1 /*
2 * Copyright 2019 The WebRTC Project Authors. All rights reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10 #include "api/task_queue/task_queue_test.h"
11
12 #include "absl/memory/memory.h"
13 #include "absl/strings/string_view.h"
14 #include "rtc_base/event.h"
15 #include "rtc_base/ref_counter.h"
16 #include "rtc_base/task_utils/to_queued_task.h"
17 #include "rtc_base/time_utils.h"
18
19 namespace webrtc {
20 namespace {
21
CreateTaskQueue(const std::unique_ptr<webrtc::TaskQueueFactory> & factory,absl::string_view task_queue_name,TaskQueueFactory::Priority priority=TaskQueueFactory::Priority::NORMAL)22 std::unique_ptr<TaskQueueBase, TaskQueueDeleter> CreateTaskQueue(
23 const std::unique_ptr<webrtc::TaskQueueFactory>& factory,
24 absl::string_view task_queue_name,
25 TaskQueueFactory::Priority priority = TaskQueueFactory::Priority::NORMAL) {
26 return factory->CreateTaskQueue(task_queue_name, priority);
27 }
28
TEST_P(TaskQueueTest,Construct)29 TEST_P(TaskQueueTest, Construct) {
30 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
31 auto queue = CreateTaskQueue(factory, "Construct");
32 EXPECT_FALSE(queue->IsCurrent());
33 }
34
TEST_P(TaskQueueTest,PostAndCheckCurrent)35 TEST_P(TaskQueueTest, PostAndCheckCurrent) {
36 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
37 rtc::Event event;
38 auto queue = CreateTaskQueue(factory, "PostAndCheckCurrent");
39
40 // We're not running a task, so |queue| shouldn't be current.
41 // Note that because rtc::Thread also supports the TQ interface and
42 // TestMainImpl::Init wraps the main test thread (bugs.webrtc.org/9714), that
43 // means that TaskQueueBase::Current() will still return a valid value.
44 EXPECT_FALSE(queue->IsCurrent());
45
46 queue->PostTask(ToQueuedTask([&event, &queue] {
47 EXPECT_TRUE(queue->IsCurrent());
48 event.Set();
49 }));
50 EXPECT_TRUE(event.Wait(1000));
51 }
52
TEST_P(TaskQueueTest,PostCustomTask)53 TEST_P(TaskQueueTest, PostCustomTask) {
54 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
55 rtc::Event ran;
56 auto queue = CreateTaskQueue(factory, "PostCustomImplementation");
57
58 class CustomTask : public QueuedTask {
59 public:
60 explicit CustomTask(rtc::Event* ran) : ran_(ran) {}
61
62 private:
63 bool Run() override {
64 ran_->Set();
65 return false; // Do not allow the task to be deleted by the queue.
66 }
67
68 rtc::Event* const ran_;
69 } my_task(&ran);
70
71 queue->PostTask(absl::WrapUnique(&my_task));
72 EXPECT_TRUE(ran.Wait(1000));
73 }
74
TEST_P(TaskQueueTest,PostDelayedZero)75 TEST_P(TaskQueueTest, PostDelayedZero) {
76 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
77 rtc::Event event;
78 auto queue = CreateTaskQueue(factory, "PostDelayedZero");
79
80 queue->PostDelayedTask(ToQueuedTask([&event] { event.Set(); }), 0);
81 EXPECT_TRUE(event.Wait(1000));
82 }
83
TEST_P(TaskQueueTest,PostFromQueue)84 TEST_P(TaskQueueTest, PostFromQueue) {
85 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
86 rtc::Event event;
87 auto queue = CreateTaskQueue(factory, "PostFromQueue");
88
89 queue->PostTask(ToQueuedTask([&event, &queue] {
90 queue->PostTask(ToQueuedTask([&event] { event.Set(); }));
91 }));
92 EXPECT_TRUE(event.Wait(1000));
93 }
94
TEST_P(TaskQueueTest,PostDelayed)95 TEST_P(TaskQueueTest, PostDelayed) {
96 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
97 rtc::Event event;
98 auto queue =
99 CreateTaskQueue(factory, "PostDelayed", TaskQueueFactory::Priority::HIGH);
100
101 int64_t start = rtc::TimeMillis();
102 queue->PostDelayedTask(ToQueuedTask([&event, &queue] {
103 EXPECT_TRUE(queue->IsCurrent());
104 event.Set();
105 }),
106 100);
107 EXPECT_TRUE(event.Wait(1000));
108 int64_t end = rtc::TimeMillis();
109 // These tests are a little relaxed due to how "powerful" our test bots can
110 // be. Most recently we've seen windows bots fire the callback after 94-99ms,
111 // which is why we have a little bit of leeway backwards as well.
