gh-116396: Pass "detached_state" argument to tstate_set_detached (#116398)

The stop-the-world code was incorrectly setting suspended threads'
states to _Py_THREAD_DETACHED instead of _Py_THREAD_SUSPENDED.

Author: colesbury

Python/pystate.c

@@ -903,7 +903,7 @@ _PyInterpreterState_Clear(PyThreadState *tstate)
 
 
 static inline void tstate_deactivate(PyThreadState *tstate);
-static void tstate_set_detached(PyThreadState *tstate);
+static void tstate_set_detached(PyThreadState *tstate, int detached_state);
 static void zapthreads(PyInterpreterState *interp);
 
 void
@@ -1686,7 +1686,7 @@ _PyThreadState_DeleteCurrent(PyThreadState *tstate)
 #ifdef Py_GIL_DISABLED
     _Py_qsbr_detach(((_PyThreadStateImpl *)tstate)->qsbr);
 #endif
-    tstate_set_detached(tstate);
+    tstate_set_detached(tstate, _Py_THREAD_DETACHED);
     tstate_delete_common(tstate);
     current_fast_clear(tstate->interp->runtime);
     _PyEval_ReleaseLock(tstate->interp, NULL);
@@ -1859,13 +1859,13 @@ tstate_try_attach(PyThreadState *tstate)
 }
 
 static void
-tstate_set_detached(PyThreadState *tstate)
+tstate_set_detached(PyThreadState *tstate, int detached_state)
 {
     assert(tstate->state == _Py_THREAD_ATTACHED);
 #ifdef Py_GIL_DISABLED
-    _Py_atomic_store_int(&tstate->state, _Py_THREAD_DETACHED);
+    _Py_atomic_store_int(&tstate->state, detached_state);
 #else
-    tstate->state = _Py_THREAD_DETACHED;
+    tstate->state = detached_state;
 #endif
 }
 
@@ -1935,7 +1935,7 @@ detach_thread(PyThreadState *tstate, int detached_state)
     _Py_qsbr_detach(((_PyThreadStateImpl *)tstate)->qsbr);
 #endif
     tstate_deactivate(tstate);
-    tstate_set_detached(tstate);
+    tstate_set_detached(tstate, detached_state);
     current_fast_clear(&_PyRuntime);
     _PyEval_ReleaseLock(tstate->interp, tstate);
 }