Merge "AudioFlinger: Use actual MonoPipe depth for sleep computation" into pi-dev

    // buffer size, then write 0s to the output

    if (mSleepTimeUs == 0) {

        if (mMixerStatus == MIXER_TRACKS_ENABLED) {

            if (mPipeSink.get() != nullptr && mPipeSink == mNormalSink) {

                // Using the Monopipe availableToWrite, we estimate the

                // sleep time to retry for more data (before we underrun).

                MonoPipe *monoPipe = static_cast<MonoPipe *>(mPipeSink.get());

                const ssize_t availableToWrite = mPipeSink->availableToWrite();

                const size_t pipeFrames = monoPipe->maxFrames();

                const size_t framesLeft = pipeFrames - max(availableToWrite, 0);

                // HAL_framecount <= framesDelay ~ framesLeft / 2 <= Normal_Mixer_framecount

                const size_t framesDelay = std::min(

                        mNormalFrameCount, max(framesLeft / 2, mFrameCount));

                ALOGV("pipeFrames:%zu framesLeft:%zu framesDelay:%zu",

                        pipeFrames, framesLeft, framesDelay);

                mSleepTimeUs = framesDelay * MICROS_PER_SECOND / mSampleRate;

            } else {

                mSleepTimeUs = mActiveSleepTimeUs >> sleepTimeShift;

                if (mSleepTimeUs < kMinThreadSleepTimeUs) {

                    mSleepTimeUs = kMinThreadSleepTimeUs;

                if (sleepTimeShift < kMaxThreadSleepTimeShift) {

                    sleepTimeShift++;

                }

            }

        } else {

            mSleepTimeUs = mIdleSleepTimeUs;

        }