support data_ptr() on global tensors

oneflow/api/python/framework/tensor.cpp

@@ -400,8 +400,10 @@ static PyObject* PyTensorObject_check_meta_consistency(PyObject* self, PyObject*
 static PyObject* PyTensorObject_data_ptr(PyObject* self, PyObject* unused) {
   HANDLE_ERRORS
   const auto& t = PyTensor_Unpack(self);
+  const std::shared_ptr<LocalTensor> local_tensor =
+      t->is_local() ? ASSERT_PTR(t->AsLocalTensor()) : ASSERT_PTR(t->cur_rank_phy_tensor());
   return functional::CastToPyObject(
-      reinterpret_cast<int64_t>(ASSERT(GetTensorDataPtr(ASSERT_PTR(t->AsLocalTensor())))));
+      reinterpret_cast<int64_t>(ASSERT(GetTensorDataPtr(local_tensor))));
   END_HANDLE_ERRORS
 }
 

python/oneflow/test/tensor/test_data_ptr.py

@@ -18,8 +18,8 @@
 import oneflow.unittest
 
 
-@flow.unittest.skip_unless_1n1d()
 class TestDataPtr(unittest.TestCase):
+    @flow.unittest.skip_unless_1n1d()
     def test_equality(test_case):
         x = flow.ones(2, 3)
         y = flow.ones(2, 3)
@@ -31,6 +31,13 @@ def test_equality(test_case):
         x[:] = 2
         test_case.assertEqual(x_ptr, x.data_ptr())
 
+    @flow.unittest.skip_unless_1n2d()
+    def test_global_tensor(test_case):
+        x = flow.randn(
+            2, 3, placement=flow.placement.all("cpu"), sbp=flow.sbp.broadcast
+        )
+        test_case.assertEqual(x.data_ptr(), x.to_local().data_ptr())
+
 
 if __name__ == "__main__":
     unittest.main()