1 files changed, 59 insertions, 1 deletions

diff --git a/libs/gui/BufferQueueCore.cpp b/libs/gui/BufferQueueCore.cpp
index edebc45..29415c9 100644
--- a/libs/gui/BufferQueueCore.cpp
+++ b/libs/gui/BufferQueueCore.cpp
@@ -53,6 +53,8 @@ BufferQueueCore::BufferQueueCore(const sp<IGraphicBufferAlloc>& allocator) :
     mConnectedProducerListener(),
     mSlots(),
     mQueue(),
+    mFreeSlots(),
+    mFreeBuffers(),
     mOverrideMaxBufferCount(0),
     mDequeueCondition(),
     mUseAsyncBuffer(true),
@@ -76,6 +78,9 @@ BufferQueueCore::BufferQueueCore(const sp<IGraphicBufferAlloc>& allocator) :
             BQ_LOGE("createGraphicBufferAlloc failed");
         }
     }
+    for (int slot = 0; slot < BufferQueueDefs::NUM_BUFFER_SLOTS; ++slot) {
+        mFreeSlots.insert(slot);
+    }
 }
 
 BufferQueueCore::~BufferQueueCore() {}
@@ -190,12 +195,20 @@ status_t BufferQueueCore::setDefaultMaxBufferCountLocked(int count) {
 
 void BufferQueueCore::freeBufferLocked(int slot) {
     BQ_LOGV("freeBufferLocked: slot %d", slot);
+    bool hadBuffer = mSlots[slot].mGraphicBuffer != NULL;
     mSlots[slot].mGraphicBuffer.clear();
     if (mSlots[slot].mBufferState == BufferSlot::ACQUIRED) {
         mSlots[slot].mNeedsCleanupOnRelease = true;
     }
+    if (mSlots[slot].mBufferState != BufferSlot::FREE) {
+        mFreeSlots.insert(slot);
+    } else if (hadBuffer) {
+        // If the slot was FREE, but we had a buffer, we need to move this slot
+        // from the free buffers list to the the free slots list
+        mFreeBuffers.remove(slot);
+        mFreeSlots.insert(slot);
+    }
     mSlots[slot].mBufferState = BufferSlot::FREE;
-    mSlots[slot].mFrameNumber = UINT32_MAX;
     mSlots[slot].mAcquireCalled = false;
 
     // Destroy fence as BufferQueue now takes ownership
@@ -204,6 +217,7 @@ void BufferQueueCore::freeBufferLocked(int slot) {
         mSlots[slot].mEglFence = EGL_NO_SYNC_KHR;
     }
     mSlots[slot].mFence = Fence::NO_FENCE;
+    validateConsistencyLocked();
 }
 
 void BufferQueueCore::freeAllBuffersLocked() {
@@ -236,4 +250,48 @@ void BufferQueueCore::waitWhileAllocatingLocked() const {
     }
 }
 
+void BufferQueueCore::validateConsistencyLocked() const {
+    static const useconds_t PAUSE_TIME = 0;
+    for (int slot = 0; slot < BufferQueueDefs::NUM_BUFFER_SLOTS; ++slot) {
+        bool isInFreeSlots = mFreeSlots.count(slot) != 0;
+        bool isInFreeBuffers =
+                std::find(mFreeBuffers.cbegin(), mFreeBuffers.cend(), slot) !=
+                mFreeBuffers.cend();
+        if (mSlots[slot].mBufferState == BufferSlot::FREE) {
+            if (mSlots[slot].mGraphicBuffer == NULL) {
+                if (!isInFreeSlots) {
+                    BQ_LOGE("Slot %d is FREE but is not in mFreeSlots", slot);
+                    usleep(PAUSE_TIME);
+                }
+                if (isInFreeBuffers) {
+                    BQ_LOGE("Slot %d is in mFreeSlots "
+                            "but is also in mFreeBuffers", slot);
+                    usleep(PAUSE_TIME);
+                }
+            } else {
+                if (!isInFreeBuffers) {
+                    BQ_LOGE("Slot %d is FREE but is not in mFreeBuffers", slot);
+                    usleep(PAUSE_TIME);
+                }
+                if (isInFreeSlots) {
+                    BQ_LOGE("Slot %d is in mFreeBuffers "
+                            "but is also in mFreeSlots", slot);
+                    usleep(PAUSE_TIME);
+                }
+            }
+        } else {
+            if (isInFreeSlots) {
+                BQ_LOGE("Slot %d is in mFreeSlots but is not FREE (%d)",
+                        slot, mSlots[slot].mBufferState);
+                usleep(PAUSE_TIME);
+            }
+            if (isInFreeBuffers) {
+                BQ_LOGE("Slot %d is in mFreeBuffers but is not FREE (%d)",
+                        slot, mSlots[slot].mBufferState);
+                usleep(PAUSE_TIME);
+            }
+        }
+    }
+}
+
 } // namespace android