Put back the SIMPLE_GIL ifdef

Author: b-pass

include/pybind11/detail/internals.h

@@ -445,6 +445,9 @@ inline uint64_t round_up_to_next_pow2(uint64_t x) {
 
 template <typename InternalsType>
 inline InternalsType **find_or_create_internals_pp(char const *state_dict_key) {
+#if defined(PYBIND11_SIMPLE_GIL_MANAGEMENT)
+    gil_scoped_acquire gil;
+#else
     // Ensure that the GIL is held since we will need to make Python calls.
     // Cannot use py::gil_scoped_acquire here since that constructor calls get_internals.
     struct gil_scoped_acquire_local {
@@ -454,6 +457,7 @@ inline InternalsType **find_or_create_internals_pp(char const *state_dict_key) {
         ~gil_scoped_acquire_local() { PyGILState_Release(state); }
         const PyGILState_STATE state;
     } gil;
+#endif
 
     error_scope err_scope;