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content / browser / scheduler / responsiveness / watcher_unittest.cc [blame]
// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/scheduler/responsiveness/watcher.h"
#include "base/functional/bind.h"
#include "base/functional/callback.h"
#include "base/functional/callback_helpers.h"
#include "base/location.h"
#include "base/memory/raw_ptr.h"
#include "base/pending_task.h"
#include "base/run_loop.h"
#include "base/synchronization/lock.h"
#include "base/time/time.h"
#include "build/build_config.h"
#include "content/browser/scheduler/responsiveness/calculator.h"
#include "content/browser/scheduler/responsiveness/native_event_observer.h"
#include "content/public/browser/browser_task_traits.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/test/browser_task_environment.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace content {
namespace responsiveness {
namespace {
struct TaskTiming {
base::TimeTicks queue_time;
base::TimeTicks execution_start_time;
base::TimeTicks execution_finish_time;
};
class FakeCalculator : public Calculator {
public:
using Calculator::Calculator;
void TaskOrEventFinishedOnUIThread(
base::TimeTicks queue_time,
base::TimeTicks execution_start_time,
base::TimeTicks execution_finish_time) override {
execution_times_ui_.push_back(
{queue_time, execution_start_time, execution_finish_time});
}
void TaskOrEventFinishedOnIOThread(
base::TimeTicks queue_time,
base::TimeTicks execution_start_time,
base::TimeTicks execution_finish_time) override {
base::AutoLock l(io_thread_lock_);
execution_times_io_.push_back(
{queue_time, execution_start_time, execution_finish_time});
}
int NumTasksOnUIThread() {
return static_cast<int>(execution_times_ui_.size());
}
std::vector<TaskTiming>& ExecutionTimesUIThread() {
return execution_times_ui_;
}
int NumTasksOnIOThread() {
base::AutoLock l(io_thread_lock_);
return static_cast<int>(execution_times_io_.size());
}
std::vector<TaskTiming>& ExecutionTimesIOThread() {
base::AutoLock l(io_thread_lock_);
return execution_times_io_;
}
private:
std::vector<TaskTiming> execution_times_ui_;
base::Lock io_thread_lock_;
std::vector<TaskTiming> execution_times_io_;
};
class FakeMetricSource : public MetricSource {
public:
FakeMetricSource(Delegate* delegate, bool register_message_loop_observer)
: MetricSource(delegate),
register_message_loop_observer_(register_message_loop_observer) {}
~FakeMetricSource() override {}
void RegisterMessageLoopObserverUI() override {
if (register_message_loop_observer_)
MetricSource::RegisterMessageLoopObserverUI();
}
void RegisterMessageLoopObserverIO() override {
if (register_message_loop_observer_)
MetricSource::RegisterMessageLoopObserverIO();
}
std::unique_ptr<NativeEventObserver> CreateNativeEventObserver() override {
return nullptr;
}
private:
bool register_message_loop_observer_;
};
class FakeWatcher : public Watcher {
public:
std::unique_ptr<Calculator> CreateCalculator() override {
std::unique_ptr<FakeCalculator> calculator =
std::make_unique<FakeCalculator>(nullptr);
calculator_ = calculator.get();
return calculator;
}
std::unique_ptr<MetricSource> CreateMetricSource() override {
return std::make_unique<FakeMetricSource>(this,
register_message_loop_observer_);
}
FakeWatcher(bool register_message_loop_observer)
: Watcher(),
register_message_loop_observer_(register_message_loop_observer) {}
int NumTasksOnUIThread() { return calculator_->NumTasksOnUIThread(); }
std::vector<TaskTiming>& ExecutionTimesUIThread() {
return calculator_->ExecutionTimesUIThread();
}
std::vector<TaskTiming>& ExecutionTimesIOThread() {
return calculator_->ExecutionTimesIOThread();
}
int NumTasksOnIOThread() { return calculator_->NumTasksOnIOThread(); }
private:
~FakeWatcher() override {}
raw_ptr<FakeCalculator> calculator_ = nullptr;
bool register_message_loop_observer_ = false;
};
} // namespace
class ResponsivenessWatcherTest : public testing::Test {
public:
void SetUp() override {
// Watcher's constructor posts a task to IO thread, which in the unit test
// is also this thread. Regardless, we need to let those tasks finish.
watcher_ = scoped_refptr<FakeWatcher>(
new FakeWatcher(/*register_message_loop_observer=*/false));
watcher_->SetUp();
task_environment_.RunUntilIdle();
}
void TearDown() override {
watcher_->Destroy();
watcher_.reset();
}
protected:
// This member sets up BrowserThread::IO and BrowserThread::UI. It must be the
// first member, as other members may depend on these abstractions.
content::BrowserTaskEnvironment task_environment_{
content::BrowserTaskEnvironment::TimeSource::MOCK_TIME};
scoped_refptr<FakeWatcher> watcher_;
};
// Test that tasks are forwarded to calculator.
