commit 83729883eecd31a9907bc79bc21998a90f17105c
author Ady Abraham <adyabr@google.com> Fri Dec 07 12:26:48 2018 -0800
committer Ady Abraham <adyabr@google.com> Wed Dec 12 11:26:51 2018 -0800
tree c1aca6e748ad8418883b758125bc56b85e52a19f
parent 227d1b1098a8d4fa562ca23914c7472c337acf26

SurfaceFlinger: protect state members in Layer

Add proper locking to protect state members in Layer.
These members are accessed by both the main thread and binder.

Bug: 119481871
Test: SurfaceFlinger unit tests
Test: go/wm-smoke
Change-Id: I12d47711992e09c0677b77f7e1b36c1254b63a1b

services/surfaceflinger/BufferQueueLayer.cpp

diff --git a/services/surfaceflinger/BufferQueueLayer.cpp b/services/surfaceflinger/BufferQueueLayer.cpp
index b784d11..70d52f1 100644
--- a/services/surfaceflinger/BufferQueueLayer.cpp
+++ b/services/surfaceflinger/BufferQueueLayer.cpp
@@ -51,7 +51,7 @@
     return history;
 }
 
-bool BufferQueueLayer::getTransformToDisplayInverse() const {
+bool BufferQueueLayer::getTransformToDisplayInverseLocked() const {
     return mConsumer->getTransformToDisplayInverse();
 }
 
@@ -131,7 +131,7 @@
     return mConsumer->getTimestamp();
 }
 
-std::shared_ptr<FenceTime> BufferQueueLayer::getCurrentFenceTime() const {
+std::shared_ptr<FenceTime> BufferQueueLayer::getCurrentFenceTimeLocked() const {
     return mConsumer->getCurrentFenceTime();
 }
 
@@ -192,6 +192,7 @@
 
 std::optional<Region> BufferQueueLayer::latchSidebandStream(bool& recomputeVisibleRegions) {
     bool sidebandStreamChanged = true;
+    Mutex::Autolock lock(mStateMutex);
     if (mSidebandStreamChanged.compare_exchange_strong(sidebandStreamChanged, false)) {
         // mSidebandStreamChanged was changed to false
         // replicated in LayerBE until FE/BE is ready to be synchronized
@@ -200,15 +201,15 @@
             setTransactionFlags(eTransactionNeeded);
             mFlinger->setTransactionFlags(eTraversalNeeded);
         }
-        recomputeVisibleRegions = true;
 
+        recomputeVisibleRegions = true;
         const State& s(getDrawingState());
-        return getTransform().transform(Region(Rect(s.active_legacy.w, s.active_legacy.h)));
+        return getTransformLocked().transform(Region(Rect(s.active_legacy.w, s.active_legacy.h)));
     }
     return {};
 }
 
-bool BufferQueueLayer::hasFrameUpdate() const {
+bool BufferQueueLayer::hasFrameUpdateLocked() const {
     return mQueuedFrames > 0;
 }
 
@@ -228,16 +229,18 @@
     // buffer mode.
     bool queuedBuffer = false;
     const int32_t layerID = getSequence();
-    LayerRejecter r(mDrawingState, getCurrentState(), recomputeVisibleRegions,
+    status_t updateResult;
+    LayerRejecter r(mState.drawing, getCurrentState(), recomputeVisibleRegions,
                     getProducerStickyTransform() != 0, mName.string(), mOverrideScalingMode,
-                    getTransformToDisplayInverse(), mFreezeGeometryUpdates);
+                    getTransformToDisplayInverseLocked(), mFreezeGeometryUpdates);
 
     const nsecs_t expectedPresentTime = mFlinger->mUseScheduler
             ? mFlinger->mScheduler->mPrimaryDispSync->expectedPresentTime()
             : mFlinger->mPrimaryDispSync->expectedPresentTime();
-    status_t updateResult =
-            mConsumer->updateTexImage(&r, expectedPresentTime, &mAutoRefresh, &queuedBuffer,
-                                      mLastFrameNumberReceived, releaseFence);
+
+    updateResult = mConsumer->updateTexImage(&r, expectedPresentTime, &mAutoRefresh, &queuedBuffer,
+                                             mLastFrameNumberReceived, releaseFence);
+
     if (updateResult == BufferQueue::PRESENT_LATER) {
         // Producer doesn't want buffer to be displayed yet.  Signal a
         // layer update so we check again at the next opportunity.