1# Copyright 2019 The TensorFlow Authors. All Rights Reserved. 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# http://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12# See the License for the specific language governing permissions and 13# limitations under the License. 14# ============================================================================== 15"""Cancellation support for eager execution.""" 16 17from tensorflow.python import pywrap_tfe 18 19 20class CancellationManager(object): 21 """A mechanism for cancelling blocking computation.""" 22 23 __slots__ = ["_impl"] 24 25 def __init__(self): 26 self._impl = pywrap_tfe.TFE_NewCancellationManager() 27 28 @property 29 def is_cancelled(self): 30 """Returns `True` if `CancellationManager.start_cancel` has been called.""" 31 return pywrap_tfe.TFE_CancellationManagerIsCancelled(self._impl) 32 33 def start_cancel(self): 34 """Cancels blocking operations that have been registered with this object.""" 35 pywrap_tfe.TFE_CancellationManagerStartCancel(self._impl) 36 37 def get_cancelable_function(self, concrete_function): 38 # pylint: disable=protected-access 39 return concrete_function._experimental_with_cancellation_manager(self) 40