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 __future__ import absolute_import 18from __future__ import division 19from __future__ import print_function 20 21from tensorflow.python import pywrap_tfe 22 23 24class CancellationManager(object): 25 """A mechanism for cancelling blocking computation.""" 26 27 __slots__ = ["_impl"] 28 29 def __init__(self): 30 self._impl = pywrap_tfe.TFE_NewCancellationManager() 31 32 @property 33 def is_cancelled(self): 34 """Returns `True` if `CancellationManager.start_cancel` has been called.""" 35 return pywrap_tfe.TFE_CancellationManagerIsCancelled(self._impl) 36 37 def start_cancel(self): 38 """Cancels blocking operations that have been registered with this object.""" 39 pywrap_tfe.TFE_CancellationManagerStartCancel(self._impl) 40 41 def get_cancelable_function(self, concrete_function): 42 # pylint: disable=protected-access 43 return concrete_function._experimental_with_cancellation_manager(self) 44