[tf.py_func()] Check Python interpreter state before call

Attempting to acquire the GIL in a destructor when the process is terminating can fail, leading to a hang. Fixes #21277.

1 files changed, 5 insertions, 0 deletions

diff --git a/tensorflow/python/lib/core/py_func.cc b/tensorflow/python/lib/core/py_func.cc
index 57139986af..8c1fa31f05 100644
--- a/tensorflow/python/lib/core/py_func.cc
+++ b/tensorflow/python/lib/core/py_func.cc
@@ -500,6 +500,11 @@ class PyFuncOp : public OpKernel {
       call.ins.push_back(ctx->input(i));
     }
 
+    OP_REQUIRES(
+        ctx, Py_IsInitialized(),
+        errors::FailedPrecondition("Python interpreter state is not initialized. "
+                                   "The process may be terminated."));
+      
     PyGILState_STATE py_threadstate;
     py_threadstate = PyGILState_Ensure();
     bool log_on_error;