1 /* Copyright 2015 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
16 #include "tensorflow/core/common_runtime/session_factory.h"
17
18 #include <unordered_map>
19
20 #include "tensorflow/core/lib/core/errors.h"
21 #include "tensorflow/core/lib/strings/str_util.h"
22 #include "tensorflow/core/platform/logging.h"
23 #include "tensorflow/core/platform/mutex.h"
24 #include "tensorflow/core/platform/types.h"
25 #include "tensorflow/core/protobuf/config.pb_text.h"
26 #include "tensorflow/core/public/session_options.h"
27
28 namespace tensorflow {
29 namespace {
30
get_session_factory_lock()31 static mutex* get_session_factory_lock() {
32 static mutex session_factory_lock(LINKER_INITIALIZED);
33 return &session_factory_lock;
34 }
35
36 typedef std::unordered_map<string, SessionFactory*> SessionFactories;
session_factories()37 SessionFactories* session_factories() {
38 static SessionFactories* factories = new SessionFactories;
39 return factories;
40 }
41
42 } // namespace
43
Register(const string & runtime_type,SessionFactory * factory)44 void SessionFactory::Register(const string& runtime_type,
45 SessionFactory* factory) {
46 mutex_lock l(*get_session_factory_lock());
47 if (!session_factories()->insert({runtime_type, factory}).second) {
48 LOG(ERROR) << "Two session factories are being registered "
49 << "under" << runtime_type;
50 }
51 }
52
53 namespace {
RegisteredFactoriesErrorMessageLocked()54 const string RegisteredFactoriesErrorMessageLocked() {
55 std::vector<string> factory_types;
56 for (const auto& session_factory : *session_factories()) {
57 factory_types.push_back(session_factory.first);
58 }
59 return strings::StrCat("Registered factories are {",
60 str_util::Join(factory_types, ", "), "}.");
61 }
SessionOptionsToString(const SessionOptions & options)62 string SessionOptionsToString(const SessionOptions& options) {
63 return strings::StrCat("target: \"", options.target,
64 "\" config: ", ProtoShortDebugString(options.config));
65 }
66 } // namespace
67
GetFactory(const SessionOptions & options,SessionFactory ** out_factory)68 Status SessionFactory::GetFactory(const SessionOptions& options,
69 SessionFactory** out_factory) {
70 mutex_lock l(*get_session_factory_lock()); // could use reader lock
71
72 std::vector<std::pair<string, SessionFactory*>> candidate_factories;
73 for (const auto& session_factory : *session_factories()) {
74 if (session_factory.second->AcceptsOptions(options)) {
75 VLOG(2) << "SessionFactory type " << session_factory.first
76 << " accepts target: " << options.target;
77 candidate_factories.push_back(session_factory);
78 } else {
79 VLOG(2) << "SessionFactory type " << session_factory.first
80 << " does not accept target: " << options.target;
81 }
82 }
83
84 if (candidate_factories.size() == 1) {
85 *out_factory = candidate_factories[0].second;
86 return Status::OK();
87 } else if (candidate_factories.size() > 1) {
88 // NOTE(mrry): This implementation assumes that the domains (in
89 // terms of acceptable SessionOptions) of the registered
90 // SessionFactory implementations do not overlap. This is fine for
91 // now, but we may need an additional way of distinguishing
92 // different runtimes (such as an additional session option) if
93 // the number of sessions grows.
94 // TODO(mrry): Consider providing a system-default fallback option
95 // in this case.
96 std::vector<string> factory_types;
97 factory_types.reserve(candidate_factories.size());
98 for (const auto& candidate_factory : candidate_factories) {
99 factory_types.push_back(candidate_factory.first);
100 }
101 return errors::Internal(
102 "Multiple session factories registered for the given session "
103 "options: {",
104 SessionOptionsToString(options), "} Candidate factories are {",
105 str_util::Join(factory_types, ", "), "}. ",
106 RegisteredFactoriesErrorMessageLocked());
107 } else {
108 return errors::NotFound(
109 "No session factory registered for the given session options: {",
110 SessionOptionsToString(options), "} ",
111 RegisteredFactoriesErrorMessageLocked());
112 }
113 }
114
115 } // namespace tensorflow
116