112 EXPECT_GE(end - start, 90u);
113 EXPECT_NEAR(end - start, 190u, 100u); // Accept 90-290.
114 }
115
TEST_P(TaskQueueTest,PostMultipleDelayed)116 TEST_P(TaskQueueTest, PostMultipleDelayed) {
117 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
118 auto queue = CreateTaskQueue(factory, "PostMultipleDelayed");
119
120 std::vector<rtc::Event> events(100);
121 for (int i = 0; i < 100; ++i) {
122 rtc::Event* event = &events[i];
123 queue->PostDelayedTask(ToQueuedTask([event, &queue] {
124 EXPECT_TRUE(queue->IsCurrent());
125 event->Set();
126 }),
127 i);
128 }
129
130 for (rtc::Event& e : events)
131 EXPECT_TRUE(e.Wait(1000));
132 }
133
TEST_P(TaskQueueTest,PostDelayedAfterDestruct)134 TEST_P(TaskQueueTest, PostDelayedAfterDestruct) {
135 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
136 rtc::Event run;
137 rtc::Event deleted;
138 auto queue = CreateTaskQueue(factory, "PostDelayedAfterDestruct");
139 queue->PostDelayedTask(
140 ToQueuedTask([&run] { run.Set(); }, [&deleted] { deleted.Set(); }), 100);
141 // Destroy the queue.
142 queue = nullptr;
143 // Task might outlive the TaskQueue, but still should be deleted.
144 EXPECT_TRUE(deleted.Wait(1000));
145 EXPECT_FALSE(run.Wait(0)); // and should not run.
146 }
147
TEST_P(TaskQueueTest,PostAndReuse)148 TEST_P(TaskQueueTest, PostAndReuse) {
149 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
150 rtc::Event event;
151 auto post_queue = CreateTaskQueue(factory, "PostQueue");
152 auto reply_queue = CreateTaskQueue(factory, "ReplyQueue");
153
154 int call_count = 0;
155
156 class ReusedTask : public QueuedTask {
157 public:
158 ReusedTask(int* counter, TaskQueueBase* reply_queue, rtc::Event* event)
159 : counter_(*counter), reply_queue_(reply_queue), event_(*event) {
160 EXPECT_EQ(counter_, 0);
161 }
162
163 private:
164 bool Run() override {
165 if (++counter_ == 1) {
166 reply_queue_->PostTask(absl::WrapUnique(this));
167 // At this point, the object is owned by reply_queue_ and it's
168 // theoratically possible that the object has been deleted (e.g. if
169 // posting wasn't possible). So, don't touch any member variables here.
170
171 // Indicate to the current queue that ownership has been transferred.
172 return false;
173 } else {
174 EXPECT_EQ(counter_, 2);
175 EXPECT_TRUE(reply_queue_->IsCurrent());
176 event_.Set();
177 return true; // Indicate that the object should be deleted.
178 }
179 }
180
181 int& counter_;
182 TaskQueueBase* const reply_queue_;
183 rtc::Event& event_;
184 };
185
186 auto task =
187 std::make_unique<ReusedTask>(&call_count, reply_queue.get(), &event);
188 post_queue->PostTask(std::move(task));
189 EXPECT_TRUE(event.Wait(1000));
190 }
191
TEST_P(TaskQueueTest,PostALot)192 TEST_P(TaskQueueTest, PostALot) {
193 // Waits until DecrementCount called |count| times. Thread safe.
