Merge "audioflinger: reduce sleep time to avoid underrun" into ics-mr1 (20398fac) · Commits · e / os / android_frameworks_base

services/audioflinger/AudioFlinger.cpp

+23 −1

Original line number	Diff line number	Diff line
		@@ -89,6 +89,12 @@ static const int kRecordThreadSleepUs = 5000;

		static const nsecs_t kSetParametersTimeout = seconds(2);

		// minimum sleep time for the mixer thread loop when tracks are active but in underrun
		static const uint32_t kMinThreadSleepTimeUs = 5000;
		// maximum divider applied to the active sleep time in the mixer thread loop
		static const uint32_t kMaxThreadSleepTimeShift = 2;


		// ----------------------------------------------------------------------------

		static bool recordingAllowed() {
		@@ -1846,6 +1852,7 @@ bool AudioFlinger::MixerThread::threadLoop()
		uint32_t activeSleepTime = activeSleepTimeUs();
		uint32_t idleSleepTime = idleSleepTimeUs();
		uint32_t sleepTime = idleSleepTime;
		uint32_t sleepTimeShift = 0;
		Vector< sp<EffectChain> > effectChains;
		#ifdef DEBUG_CPU_USAGE
		ThreadCpuUsage cpu;
		@@ -1937,6 +1944,7 @@ bool AudioFlinger::MixerThread::threadLoop()

		standbyTime = systemTime() + kStandbyTimeInNsecs;
		sleepTime = idleSleepTime;
		sleepTimeShift = 0;
		continue;
		}
		}
		@@ -1953,6 +1961,10 @@ bool AudioFlinger::MixerThread::threadLoop()
		// mix buffers...
		mAudioMixer->process();
		sleepTime = 0;
		// increase sleep time progressively when application underrun condition clears
		if (sleepTimeShift > 0) {
		sleepTimeShift--;
		}
		standbyTime = systemTime() + kStandbyTimeInNsecs;
		//TODO: delay standby when effects have a tail
		} else {
		@@ -1960,7 +1972,17 @@ bool AudioFlinger::MixerThread::threadLoop()
		// buffer size, then write 0s to the output
		if (sleepTime == 0) {
		if (mixerStatus == MIXER_TRACKS_ENABLED) {
		sleepTime = activeSleepTime;
		sleepTime = activeSleepTime >> sleepTimeShift;
		if (sleepTime < kMinThreadSleepTimeUs) {
		sleepTime = kMinThreadSleepTimeUs;
		}
		// reduce sleep time in case of consecutive application underruns to avoid
		// starving the audio HAL. As activeSleepTimeUs() is larger than a buffer
		// duration we would end up writing less data than needed by the audio HAL if
		// the condition persists.
		if (sleepTimeShift < kMaxThreadSleepTimeShift) {
		sleepTimeShift++;
		}
		} else {
		sleepTime = idleSleepTime;
		}