commit b0abafbf0a6174e8c8933cc5fb19501a2d22c53b
author Mikhail Naganov <mnaganov@google.com> Tue Jan 31 17:24:48 2017 -0800
committer Mikhail Naganov <mnaganov@google.com> Thu Feb 02 17:00:42 2017 -0800
tree d119b77826ef8b5b1190886dab505360c86f4f2e
parent bbd6adda5af693692c889b47ef1394a578c5baea

audiohal: Make closing of effects and streams fast

There were two problems:

1. Joining of reader / writer / process threads (the threads that
   interact with HAL) was taking up to 1 second because the thread
   was usually waiting for an event flag to be toggled, or a 1s
   timeout.

2. Calling IStream.close or IEffect.close shouldn't tax the caller.
   Changed the code so a call to close only signals the thread that
   it's time to exit, and then the thread is only joined in the
   effect or stream destructor.

Bug: 34800063
Bug: 34499806
Test: see repro steps in the bugs
Change-Id: Ife20524a1eba4ec9a78152e89862526e8cd5c960

audio/effect/2.0/default/Effect.cpp

diff --git a/audio/effect/2.0/default/Effect.cpp b/audio/effect/2.0/default/Effect.cpp
index 3c97fc4..0a4aeb7 100644
--- a/audio/effect/2.0/default/Effect.cpp
+++ b/audio/effect/2.0/default/Effect.cpp
@@ -17,8 +17,11 @@
 #include <memory.h>
 
 #define LOG_TAG "EffectHAL"
+#define ATRACE_TAG ATRACE_TAG_AUDIO
+
 #include <android/log.h>
 #include <media/EffectsFactoryApi.h>
+#include <utils/Trace.h>
 
 #include "Conversions.h"
 #include "Effect.h"
@@ -78,8 +81,9 @@
                 static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_PROCESS_ALL),
                 &efState,
                 NS_PER_SEC);
-        if (!(efState & static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_PROCESS_ALL))) {
-            continue;  // Nothing to do.
+        if (!(efState & static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_PROCESS_ALL))
+                || (efState & static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_QUIT))) {
+            continue;  // Nothing to do or time to quit.
         }
         Result retval = Result::OK;
         if (efState & static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_PROCESS_REVERSE)
@@ -134,7 +138,23 @@
 }
 
 Effect::~Effect() {
+    ATRACE_CALL();
     close();
+    if (mProcessThread.get()) {
+        ATRACE_NAME("mProcessThread->join");
+        status_t status = mProcessThread->join();
+        ALOGE_IF(status, "processing thread exit error: %s", strerror(-status));
+    }
+    if (mEfGroup) {
+        status_t status = EventFlag::deleteEventFlag(&mEfGroup);
+        ALOGE_IF(status, "processing MQ event flag deletion error: %s", strerror(-status));
+    }
+    mInBuffer.clear();
+    mOutBuffer.clear();
+    int status = EffectRelease(mHandle);
+    ALOGW_IF(status, "Error releasing effect %p: %s", mHandle, strerror(-status));
+    EffectMap::getInstance().remove(mHandle);
+    mHandle = 0;
 }
 
 // static
@@ -731,19 +751,10 @@
     mIsClosed = true;
     if (mProcessThread.get()) {
         mStopProcessThread.store(true, std::memory_order_release);
-        status_t status = mProcessThread->requestExitAndWait();
-        ALOGE_IF(status, "processing thread exit error: %s", strerror(-status));
     }
     if (mEfGroup) {
-        status_t status = EventFlag::deleteEventFlag(&mEfGroup);
-        ALOGE_IF(status, "processing MQ event flag deletion error: %s", strerror(-status));
+        mEfGroup->wake(static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_QUIT));
     }
-    mInBuffer.clear();
-    mOutBuffer.clear();
-    int status = EffectRelease(mHandle);
-    ALOGW_IF(status, "Error releasing effect %p: %s", mHandle, strerror(-status));
-    EffectMap::getInstance().remove(mHandle);
-    mHandle = 0;
     return Result::OK;
 }