/* Copyright 2015 The TensorFlow Authors. All Rights Reserved.
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
you may not use this file except in compliance with the License.
|
You may obtain a copy of the License at
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
Unless required by applicable law or agreed to in writing, software
|
distributed under the License is distributed on an "AS IS" BASIS,
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
See the License for the specific language governing permissions and
|
limitations under the License.
|
==============================================================================*/
|
|
// The utility to read checkpoints for google brain tensor ops and v3
|
// checkpoints for dist_belief.
|
|
#ifndef TENSORFLOW_CORE_UTIL_TENSOR_SLICE_READER_CACHE_H_
|
#define TENSORFLOW_CORE_UTIL_TENSOR_SLICE_READER_CACHE_H_
|
|
#include <unordered_map>
|
|
#include "tensorflow/core/lib/core/status.h"
|
#include "tensorflow/core/platform/mutex.h"
|
#include "tensorflow/core/platform/types.h"
|
#include "tensorflow/core/util/tensor_slice_reader.h"
|
|
namespace tensorflow {
|
|
namespace checkpoint {
|
|
class TensorSliceReaderCache;
|
|
// Wrapper to a lazily allocated TensorSliceReaderCache.
|
class TensorSliceReaderCacheWrapper {
|
public:
|
TensorSliceReaderCacheWrapper();
|
~TensorSliceReaderCacheWrapper();
|
|
// Same as TensorSliceReaderCache::GetReader().
|
const TensorSliceReader* GetReader(
|
const string& filepattern,
|
TensorSliceReader::OpenTableFunction open_function,
|
int preferred_shard) const;
|
|
private:
|
mutable mutex mu_;
|
mutable TensorSliceReaderCache* cache_ = nullptr;
|
};
|
|
// A cache of TensorSliceReaders.
|
class TensorSliceReaderCache {
|
public:
|
TensorSliceReaderCache();
|
~TensorSliceReaderCache();
|
|
// Returns the TensorSliceReader corresponding to 'filepattern' and the
|
// open_function. May return nullptr if we can not create a new
|
// TensorSliceReader for the filepattern/open_function combination.
|
const TensorSliceReader* GetReader(
|
const string& filepattern,
|
TensorSliceReader::OpenTableFunction open_function, int preferred_shard);
|
|
private:
|
// Need to use a regular function type in the key map as std::function does
|
// not support ==.
|
typedef Status (*OpenFuncType)(const string&, TensorSliceReader::Table**);
|
|
// Protects attributes below.
|
mutex mu_;
|
|
// Maps of opened readers.
|
std::unordered_map<string, std::pair<OpenFuncType, TensorSliceReader*>>
|
readers_;
|
|
// Set of keys that a previous GetReader() call is still trying to populate.
|
std::set<string> still_opening_;
|
|
// Condition variable to notify when a reader has been created.
|
condition_variable cv_;
|
};
|
|
} // namespace checkpoint
|
|
} // namespace tensorflow
|
|
#endif // TENSORFLOW_CORE_UTIL_TENSOR_SLICE_READER_CACHE_H_
|
