commit eae5c56fb402c112e643a3c5590a6ce3a4c41fe7
author Shunkai Yao <yaoshunkai@google.com> Thu Mar 09 02:24:00 2023 +0000
committer Shunkai Yao <yaoshunkai@google.com> Thu Mar 09 02:30:15 2023 +0000
tree eb044a2de5436683054079c9afa98efd13bd21e3
parent b862e6e20b63726dfeb8dc327932b8e475726233

Add sleep in EffectThread to avoid busy wait

Bug: 261129656
Test: Enable AIDL and run YTM on pixel phone
Change-Id: If7ea5324b8a884e8f07b6855b70cb33b4c7868e4

audio/aidl/default/EffectThread.cpp

diff --git a/audio/aidl/default/EffectThread.cpp b/audio/aidl/default/EffectThread.cpp
index 024c0ea..4f8fb3c 100644
--- a/audio/aidl/default/EffectThread.cpp
+++ b/audio/aidl/default/EffectThread.cpp
@@ -34,13 +34,14 @@
 };
 
 RetCode EffectThread::createThread(std::shared_ptr<EffectContext> context, const std::string& name,
-                                   const int priority) {
+                                   int priority, int sleepUs /* kSleepTimeUs */) {
     if (mThread.joinable()) {
         LOG(WARNING) << __func__ << " thread already created, no-op";
         return RetCode::SUCCESS;
     }
     mName = name;
     mPriority = priority;
+    mSleepTimeUs = sleepUs;
     {
         std::lock_guard lg(mThreadMutex);
         mThreadContext = std::move(context);
@@ -134,7 +135,7 @@
         LOG(DEBUG) << __func__ << " done processing, effect consumed " << status.fmqConsumed
                    << " produced " << status.fmqProduced;
     } else {
-        // TODO: maybe add some sleep here to avoid busy waiting
+        usleep(mSleepTimeUs);
     }
 }
 

audio/aidl/default/include/effect-impl/EffectThread.h

diff --git a/audio/aidl/default/include/effect-impl/EffectThread.h b/audio/aidl/default/include/effect-impl/EffectThread.h
index 9b1a75b..f9c6a31 100644
--- a/audio/aidl/default/include/effect-impl/EffectThread.h
+++ b/audio/aidl/default/include/effect-impl/EffectThread.h
@@ -35,7 +35,7 @@
 
     // called by effect implementation.
     RetCode createThread(std::shared_ptr<EffectContext> context, const std::string& name,
-                         const int priority = ANDROID_PRIORITY_URGENT_AUDIO);
+                         int priority = ANDROID_PRIORITY_URGENT_AUDIO, int sleepUs = kSleepTimeUs);
     RetCode destroyThread();
     RetCode startThread();
     RetCode stopThread();
@@ -72,7 +72,8 @@
     virtual void process_l() REQUIRES(mThreadMutex);
 
   private:
-    const int kMaxTaskNameLen = 15;
+    static constexpr int kMaxTaskNameLen = 15;
+    static constexpr int kSleepTimeUs = 2000;  // in micro-second
     std::mutex mThreadMutex;
     std::condition_variable mCv;
     bool mExit GUARDED_BY(mThreadMutex) = false;
@@ -80,6 +81,7 @@
     std::shared_ptr<EffectContext> mThreadContext GUARDED_BY(mThreadMutex);
     std::thread mThread;
     int mPriority;
+    int mSleepTimeUs = kSleepTimeUs;  // sleep time in micro-second
     std::string mName;
 
     RetCode handleStartStop(bool stop);