194 class BlockingCounter {
195 public:
196 explicit BlockingCounter(int initial_count) : count_(initial_count) {}
197
198 void DecrementCount() {
199 if (count_.DecRef() == rtc::RefCountReleaseStatus::kDroppedLastRef) {
200 event_.Set();
201 }
202 }
203 bool Wait(int give_up_after_ms) { return event_.Wait(give_up_after_ms); }
204
205 private:
206 webrtc_impl::RefCounter count_;
207 rtc::Event event_;
208 };
209
210 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
211 static constexpr int kTaskCount = 0xffff;
212 rtc::Event posting_done;
213 BlockingCounter all_destroyed(kTaskCount);
214
215 int tasks_executed = 0;
216 auto task_queue = CreateTaskQueue(factory, "PostALot");
217
218 task_queue->PostTask(ToQueuedTask([&] {
219 // Post tasks from the queue to guarantee that the 1st task won't be
220 // executed before the last one is posted.
221 for (int i = 0; i < kTaskCount; ++i) {
222 task_queue->PostTask(ToQueuedTask(
223 [&] { ++tasks_executed; }, [&] { all_destroyed.DecrementCount(); }));
224 }
225
226 posting_done.Set();
227 }));
228
229 // Before destroying the task queue wait until all child tasks are posted.
230 posting_done.Wait(rtc::Event::kForever);
231 // Destroy the task queue.
232 task_queue = nullptr;
233
234 // Expect all tasks are destroyed eventually. In some task queue
235 // implementations that might happen on a different thread after task queue is
236 // destroyed.
237 EXPECT_TRUE(all_destroyed.Wait(60000));
238 EXPECT_LE(tasks_executed, kTaskCount);
239 }
240
241 // Test posting two tasks that have shared state not protected by a
242 // lock. The TaskQueue should guarantee memory read-write order and
243 // FIFO task execution order, so the second task should always see the
244 // changes that were made by the first task.
245 //
246 // If the TaskQueue doesn't properly synchronize the execution of
247 // tasks, there will be a data race, which is undefined behavior. The
248 // EXPECT calls may randomly catch this, but to make the most of this
249 // unit test, run it under TSan or some other tool that is able to
250 // directly detect data races.
TEST_P(TaskQueueTest,PostTwoWithSharedUnprotectedState)251 TEST_P(TaskQueueTest, PostTwoWithSharedUnprotectedState) {
252 std::unique_ptr<webrtc::TaskQueueFactory> factory = GetParam()();
253 struct SharedState {
254 // First task will set this value to 1 and second will assert it.
255 int state = 0;
256 } state;
257
258 auto queue = CreateTaskQueue(factory, "PostTwoWithSharedUnprotectedState");
259 rtc::Event done;
260 queue->PostTask(ToQueuedTask([&state, &queue, &done] {
261 // Post tasks from queue to guarantee, that 1st task won't be
262 // executed before the second one will be posted.
263 queue->PostTask(ToQueuedTask([&state] { state.state = 1; }));
264 queue->PostTask(ToQueuedTask([&state, &done] {
265 EXPECT_EQ(state.state, 1);
266 done.Set();
267 }));
268 // Check, that state changing tasks didn't start yet.
269 EXPECT_EQ(state.state, 0);
270 }));
271 EXPECT_TRUE(done.Wait(1000));
272 }
273
274 // TaskQueueTest is a set of tests for any implementation of the TaskQueueBase.
275 // Tests are instantiated next to the concrete implementation(s).
276 // https://github.com/google/googletest/blob/master/googletest/docs/advanced.md#creating-value-parameterized-abstract-tests
277 GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(TaskQueueTest);
278
279 } // namespace
280 } // namespace webrtc
281