From cba287b9716155183faf21865a6c28ba49ffe486 Mon Sep 17 00:00:00 2001
From: John Reck <jreck@google.com>
Date: Tue, 10 Nov 2015 12:52:44 -0800
Subject: [PATCH] Fix threading issues

Bug: 25584167
Change-Id: I413ef9e0c86f7cca1f7d085e0071745ca0192853
---
 libs/hwui/renderthread/RenderProxy.cpp  |  5 ++++-
 libs/hwui/renderthread/RenderProxy.h    |  3 +++
 libs/hwui/renderthread/RenderThread.cpp | 14 +++++++++++---
 libs/hwui/renderthread/RenderThread.h   |  4 ----
 4 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/libs/hwui/renderthread/RenderProxy.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index a1107f029691c..15ccd6ac5b6bc 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -563,7 +563,10 @@ void RenderProxy::post(RenderTask* task) {
 void* RenderProxy::postAndWait(MethodInvokeRenderTask* task) {
     void* retval;
     task->setReturnPtr(&retval);
-    mRenderThread.queueAndWait(task);
+    SignalingRenderTask syncTask(task, &mSyncMutex, &mSyncCondition);
+    AutoMutex _lock(mSyncMutex);
+    mRenderThread.queue(&syncTask);
+    mSyncCondition.wait(mSyncMutex);
     return retval;
 }
 
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index d0e601e09be68..338fab650876c 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -117,6 +117,9 @@ private:
 
     DrawFrameTask mDrawFrameTask;
 
+    Mutex mSyncMutex;
+    Condition mSyncCondition;
+
     void destroyContext();
 
     void post(RenderTask* task);
diff --git a/libs/hwui/renderthread/RenderThread.cpp b/libs/hwui/renderthread/RenderThread.cpp
index 526a84861d98b..9fb30c928c005 100644
--- a/libs/hwui/renderthread/RenderThread.cpp
+++ b/libs/hwui/renderthread/RenderThread.cpp
@@ -25,7 +25,9 @@
 #include <gui/ISurfaceComposer.h>
 #include <gui/SurfaceComposerClient.h>
 #include <sys/resource.h>
+#include <utils/Condition.h>
 #include <utils/Log.h>
+#include <utils/Mutex.h>
 
 namespace android {
 namespace uirenderer {
@@ -325,10 +327,16 @@ void RenderThread::queue(RenderTask* task) {
 }
 
 void RenderThread::queueAndWait(RenderTask* task) {
-    SignalingRenderTask syncTask(task, &mSyncMutex, &mSyncCondition);
-    AutoMutex _lock(mSyncMutex);
+    // These need to be local to the thread to avoid the Condition
+    // signaling the wrong thread. The easiest way to achieve that is to just
+    // make this on the stack, although that has a slight cost to it
+    Mutex mutex;
+    Condition condition;
+    SignalingRenderTask syncTask(task, &mutex, &condition);
+
+    AutoMutex _lock(mutex);
     queue(&syncTask);
-    mSyncCondition.wait(mSyncMutex);
+    condition.wait(mutex);
 }
 
 void RenderThread::queueAtFront(RenderTask* task) {
diff --git a/libs/hwui/renderthread/RenderThread.h b/libs/hwui/renderthread/RenderThread.h
index d8c7e61f34eb0..076e3d43a2c9b 100644
--- a/libs/hwui/renderthread/RenderThread.h
+++ b/libs/hwui/renderthread/RenderThread.h
@@ -27,9 +27,7 @@
 #include <utils/Looper.h>
 #include <utils/Thread.h>
 
-#include <condition_variable>
 #include <memory>
-#include <mutex>
 #include <set>
 
 namespace android {
@@ -127,8 +125,6 @@ private:
 
     nsecs_t mNextWakeup;
     TaskQueue mQueue;
-    Mutex mSyncMutex;
-    Condition mSyncCondition;
 
     DisplayInfo mDisplayInfo;