Merge "Tweak wakeup time for OneShotTimer to reduce jank" into tm-dev (57a40d9d) · Commits · e / os / android_frameworks_native-old

services/surfaceflinger/Scheduler/OneShotTimer.cpp

+12 −11

Original line number	Diff line number	Diff line
		@@ -118,17 +118,18 @@ void OneShotTimer::loop() {
		auto triggerTime = mClock->now() + mInterval;
		state = TimerState::WAITING;
		while (true) {
		// Wait until triggerTime time to check if we need to reset or drop into the idle state.
		if (const auto triggerInterval = triggerTime - mClock->now(); triggerInterval > 0ns) {
		mWaiting = true;
		constexpr auto zero = std::chrono::steady_clock::duration::zero();
		// Wait for mInterval time to check if we need to reset or drop into the idle state.
		struct timespec ts;
		calculateTimeoutTime(std::chrono::nanoseconds(mInterval), &ts);
		calculateTimeoutTime(triggerInterval, &ts);
		int result = sem_clockwait(&mSemaphore, CLOCK_MONOTONIC, &ts);
		if (result && errno != ETIMEDOUT && errno != EINTR) {
		std::stringstream ss;
		ss << "sem_clockwait failed (" << errno << ")";
		LOG_ALWAYS_FATAL("%s", ss.str().c_str());
		}
		}

		mWaiting = false;
		state = checkForResetAndStop(state);
		@@ -136,7 +137,7 @@ void OneShotTimer::loop() {
		break;
		}

		if (state == TimerState::WAITING && (triggerTime - mClock->now()) <= zero) {
		if (state == TimerState::WAITING && (triggerTime - mClock->now()) <= 0ns) {
		triggerTimeout = true;
		state = TimerState::IDLE;
		break;

services/surfaceflinger/tests/unittests/OneShotTimerTest.cpp

+34 −0

Original line number	Diff line number	Diff line
		@@ -130,6 +130,40 @@ TEST_F(OneShotTimerTest, DISABLED_resetBackToBackTest) {
		EXPECT_FALSE(mResetTimerCallback.waitForUnexpectedCall().has_value());
		}

		// TODO(b/186417847) This test is new and passes locally, but may be flaky
		TEST_F(OneShotTimerTest, DISABLED_resetBackToBackSlowAdvanceTest) {
		fake::FakeClock* clock = new fake::FakeClock();
		mIdleTimer = std::make_unique<scheduler::OneShotTimer>("TestTimer", 1ms,
		mResetTimerCallback.getInvocable(),
		mExpiredTimerCallback.getInvocable(),
		std::unique_ptr<fake::FakeClock>(clock));
		mIdleTimer->start();
		EXPECT_TRUE(mResetTimerCallback.waitForCall().has_value());

		mIdleTimer->reset();
		EXPECT_FALSE(mResetTimerCallback.waitForUnexpectedCall().has_value());
		EXPECT_FALSE(mExpiredTimerCallback.waitForUnexpectedCall().has_value());

		clock->advanceTime(200us);
		mIdleTimer->reset();

		// Normally we would check that the timer callbacks weren't invoked here
		// after resetting the timer, but we need to precisely control the timing of
		// this test, and checking that callbacks weren't invoked requires non-zero
		// time.

		clock->advanceTime(1500us);
		EXPECT_TRUE(mExpiredTimerCallback.waitForCall(1100us).has_value());
		mIdleTimer->reset();
		EXPECT_TRUE(mResetTimerCallback.waitForCall().has_value());

		mIdleTimer->stop();
		clock->advanceTime(2ms);
		// Final quick check that no more callback were observed.
		EXPECT_FALSE(mExpiredTimerCallback.waitForUnexpectedCall().has_value());
		EXPECT_FALSE(mResetTimerCallback.waitForUnexpectedCall().has_value());
		}

		TEST_F(OneShotTimerTest, startNotCalledTest) {
		fake::FakeClock* clock = new fake::FakeClock();
		mIdleTimer = std::make_unique<scheduler::OneShotTimer>("TestTimer", 1ms,