TEST_F(ResponsivenessWatcherTest, TaskForwarding) {
for (int i = 0; i < 3; ++i) {
base::PendingTask task(FROM_HERE, base::OnceClosure(),
/*queue_time=*/base::TimeTicks::Now(),
/*delayed_run_time=*/base::TimeTicks());
watcher_->WillRunTaskOnUIThread(&task,
/* was_blocked_or_low_priority= */ false);
watcher_->DidRunTaskOnUIThread(&task);
}
EXPECT_EQ(3, watcher_->NumTasksOnUIThread());
EXPECT_EQ(0, watcher_->NumTasksOnIOThread());
for (int i = 0; i < 4; ++i) {
base::PendingTask task(FROM_HERE, base::OnceClosure(),
/*queue_time=*/base::TimeTicks::Now(),
/*delayed_run_time=*/base::TimeTicks());
watcher_->WillRunTaskOnIOThread(&task,
/* was_blocked_or_low_priority= */ false);
watcher_->DidRunTaskOnIOThread(&task);
}
EXPECT_EQ(3, watcher_->NumTasksOnUIThread());
EXPECT_EQ(4, watcher_->NumTasksOnIOThread());
}
// Test that nested tasks are not forwarded to the calculator.
TEST_F(ResponsivenessWatcherTest, TaskNesting) {
base::PendingTask task1(FROM_HERE, base::OnceClosure(),
/*queue_time=*/base::TimeTicks::Now(),
/*delayed_run_time=*/base::TimeTicks());
base::PendingTask task2(FROM_HERE, base::OnceClosure(),
/*queue_time=*/base::TimeTicks::Now(),
/*delayed_run_time=*/base::TimeTicks());
task_environment_.FastForwardBy(base::Milliseconds(1));
base::PendingTask task3(FROM_HERE, base::OnceClosure(),
/*queue_time=*/base::TimeTicks::Now(),
/*delayed_run_time=*/base::TimeTicks());
const base::TimeTicks task_1_execution_start_time = base::TimeTicks::Now();
watcher_->WillRunTaskOnUIThread(&task1,
/* was_blocked_or_low_priority= */ false);
watcher_->WillRunTaskOnUIThread(&task2,
/* was_blocked_or_low_priority= */ false);
task_environment_.FastForwardBy(base::Milliseconds(1));
const base::TimeTicks task_3_execution_start_time = base::TimeTicks::Now();
EXPECT_EQ(task_1_execution_start_time + base::Milliseconds(1),
task_3_execution_start_time);
watcher_->WillRunTaskOnUIThread(&task3,
/* was_blocked_or_low_priority= */ false);
task_environment_.FastForwardBy(base::Milliseconds(1));
const base::TimeTicks task_3_execution_finish_time = base::TimeTicks::Now();
watcher_->DidRunTaskOnUIThread(&task3);
task_environment_.FastForwardBy(base::Milliseconds(1));
watcher_->DidRunTaskOnUIThread(&task2);
watcher_->DidRunTaskOnUIThread(&task1);
ASSERT_EQ(1, watcher_->NumTasksOnUIThread());
// The innermost task should be the one that is passed through, as it didn't
// cause reentrancy.
const TaskTiming task_timing = watcher_->ExecutionTimesUIThread()[0];
EXPECT_EQ(task3.queue_time, task_timing.queue_time);
EXPECT_EQ(task_3_execution_start_time, task_timing.execution_start_time);
EXPECT_EQ(task_3_execution_finish_time, task_timing.execution_finish_time);
EXPECT_EQ(0, watcher_->NumTasksOnIOThread());
}
// Test that native events use execution time instead of queue + execution time.
TEST_F(ResponsivenessWatcherTest, NativeEvents) {
const base::TimeTicks start_time = base::TimeTicks::Now();
void* opaque_identifier = reinterpret_cast<void*>(0x1234);
watcher_->WillRunEventOnUIThread(opaque_identifier);
task_environment_.FastForwardBy(base::Milliseconds(1));
const base::TimeTicks finish_time = base::TimeTicks::Now();
watcher_->DidRunEventOnUIThread(opaque_identifier);
ASSERT_EQ(1, watcher_->NumTasksOnUIThread());
const TaskTiming task_timing = watcher_->ExecutionTimesUIThread()[0];
EXPECT_EQ(task_timing.queue_time, start_time);
EXPECT_EQ(task_timing.execution_start_time, start_time);
EXPECT_EQ(task_timing.execution_finish_time, finish_time);
EXPECT_EQ(0, watcher_->NumTasksOnIOThread());
}
// Test that the queue duration of a blocked or low priority task is zero.
