6 files changed, 41 insertions, 182 deletions

diff --git a/Python/ceval_gil.c b/Python/ceval_gil.c
index 92c4b2f..636e4db 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 21b96ef..f74fee3 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(&registry->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(&registry->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 ef81f46..2dd95d8 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 20bfe1a..45a119f 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 c759916..1a7c0c9 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 46878c7..57dc4a1 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;
 }