrs[NUMLOCKS] = LOCKS_INIT(runtime); - for (int i = 0; i < NUMLOCKS; i++) { - FREE_LOCK(*lockptrs[i]); - } - -#undef FREE_LOCK - PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc); } #ifdef HAVE_FORK @@ -537,28 +483,19 @@ _PyRuntimeState_ReInitThreads(_PyRuntimeState *runtime) // This was initially set in _PyRuntimeState_Init(). runtime->main_thread = PyThread_get_thread_ident(); - /* Force default allocator, since _PyRuntimeState_Fini() must - use the same allocator than this function. */ - PyMemAllocatorEx old_alloc; - _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc); - - PyThread_type_lock *lockptrs[NUMLOCKS] = LOCKS_INIT(runtime); - int reinit_err = 0; - for (int i = 0; i < NUMLOCKS; i++) { - reinit_err += _PyThread_at_fork_reinit(lockptrs[i]); - } - - PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc); - // Clears the parking lot. Any waiting threads are dead. This must be // called before releasing any locks that use the parking lot. _PyParkingLot_AfterFork(); + // Re-initialize global locks + PyMutex *locks[] = LOCKS_INIT(runtime); + for (size_t i = 0; i < Py_ARRAY_LENGTH(locks); i++) { + _PyMutex_at_fork_reinit(locks[i]); + } + /* bpo-42540: id_mutex is freed by _PyInterpreterState_Delete, which does * not force the default allocator. */ - reinit_err += _PyThread_at_fork_reinit(&runtime->interpreters.main->id_mutex); - - if (reinit_err < 0) { + if (_PyThread_at_fork_reinit(&runtime->interpreters.main->id_mutex) < 0) { return _PyStatus_ERR("Failed to reinitialize runtime locks"); } @@ -594,24 +531,6 @@ _PyInterpreterState_Enable(_PyRuntimeState *runtime) { struct pyinterpreters *interpreters = &runtime->interpreters; interpreters->next_id = 0; - - /* Py_Finalize() calls _PyRuntimeState_Fini() which clears the mutex. - Create a new mutex if needed. */ - if (interpreters->mutex == NULL) { - /* Force default allocator, since _PyRuntimeState_Fini() must - use the same allocator than this function. */ - PyMemAllocatorEx old_alloc; - _PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc); - - interpreters->mutex = PyThread_allocate_lock(); - - PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc); - - if (interpreters->mutex == NULL) { - return _PyStatus_ERR("Can't initialize threads for interpreter"); - } - } - return _PyStatus_OK(); } @@ -654,8 +573,7 @@ free_interpreter(PyInterpreterState *interp) static PyStatus init_interpreter(PyInterpreterState *interp, _PyRuntimeState *runtime, int64_t id, - PyInterpreterState *next, - PyThread_type_lock pending_lock) + PyInterpreterState *next) { if (interp->_initialized) { return _PyStatus_ERR("interpreter already initialized"); @@ -684,7 +602,7 @@ init_interpreter(PyInterpreterState *interp, return status; } - _PyEval_InitState(interp, pending_lock); + _PyEval_InitState(interp); _PyGC_InitState(&interp->gc); PyConfig_InitPythonConfig(&interp->config); _PyType_InitCache(interp); @@ -730,11 +648,6 @@ _PyInterpreterState_New(PyThreadState *tstate, PyInterpreterState **pinterp) } } - PyThread_type_lock pending_lock = PyThread_allocate_lock(); - if (pending_lock == NULL) { - return _PyStatus_NO_MEMORY(); - } - /* We completely serialize creation of multiple interpreters, since it simplifies things here and blocking concurrent calls isn't a problem. Regardless, we must fully block subinterpreter creation until @@ -781,11 +694,10 @@ _PyInterpreterState_New(PyThreadState *tstate, PyInterpreterState **pinterp) interpreters->head = interp; status = init_interpreter(interp, runtime, - id, old_head, pending_lock); + id, old_head); if (_PyStatus_EXCEPTION(status)) { goto error; } - pending_lock = NULL; HEAD_UNLOCK(runtime); @@ -796,9 +708,6 @@ _PyInterpreterState_New(PyThreadState *tstate, PyInterpreterState **pinterp) error: HEAD_UNLOCK(runtime); - if (pending_lock != NULL) { - PyThread_free_lock(pending_lock); - } if (interp != NULL) { free_interpreter(interp); } @@ -1003,8 +912,6 @@ PyInterpreterState_Delete(PyInterpreterState *interp) zapthreads(interp); - _PyEval_FiniState(&interp->ceval); - // XXX These two calls should be done at the end of clear_interpreter(), // but currently some objects get decref'ed after that. #ifdef Py_REF_DEBUG diff --git a/Python/sysmodule.c b/Python/sysmodule.c index 46878c7c968..57dc4a1226c 100644 --- a/Python/sysmodule.c +++ b/Python/sysmodule.c @@ -451,15 +451,9 @@ PySys_AddAuditHook(Py_AuditHookFunction hook, void *userData) e->hookCFunction = (Py_AuditHookFunction)hook; e->userData = userData; - if (runtime->audit_hooks.mutex == NULL) { - /* The runtime must not be initialized yet. */ - add_audit_hook_entry_unlocked(runtime, e); - } - else { - PyThread_acquire_lock(runtime->audit_hooks.mutex, WAIT_LOCK); - add_audit_hook_entry_unlocked(runtime, e); - PyThread_release_lock(runtime->audit_hooks.mutex); - } + PyMutex_Lock(&runtime->audit_hooks.mutex); + add_audit_hook_entry_unlocked(runtime, e); + PyMutex_Unlock(&runtime->audit_hooks.mutex); return 0; }