TEST_F(ResponsivenessWatcherTest, BlockedOrLowPriorityTask) {
base::PendingTask task(FROM_HERE, base::OnceClosure(),
/*queue_time=*/base::TimeTicks::Now(),
/*delayed_run_time=*/base::TimeTicks());
task_environment_.FastForwardBy(base::Seconds(1));
const base::TimeTicks execution_start_time = base::TimeTicks::Now();
watcher_->WillRunTaskOnUIThread(&task,
/* was_blocked_or_low_priority= */ true);
task_environment_.FastForwardBy(base::Milliseconds(1));
const base::TimeTicks execution_finish_time = base::TimeTicks::Now();
watcher_->DidRunTaskOnUIThread(&task);
ASSERT_EQ(1, watcher_->NumTasksOnUIThread());
const TaskTiming task_timing = watcher_->ExecutionTimesUIThread()[0];
// The queue time should be equal to the execution start time, to simulate
// that the task did not spend any time in a queue. This is the desired
// behavior for a task that was blocked or low priority.
EXPECT_EQ(task_timing.queue_time, execution_start_time);
EXPECT_EQ(task_timing.execution_start_time, execution_start_time);
EXPECT_EQ(task_timing.execution_finish_time, execution_finish_time);
EXPECT_EQ(0, watcher_->NumTasksOnIOThread());
}
// Test that the queue duration of a delayed task is zero.
TEST_F(ResponsivenessWatcherTest, DelayedTask) {
base::PendingTask task(FROM_HERE, base::OnceClosure(),
/*queue_time=*/base::TimeTicks::Now(),
/*delayed_run_time=*/base::TimeTicks::Now());
task_environment_.FastForwardBy(base::Seconds(1));
const base::TimeTicks execution_start_time = base::TimeTicks::Now();
watcher_->WillRunTaskOnUIThread(&task,
/* was_blocked_or_low_priority= */ false);
task_environment_.FastForwardBy(base::Milliseconds(1));
const base::TimeTicks execution_finish_time = base::TimeTicks::Now();
watcher_->DidRunTaskOnUIThread(&task);
ASSERT_EQ(1, watcher_->NumTasksOnUIThread());
const TaskTiming task_timing = watcher_->ExecutionTimesUIThread()[0];
// The queue time should be equal to the execution start time, to simulate
// that the task did not spend any time in a queue. This is the desired
// behavior for a delayed task.
EXPECT_EQ(task_timing.queue_time, execution_start_time);
EXPECT_EQ(task_timing.execution_start_time, execution_start_time);
EXPECT_EQ(task_timing.execution_finish_time, execution_finish_time);
EXPECT_EQ(0, watcher_->NumTasksOnIOThread());
}
class ResponsivenessWatcherRealIOThreadTest : public testing::Test {
public:
ResponsivenessWatcherRealIOThreadTest()
: task_environment_(content::BrowserTaskEnvironment::REAL_IO_THREAD) {}
void SetUp() override {
// Watcher's constructor posts a task to IO thread. We need to let those
// tasks finish.
watcher_ = scoped_refptr<FakeWatcher>(
new FakeWatcher(/*register_message_loop_observer=*/true));
watcher_->SetUp();
task_environment_.RunIOThreadUntilIdle();
}
void TearDown() override {
watcher_->Destroy();
watcher_.reset();
// Destroy a task onto the IO thread, which posts back to the UI thread
// to complete destruction.
task_environment_.RunIOThreadUntilIdle();
task_environment_.RunUntilIdle();
}
protected:
// This member sets up BrowserThread::IO and BrowserThread::UI. It must be the
// first member, as other members may depend on these abstractions.
content::BrowserTaskEnvironment task_environment_;
scoped_refptr<FakeWatcher> watcher_;
};
TEST_F(ResponsivenessWatcherRealIOThreadTest, MessageLoopObserver) {
// Post a do-nothing task onto the UI thread.
GetUIThreadTaskRunner({})->PostTask(FROM_HERE, base::DoNothing());
// Post a do-nothing task onto the IO thread.
content::GetIOThreadTaskRunner({})->PostTask(FROM_HERE, base::DoNothing());
// Post a task onto the IO thread that hops back to the UI thread. This
// guarantees that both of the do-nothing tasks have already been processed.
base::RunLoop run_loop;
content::GetIOThreadTaskRunner({})->PostTask(
FROM_HERE, base::BindOnce(
[](base::OnceClosure quit_closure) {
GetUIThreadTaskRunner({})->PostTask(
FROM_HERE, std::move(quit_closure));
},
run_loop.QuitClosure()));
run_loop.Run();
ASSERT_GE(watcher_->NumTasksOnUIThread(), 1);
const TaskTiming ui_thread_task_timing =
watcher_->ExecutionTimesUIThread()[0];
EXPECT_FALSE(ui_thread_task_timing.queue_time.is_null());
EXPECT_FALSE(ui_thread_task_timing.execution_start_time.is_null());
EXPECT_FALSE(ui_thread_task_timing.execution_finish_time.is_null());
ASSERT_GE(watcher_->NumTasksOnIOThread(), 1);
const TaskTiming io_thread_task_timing =
watcher_->ExecutionTimesUIThread()[0];
EXPECT_FALSE(io_thread_task_timing.queue_time.is_null());
EXPECT_FALSE(io_thread_task_timing.execution_start_time.is_null());
EXPECT_FALSE(io_thread_task_timing.execution_finish_time.is_null());
}
} // namespace responsiveness
} // namespace content