1 files changed, 0 insertions, 112 deletions
diff --git a/externals/oboe/src/common/StabilizedCallback.cpp b/externals/oboe/src/common/StabilizedCallback.cpp
deleted file mode 100644
index 0c561a53fc..0000000000
--- a/externals/oboe/src/common/StabilizedCallback.cpp
+++ /dev/null
@@ -1,112 +0,0 @@
-/*
- * Copyright (C) 2018 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "common/Trace.h"
-#include "oboe/AudioClock.h"
-#include "oboe/StabilizedCallback.h"
-
-constexpr int32_t kLoadGenerationStepSizeNanos = 20000;
-constexpr float kPercentageOfCallbackToUse = 0.8;
-
-using namespace oboe;
-
-StabilizedCallback::StabilizedCallback(AudioStreamCallback *callback) : mCallback(callback){
-    Trace::initialize();
-}
-
-/**
- * An audio callback which attempts to do work for a fixed amount of time.
- *
- * @param oboeStream
- * @param audioData
- * @param numFrames
- * @return
- */
-DataCallbackResult
-StabilizedCallback::onAudioReady(AudioStream *oboeStream, void *audioData, int32_t numFrames) {
-
-    int64_t startTimeNanos = AudioClock::getNanoseconds();
-
-    if (mFrameCount == 0){
-        mEpochTimeNanos = startTimeNanos;
-    }
-
-    int64_t durationSinceEpochNanos = startTimeNanos - mEpochTimeNanos;
-
-    // In an ideal world the callback start time will be exactly the same as the duration of the
-    // frames already read/written into the stream. In reality the callback can start early
-    // or late. By finding the delta we can calculate the target duration for our stabilized
-    // callback.
-    int64_t idealStartTimeNanos = (mFrameCount * kNanosPerSecond) / oboeStream->getSampleRate();
-    int64_t lateStartNanos = durationSinceEpochNanos - idealStartTimeNanos;
-
-    if (lateStartNanos < 0){
-        // This was an early start which indicates that our previous epoch was a late callback.
-        // Update our epoch to this more accurate time.
-        mEpochTimeNanos = startTimeNanos;
-        mFrameCount = 0;
-    }
-
-    int64_t numFramesAsNanos = (numFrames * kNanosPerSecond) / oboeStream->getSampleRate();
-    int64_t targetDurationNanos = static_cast<int64_t>(
-            (numFramesAsNanos * kPercentageOfCallbackToUse) - lateStartNanos);
-
-    Trace::beginSection("Actual load");
-    DataCallbackResult result = mCallback->onAudioReady(oboeStream, audioData, numFrames);
-    Trace::endSection();
-
-    int64_t executionDurationNanos = AudioClock::getNanoseconds() - startTimeNanos;
-    int64_t stabilizingLoadDurationNanos = targetDurationNanos - executionDurationNanos;
-
-    Trace::beginSection("Stabilized load for %lldns", stabilizingLoadDurationNanos);
-    generateLoad(stabilizingLoadDurationNanos);
-    Trace::endSection();
-
-    // Wraparound: At 48000 frames per second mFrameCount wraparound will occur after 6m years,
-    // significantly longer than the average lifetime of an Android phone.
-    mFrameCount += numFrames;
-    return result;
-}
-
-void StabilizedCallback::generateLoad(int64_t durationNanos) {
-
-    int64_t currentTimeNanos = AudioClock::getNanoseconds();
-    int64_t deadlineTimeNanos = currentTimeNanos + durationNanos;
-
-    // opsPerStep gives us an estimated number of operations which need to be run to fully utilize
-    // the CPU for a fixed amount of time (specified by kLoadGenerationStepSizeNanos).
-    // After each step the opsPerStep value is re-calculated based on the actual time taken to
-    // execute those operations.
-    auto opsPerStep = (int)(mOpsPerNano * kLoadGenerationStepSizeNanos);
-    int64_t stepDurationNanos = 0;
-    int64_t previousTimeNanos = 0;
-
-    while (currentTimeNanos <= deadlineTimeNanos){
-
-        for (int i = 0; i < opsPerStep; i++) cpu_relax();
-
-        previousTimeNanos = currentTimeNanos;
-        currentTimeNanos = AudioClock::getNanoseconds();
-        stepDurationNanos = currentTimeNanos - previousTimeNanos;
-
-        // Calculate exponential moving average to smooth out values, this acts as a low pass filter.
-        // @see https://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average
-        static const float kFilterCoefficient = 0.1;
-        auto measuredOpsPerNano = (double) opsPerStep / stepDurationNanos;
-        mOpsPerNano = kFilterCoefficient * measuredOpsPerNano + (1.0 - kFilterCoefficient) * mOpsPerNano;
-        opsPerStep = (int) (mOpsPerNano * kLoadGenerationStepSizeNanos);
-    }
-}