commit 9e3cb55b8f6f007906872decfe3b8a2541e94dd2
author Lajos Molnar <lajos@google.com> Mon May 06 16:23:07 2013 -0700
committer Android (Google) Code Review <android-gerrit@google.com> Thu May 23 22:21:13 2013 +0000
tree 77f8cc3eb06588a6982cc5df2fe24c3e3e2b5038
parent c5d7b7d323bba8772a9005f7d300ad983a04733a

BufferQueue: remove freeAllBuffersExceptHeadLocked()

Now that we are having separate buffer-instances for the buffer-
queue, we can free all buffers; we don't have to keep the head
alive.

Change-Id: I023e9161a2501d99333f8868ce438afa914ec50f
Signed-off-by: Lajos Molnar <lajos@google.com>
Related-to-bug: 7093648

libs/gui/BufferQueue.cpp

diff --git a/libs/gui/BufferQueue.cpp b/libs/gui/BufferQueue.cpp
index 34dbd71..0dab864 100644
--- a/libs/gui/BufferQueue.cpp
+++ b/libs/gui/BufferQueue.cpp
@@ -178,12 +178,10 @@
         }
 
         // here we're guaranteed that the client doesn't have dequeued buffers
-        // and will release all of its buffer references.
-        //
-        // XXX: Should this use drainQueueAndFreeBuffersLocked instead?
+        // and will release all of its buffer references.  We don't clear the
+        // queue, however, so currently queued buffers still get displayed.
         freeAllBuffersLocked();
         mOverrideMaxBufferCount = bufferCount;
-        mBufferHasBeenQueued = false;
         mDequeueCondition.broadcast();
         listener = mConsumerListener;
     } // scope for lock
@@ -801,9 +799,8 @@
 }
 
 void BufferQueue::freeAllBuffersLocked() {
-    ALOGW_IF(!mQueue.isEmpty(),
-            "freeAllBuffersLocked called but mQueue is not empty");
-    mQueue.clear();
+    ALOGD_IF(!mQueue.isEmpty(),
+            "freeAllBuffersLocked called with non-empty mQueue");
     mBufferHasBeenQueued = false;
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
         freeBufferLocked(i);
@@ -1026,18 +1023,6 @@
     return NO_ERROR;
 }
 
-void BufferQueue::freeAllBuffersExceptHeadLocked() {
-    // only called if mQueue is not empty
-    Fifo::iterator front(mQueue.begin());
-    mBufferHasBeenQueued = false;
-    for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
-        const BufferSlot &slot = mSlots[i];
-        if (slot.mGraphicBuffer == NULL ||
-            slot.mGraphicBuffer->handle != front->mGraphicBuffer->handle)
-            freeBufferLocked(i);
-    }
-}
-
 status_t BufferQueue::drainQueueLocked() {
     while (mSynchronousMode && mQueue.size() > 1) {
         mDequeueCondition.wait(mMutex);
@@ -1056,11 +1041,7 @@
 status_t BufferQueue::drainQueueAndFreeBuffersLocked() {
     status_t err = drainQueueLocked();
     if (err == NO_ERROR) {
-        if (mQueue.empty()) {
-            freeAllBuffersLocked();
-        } else {
-            freeAllBuffersExceptHeadLocked();
-        }
+        freeAllBuffersLocked();
     }
     return err;
 }