commit 638f45b72ba2201ab66addc5e15f3f2d0bd7f8d1
author Andy Hung <hunga@google.com> Mon Jan 18 20:02:56 2021 -0800
committer Andy Hung <hunga@google.com> Tue Jan 19 10:14:49 2021 -0800
tree dc2ca1b340a361303617db5dbe88a07183c06370
parent b3bd0a0713d6ca192dce7be6ebfb4deb07648150

StreamHalHidl: Use atomic_wp and make pointers const

Avoid concurrency issues with modification of wp.

Test: basic audio
Bug: 177278988
Change-Id: I5b968a1dad24e1d6c18260884d35c3170661da01

media/libaudiohal/impl/StreamHalHidl.cpp

diff --git a/media/libaudiohal/impl/StreamHalHidl.cpp b/media/libaudiohal/impl/StreamHalHidl.cpp
index 09a7c1c..3f9bccb 100644
--- a/media/libaudiohal/impl/StreamHalHidl.cpp
+++ b/media/libaudiohal/impl/StreamHalHidl.cpp
@@ -61,10 +61,6 @@
     }
 }
 
-StreamHalHidl::~StreamHalHidl() {
-    mStream = nullptr;
-}
-
 status_t StreamHalHidl::getSampleRate(uint32_t *rate) {
     if (!mStream) return NO_INIT;
     return processReturn("getSampleRate", mStream->getSampleRate(), rate);
@@ -286,7 +282,7 @@
     }
 
   private:
-    wp<StreamOutHalHidl> mStream;
+    const wp<StreamOutHalHidl> mStream;
 };
 
 }  // namespace
@@ -297,21 +293,19 @@
 
 StreamOutHalHidl::~StreamOutHalHidl() {
     if (mStream != 0) {
-        if (mCallback.unsafe_get()) {
+        if (mCallback.load().unsafe_get()) {
             processReturn("clearCallback", mStream->clearCallback());
         }
 #if MAJOR_VERSION >= 6
-        if (mEventCallback.unsafe_get() != nullptr) {
+        if (mEventCallback.load().unsafe_get() != nullptr) {
             processReturn("setEventCallback",
                     mStream->setEventCallback(nullptr));
         }
 #endif
         processReturn("close", mStream->close());
-        mStream.clear();
     }
-    mCallback.clear();
-    mEventCallback.clear();
-    hardware::IPCThreadState::self()->flushCommands();
+    mCallback = nullptr;
+    mEventCallback = nullptr;
     if (mEfGroup) {
         EventFlag::deleteEventFlag(&mEfGroup);
     }
@@ -364,7 +358,7 @@
 
     if (bytes == 0 && !mDataMQ) {
         // Can't determine the size for the MQ buffer. Wait for a non-empty write request.
-        ALOGW_IF(mCallback.unsafe_get(), "First call to async write with 0 bytes");
+        ALOGW_IF(mCallback.load().unsafe_get(), "First call to async write with 0 bytes");
         return OK;
     }
 
@@ -680,28 +674,28 @@
 #endif
 
 void StreamOutHalHidl::onWriteReady() {
-    sp<StreamOutHalInterfaceCallback> callback = mCallback.promote();
+    sp<StreamOutHalInterfaceCallback> callback = mCallback.load().promote();
     if (callback == 0) return;
     ALOGV("asyncCallback onWriteReady");
     callback->onWriteReady();
 }
 
 void StreamOutHalHidl::onDrainReady() {
-    sp<StreamOutHalInterfaceCallback> callback = mCallback.promote();
+    sp<StreamOutHalInterfaceCallback> callback = mCallback.load().promote();
     if (callback == 0) return;
     ALOGV("asyncCallback onDrainReady");
     callback->onDrainReady();
 }
 
 void StreamOutHalHidl::onError() {
-    sp<StreamOutHalInterfaceCallback> callback = mCallback.promote();
+    sp<StreamOutHalInterfaceCallback> callback = mCallback.load().promote();
     if (callback == 0) return;
     ALOGV("asyncCallback onError");
     callback->onError();
 }
 
 void StreamOutHalHidl::onCodecFormatChanged(const std::basic_string<uint8_t>& metadataBs) {
-    sp<StreamOutHalInterfaceEventCallback> callback = mEventCallback.promote();
+    sp<StreamOutHalInterfaceEventCallback> callback = mEventCallback.load().promote();
     if (callback == nullptr) return;
     ALOGV("asyncCodecFormatCallback %s", __func__);
     callback->onCodecFormatChanged(metadataBs);
@@ -715,8 +709,6 @@
 StreamInHalHidl::~StreamInHalHidl() {
     if (mStream != 0) {
         processReturn("close", mStream->close());
-        mStream.clear();
-        hardware::IPCThreadState::self()->flushCommands();
     }
     if (mEfGroup) {
         EventFlag::deleteEventFlag(&mEfGroup);