aaudio: add thread safety annotation

Also improve naming to clarify lock requirements.

And call some locked methods that were not called before.
Although they were protected with a different lock so
it should have no effect.

Bug: 171296283
Test: adb logcat *:F
Test: In another window:
Test: atest AAudioTestCases
Change-Id: I6e863cbdea9250188e3f4b8f8654ef71c8951e74
diff --git a/media/libaaudio/src/client/AudioStreamInternal.cpp b/media/libaaudio/src/client/AudioStreamInternal.cpp
index c2dcd35..809c76e 100644
--- a/media/libaaudio/src/client/AudioStreamInternal.cpp
+++ b/media/libaaudio/src/client/AudioStreamInternal.cpp
@@ -418,7 +418,6 @@
     }
 }
 
-// This must be called under mStreamLock.
 aaudio_result_t AudioStreamInternal::requestStop_l() {
     aaudio_result_t result = stopCallback_l();
     if (result != AAUDIO_OK) {
@@ -428,7 +427,7 @@
     // The stream may have been unlocked temporarily to let a callback finish
     // and the callback may have stopped the stream.
     // Check to make sure the stream still needs to be stopped.
-    // See also AudioStream::safeStop().
+    // See also AudioStream::safeStop_l().
     if (!(isActive() || getState() == AAUDIO_STREAM_STATE_DISCONNECTED)) {
         ALOGD("%s() returning early, not active or disconnected", __func__);
         return AAUDIO_OK;
@@ -810,15 +809,6 @@
     return mBufferCapacityInFrames;
 }
 
-aaudio_result_t AudioStreamInternal::joinThread(void** returnArg) {
-    return AudioStream::joinThread(returnArg, calculateReasonableTimeout(getFramesPerBurst()));
-}
-
-// This must be called under mStreamLock.
-aaudio_result_t AudioStreamInternal::joinThread_l(void** returnArg) {
-    return AudioStream::joinThread_l(returnArg, calculateReasonableTimeout(getFramesPerBurst()));
-}
-
 bool AudioStreamInternal::isClockModelInControl() const {
     return isActive() && mAudioEndpoint->isFreeRunning() && mClockModel.isRunning();
 }
diff --git a/media/libaaudio/src/client/AudioStreamInternal.h b/media/libaaudio/src/client/AudioStreamInternal.h
index 1838b53..fbe4c13 100644
--- a/media/libaaudio/src/client/AudioStreamInternal.h
+++ b/media/libaaudio/src/client/AudioStreamInternal.h
@@ -44,10 +44,6 @@
     AudioStreamInternal(AAudioServiceInterface  &serviceInterface, bool inService);
     virtual ~AudioStreamInternal();
 
-    aaudio_result_t requestStart_l() override;
-
-    aaudio_result_t requestStop_l() override;
-
     aaudio_result_t getTimestamp(clockid_t clockId,
                                        int64_t *framePosition,
                                        int64_t *timeNanoseconds) override;
@@ -56,8 +52,6 @@
 
     aaudio_result_t open(const AudioStreamBuilder &builder) override;
 
-    aaudio_result_t release_l() override;
-
     aaudio_result_t setBufferSize(int32_t requestedFrames) override;
 
     int32_t getBufferSize() const override;
@@ -72,12 +66,9 @@
 
     aaudio_result_t unregisterThread() override;
 
-    aaudio_result_t joinThread(void** returnArg);
-
     // Called internally from 'C'
     virtual void *callbackLoop() = 0;
 
-
     bool isMMap() override {
         return true;
     }
@@ -96,6 +87,10 @@
     }
 
 protected:
+    aaudio_result_t requestStart_l() REQUIRES(mStreamLock) override;
+    aaudio_result_t requestStop_l() REQUIRES(mStreamLock) override;
+
+    aaudio_result_t release_l() REQUIRES(mStreamLock) override;
 
     aaudio_result_t processData(void *buffer,
                          int32_t numFrames,
@@ -119,8 +114,6 @@
 
     aaudio_result_t stopCallback_l();
 
-    aaudio_result_t joinThread_l(void** returnArg);
-
     virtual void prepareBuffersForStart() {}
 
     virtual void advanceClientToMatchServerPosition(int32_t serverMargin = 0) = 0;