1 files changed, 32 insertions, 10 deletions
diff --git a/Python/pystate.c b/Python/pystate.c
index 75bd9f41e3..f14934361d 100644
--- a/Python/pystate.c
+++ b/Python/pystate.c
@@ -1863,17 +1863,11 @@ PyThreadState_Get(void)
 }
 
 
-PyThreadState *
-_PyThreadState_Swap(_PyRuntimeState *runtime, PyThreadState *newts)
+static void
+_swap_thread_states(_PyRuntimeState *runtime,
+                    PyThreadState *oldts, PyThreadState *newts)
 {
-#if defined(Py_DEBUG)
-    /* This can be called from PyEval_RestoreThread(). Similar
-       to it, we need to ensure errno doesn't change.
-    */
-    int err = errno;
-#endif
-    PyThreadState *oldts = current_fast_get(runtime);
-
+    // XXX Do this only if oldts != NULL?
     current_fast_clear(runtime);
 
     if (oldts != NULL) {
@@ -1887,6 +1881,20 @@ _PyThreadState_Swap(_PyRuntimeState *runtime, PyThreadState *newts)
         current_fast_set(runtime, newts);
         tstate_activate(newts);
     }
+}
+
+PyThreadState *
+_PyThreadState_SwapNoGIL(PyThreadState *newts)
+{
+#if defined(Py_DEBUG)
+    /* This can be called from PyEval_RestoreThread(). Similar
+       to it, we need to ensure errno doesn't change.
+    */
+    int err = errno;
+#endif
+
+    PyThreadState *oldts = current_fast_get(&_PyRuntime);
+    _swap_thread_states(&_PyRuntime, oldts, newts);
 
 #if defined(Py_DEBUG)
     errno = err;
@@ -1895,6 +1903,20 @@ _PyThreadState_Swap(_PyRuntimeState *runtime, PyThreadState *newts)
 }
 
 PyThreadState *
+_PyThreadState_Swap(_PyRuntimeState *runtime, PyThreadState *newts)
+{
+    PyThreadState *oldts = current_fast_get(runtime);
+    if (oldts != NULL) {
+        _PyEval_ReleaseLock(oldts);
+    }
+    _swap_thread_states(runtime, oldts, newts);
+    if (newts != NULL) {
+        _PyEval_AcquireLock(newts);
+    }
+    return oldts;
+}
+
+PyThreadState *
 PyThreadState_Swap(PyThreadState *newts)
 {
     return _PyThreadState_Swap(&_PyRuntime, newts);