Merge "audio: Implement more accurate timing for the stub stream" into main (722afde6) · Commits · e / os / android_hardware_interfaces

audio/aidl/default/include/core-impl/StreamStub.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -44,6 +44,10 @@ class StreamStub : public StreamCommonImpl {
		const bool mIsInput;
		bool mIsInitialized = false; // Used for validating the state machine logic.
		bool mIsStandby = true; // Used for validating the state machine logic.

		// Used by the worker thread.
		int64_t mStartTimeNs = 0;
		long mFramesSinceStart = 0;
		};

		class StreamInStub final : public StreamIn, public StreamStub {

audio/aidl/default/stub/StreamStub.cpp

+16 −8

Original line number	Diff line number	Diff line
		@@ -83,7 +83,6 @@ StreamStub::~StreamStub() {
		if (!mIsInitialized) {
		LOG(FATAL) << __func__ << ": must not happen for an uninitialized driver";
		}
		usleep(500);
		mIsStandby = true;
		return ::android::OK;
		}
		@@ -92,8 +91,9 @@ StreamStub::~StreamStub() {
		if (!mIsInitialized) {
		LOG(FATAL) << __func__ << ": must not happen for an uninitialized driver";
		}
		usleep(500);
		mIsStandby = false;
		mStartTimeNs = ::android::uptimeNanos();
		mFramesSinceStart = 0;
		return ::android::OK;
		}

		@@ -105,14 +105,23 @@ StreamStub::~StreamStub() {
		if (mIsStandby) {
		LOG(FATAL) << __func__ << ": must not happen while in standby";
		}
		static constexpr float kMicrosPerSecond = MICROS_PER_SECOND;
		static constexpr float kScaleFactor = .8f;
		*actualFrameCount = frameCount;
		if (mIsAsynchronous) {
		usleep(500);
		} else {
		const size_t delayUs = static_cast<size_t>(
		std::roundf(kScaleFactor * frameCount * kMicrosPerSecond / mSampleRate));
		usleep(delayUs);
		mFramesSinceStart += *actualFrameCount;
		const long bufferDurationUs =
		(actualFrameCount) MICROS_PER_SECOND / mContext.getSampleRate();
		const auto totalDurationUs =
		(::android::uptimeNanos() - mStartTimeNs) / NANOS_PER_MICROSECOND;
		const long totalOffsetUs =
		mFramesSinceStart * MICROS_PER_SECOND / mContext.getSampleRate() - totalDurationUs;
		LOG(VERBOSE) << __func__ << ": totalOffsetUs " << totalOffsetUs;
		if (totalOffsetUs > 0) {
		const long sleepTimeUs = std::min(totalOffsetUs, bufferDurationUs);
		LOG(VERBOSE) << __func__ << ": sleeping for " << sleepTimeUs << " us";
		usleep(sleepTimeUs);
		}
		}
		if (mIsInput) {
		uint8_t* byteBuffer = static_cast<uint8_t*>(buffer);
		@@ -120,7 +129,6 @@ StreamStub::~StreamStub() {
		byteBuffer[i] = std::rand() % 255;
		}
		}
		*actualFrameCount = frameCount;
		return ::android::OK;
		}