fix [#27683] Blender hangs when baking a particle system when a driver is present

3 files changed, 7 insertions, 5 deletions

diff --git a/source/blender/python/generic/py_capi_utils.c b/source/blender/python/generic/py_capi_utils.c
index 801e44bd008..81aea8571f8 100644
--- a/source/blender/python/generic/py_capi_utils.c
+++ b/source/blender/python/generic/py_capi_utils.c
@@ -36,8 +36,6 @@
 #include "BLI_path_util.h"
 #endif
 
-#define PYC_INTERPRETER_ACTIVE (((PyThreadState*)_Py_atomic_load_relaxed(&_PyThreadState_Current)) != NULL)
-
 /* array utility function */
 int PyC_AsArray(void *array, PyObject *value, const int length, const PyTypeObject *type, const short is_double, const char *error_prefix)
 {
diff --git a/source/blender/python/generic/py_capi_utils.h b/source/blender/python/generic/py_capi_utils.h
index bf2eb175882..96c93ab71f8 100644
--- a/source/blender/python/generic/py_capi_utils.h
+++ b/source/blender/python/generic/py_capi_utils.h
@@ -50,4 +50,6 @@ void PyC_MainModule_Restore(PyObject *main_mod);
 
 void PyC_SetHomePath(const char *py_path_bundle);
 
+#define PYC_INTERPRETER_ACTIVE (((PyThreadState*)_Py_atomic_load_relaxed(&_PyThreadState_Current)) != NULL)
+
 #endif // PY_CAPI_UTILS_H
diff --git a/source/blender/python/intern/bpy_driver.c b/source/blender/python/intern/bpy_driver.c
index dec393bd1e4..bcd5df97c2c 100644
--- a/source/blender/python/intern/bpy_driver.c
+++ b/source/blender/python/intern/bpy_driver.c
@@ -41,6 +41,8 @@
 
 #include "bpy_driver.h"
 
+#include "../generic/py_capi_utils.h"
+
 /* for pydrivers (drivers using one-line Python expressions to express relationships between targets) */
 PyObject *bpy_pydriver_Dict= NULL;
 
@@ -87,7 +89,7 @@ int bpy_pydriver_create_dict(void)
 void BPY_driver_reset(void)
 {
 	PyGILState_STATE gilstate;
-	int use_gil= 1; // (PyThreadState_Get()==NULL);
+	int use_gil= !PYC_INTERPRETER_ACTIVE;
 
 	if(use_gil)
 		gilstate= PyGILState_Ensure();
@@ -120,7 +122,7 @@ static void pydriver_error(ChannelDriver *driver)
  *
  * note: PyGILState_Ensure() isnt always called because python can call the
  * bake operator which intern starts a thread which calls scene update which
- * does a driver update. to avoid a deadlock check PyThreadState_Get() if PyGILState_Ensure() is needed.
+ * does a driver update. to avoid a deadlock check PYC_INTERPRETER_ACTIVE if PyGILState_Ensure() is needed.
  */
 float BPY_driver_exec(ChannelDriver *driver)
 {
@@ -147,7 +149,7 @@ float BPY_driver_exec(ChannelDriver *driver)
 		return 0.0f;
 	}
 
-	use_gil= 1; //(PyThreadState_Get()==NULL);
+	use_gil= !PYC_INTERPRETER_ACTIVE;
 
 	if(use_gil)
 		gilstate= PyGILState_Ensure();