commit daa60c22d6666980ef563aeac454dd32b9034f8f
author Andy Hung <hunga@google.com> Mon Mar 15 19:01:51 2021 -0700
committer Andy Hung <hunga@google.com> Wed Mar 17 10:45:07 2021 -0700
tree 1bdae63fcce9f39d969f3089da2a33df7a511ba7
parent c4b72cd7efb0ea7a5454c80b2e303ccb8ebba053

SoundPool: Avoid busy waiting during stream restart

A stream on the restart queue can cause the StreamManager to
busy-wait.  This was introduced by a fix
commit ba04dbe7732bc2d016bf81c81bd349d931de63f2.

Test: Verbose log on StreamManager.cpp, run SoundPool CTS tests.
Bug: 182923919
Merged-In: Iae794bc957869426a4e1e27cd3c088aa9dd83208
Change-Id: Iae794bc957869426a4e1e27cd3c088aa9dd83208

media/jni/soundpool/StreamManager.cpp

diff --git a/media/jni/soundpool/StreamManager.cpp b/media/jni/soundpool/StreamManager.cpp
index 49c2b39..309d71c 100644
--- a/media/jni/soundpool/StreamManager.cpp
+++ b/media/jni/soundpool/StreamManager.cpp
@@ -358,14 +358,14 @@
 void StreamManager::run(int32_t id)
 {
     ALOGV("%s(%d) entering", __func__, id);
-    int64_t waitTimeNs = kWaitTimeBeforeCloseNs;
+    int64_t waitTimeNs = 0;  // on thread start, mRestartStreams can be non-empty.
     std::unique_lock lock(mStreamManagerLock);
     while (!mQuit) {
-        if (mRestartStreams.empty()) { // on thread start, mRestartStreams can be non-empty.
+        if (waitTimeNs > 0) {
             mStreamManagerCondition.wait_for(
                     lock, std::chrono::duration<int64_t, std::nano>(waitTimeNs));
         }
-        ALOGV("%s(%d) awake", __func__, id);
+        ALOGV("%s(%d) awake lock waitTimeNs:%lld", __func__, id, (long long)waitTimeNs);
 
         sanityCheckQueue_l();