OboeTester: Cold Start Latency should wait for valid timestamps (#2276)

Author: robertwu1

apps/OboeTester/app/src/main/cpp/TestColdStartLatency.cpp

@@ -96,6 +96,12 @@ int32_t TestColdStartLatency::getColdStartTimeMicros() {
     return coldStartLatencyNanos / NANOS_PER_MICROSECOND;
 }
 
+void TestColdStartLatency::waitForValidTimestamp() {
+    while (!mStream->getTimestamp(CLOCK_MONOTONIC)) {
+        usleep(kPollPeriodMillis * 1000);
+    }
+}
+
 // Callback that sleeps then touches the audio buffer.
 DataCallbackResult TestColdStartLatency::MyDataCallback::onAudioReady(
         AudioStream *audioStream,

apps/OboeTester/app/src/main/cpp/TestColdStartLatency.h

@@ -30,6 +30,8 @@ class TestColdStartLatency {
     int32_t start();
     int32_t close();
 
+    void waitForValidTimestamp();
+
     int32_t getColdStartTimeMicros();
 
     int32_t getOpenTimeMicros() {
@@ -71,6 +73,7 @@ class TestColdStartLatency {
     std::shared_ptr<MyDataCallback> mDataCallback;
 
     static constexpr int kChannelCount = 1;
+    static constexpr int kPollPeriodMillis = 1;
 };
 
 #endif //OBOETESTER_TEST_COLD_START_LATENCY_H

apps/OboeTester/app/src/main/cpp/jni-bridge.cpp

@@ -1082,6 +1082,12 @@ Java_com_mobileer_oboetester_TestColdStartLatencyActivity_getColdStartTimeMicros
     return sColdStartLatency.getColdStartTimeMicros();
 }
 
+JNIEXPORT void JNICALL
+Java_com_mobileer_oboetester_TestColdStartLatencyActivity_waitForValidTimestamp(
+        JNIEnv *env, jobject instance) {
+    sColdStartLatency.waitForValidTimestamp();
+}
+
 JNIEXPORT jint JNICALL
 Java_com_mobileer_oboetester_TestColdStartLatencyActivity_getAudioDeviceId(
         JNIEnv *env, jobject instance) {

apps/OboeTester/app/src/main/java/com/mobileer/oboetester/TestColdStartLatencyActivity.java

@@ -140,6 +140,7 @@ public void run() {
                     startStream();
                     log("requestStart() Latency: " + getStartTimeMicros() / 1000 + " msec");
                     sleep(startSleepTimeMillis);
+                    waitForValidTimestamp();
                     log("Cold Start Latency: " + getColdStartTimeMicros() / 1000 + " msec");
                     closeStream();
                 } catch (InterruptedException e) {
@@ -181,6 +182,7 @@ private native int openStream(boolean useInput, boolean useLowLatency, boolean u
                                   boolean useExclusive);
     private native int startStream();
     private native int closeStream();
+    private native void waitForValidTimestamp();
     private native int getOpenTimeMicros();
     private native int getStartTimeMicros();
     private native int getColdStartTimeMicros();