don't return the current buffer from dequeueBuffer
we were not reseting mCurrentTexture in some situations
which in turn caused dequeueBuffers() return a
"FREE" buffer that was also current.
Very often it was harmless, but it created a race with
updateTexImage() which could cause the following
queueBuffers() to fail.
Bug: 5156325
Change-Id: If15a31dc869117543d220d6e5562c57116cbabdb
diff --git a/libs/gui/SurfaceTexture.cpp b/libs/gui/SurfaceTexture.cpp
index b2441ce..ac9b33b 100644
--- a/libs/gui/SurfaceTexture.cpp
+++ b/libs/gui/SurfaceTexture.cpp
@@ -36,6 +36,10 @@
#include <utils/Log.h>
#include <utils/String8.h>
+
+#define ALLOW_DEQUEUE_CURRENT_BUFFER false
+
+
namespace android {
// Transform matrices
@@ -294,9 +298,22 @@
if (state == BufferSlot::DEQUEUED) {
dequeuedCount++;
}
- if (state == BufferSlot::FREE /*|| i == mCurrentTexture*/) {
- foundSync = i;
- if (i != mCurrentTexture) {
+
+ // if buffer is FREE it CANNOT be current
+ LOGW_IF((state == BufferSlot::FREE) && (mCurrentTexture==i),
+ "dequeueBuffer: buffer %d is both FREE and current!", i);
+
+ if (ALLOW_DEQUEUE_CURRENT_BUFFER) {
+ if (state == BufferSlot::FREE || i == mCurrentTexture) {
+ foundSync = i;
+ if (i != mCurrentTexture) {
+ found = i;
+ break;
+ }
+ }
+ } else {
+ if (state == BufferSlot::FREE) {
+ foundSync = i;
found = i;
break;
}
@@ -325,7 +342,7 @@
}
// we're in synchronous mode and didn't find a buffer, we need to wait
- // for for some buffers to be consumed
+ // for some buffers to be consumed
tryAgain = mSynchronousMode && (foundSync == INVALID_BUFFER_SLOT);
if (tryAgain) {
mDequeueCondition.wait(mMutex);
@@ -846,6 +863,7 @@
void SurfaceTexture::freeAllBuffersLocked() {
LOGW_IF(!mQueue.isEmpty(),
"freeAllBuffersLocked called but mQueue is not empty");
+ mCurrentTexture = INVALID_BUFFER_SLOT;
for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
freeBufferLocked(i);
}
@@ -859,6 +877,7 @@
Fifo::iterator front(mQueue.begin());
head = *front;
}
+ mCurrentTexture = INVALID_BUFFER_SLOT;
for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
if (i != head) {
freeBufferLocked(i);