libgui: Allow an IGBProducer to disable allocation
Adds a new method IGBP::allowAllocation, which controls whether
dequeueBuffer is permitted to allocate a new buffer. If allocation is
disallowed, dequeueBuffer will block or return an error as it
normally would (as controlled by *ControlledByApp).
If there are free buffers, but they are not of the correct dimensions,
format, or usage, they may be freed if a more suitable buffer is not
found first.
Bug: 19801715
Change-Id: I0d604958b78b2fd775c2547690301423f9a52165
diff --git a/libs/gui/BufferQueueProducer.cpp b/libs/gui/BufferQueueProducer.cpp
index a27d5f0..86e45c8 100644
--- a/libs/gui/BufferQueueProducer.cpp
+++ b/libs/gui/BufferQueueProducer.cpp
@@ -219,7 +219,7 @@
auto slot = mCore->mFreeBuffers.begin();
*found = *slot;
mCore->mFreeBuffers.erase(slot);
- } else if (!mCore->mFreeSlots.empty()) {
+ } else if (mCore->mAllowAllocation && !mCore->mFreeSlots.empty()) {
auto slot = mCore->mFreeSlots.begin();
// Only return free slots up to the max buffer count
if (*slot < maxBufferCount) {
@@ -285,17 +285,39 @@
// Enable the usage bits the consumer requested
usage |= mCore->mConsumerUsageBits;
- int found;
- status_t status = waitForFreeSlotThenRelock("dequeueBuffer", async,
- &found, &returnFlags);
- if (status != NO_ERROR) {
- return status;
+ const bool useDefaultSize = !width && !height;
+ if (useDefaultSize) {
+ width = mCore->mDefaultWidth;
+ height = mCore->mDefaultHeight;
}
- // This should not happen
- if (found == BufferQueueCore::INVALID_BUFFER_SLOT) {
- BQ_LOGE("dequeueBuffer: no available buffer slots");
- return -EBUSY;
+ int found = BufferItem::INVALID_BUFFER_SLOT;
+ while (found == BufferItem::INVALID_BUFFER_SLOT) {
+ status_t status = waitForFreeSlotThenRelock("dequeueBuffer", async,
+ &found, &returnFlags);
+ if (status != NO_ERROR) {
+ return status;
+ }
+
+ // This should not happen
+ if (found == BufferQueueCore::INVALID_BUFFER_SLOT) {
+ BQ_LOGE("dequeueBuffer: no available buffer slots");
+ return -EBUSY;
+ }
+
+ const sp<GraphicBuffer>& buffer(mSlots[found].mGraphicBuffer);
+
+ // If we are not allowed to allocate new buffers,
+ // waitForFreeSlotThenRelock must have returned a slot containing a
+ // buffer. If this buffer would require reallocation to meet the
+ // requested attributes, we free it and attempt to get another one.
+ if (!mCore->mAllowAllocation) {
+ if (buffer->needsReallocation(width, height, format, usage)) {
+ mCore->freeBufferLocked(found);
+ found = BufferItem::INVALID_BUFFER_SLOT;
+ continue;
+ }
+ }
}
*outSlot = found;
@@ -303,20 +325,11 @@
attachedByConsumer = mSlots[found].mAttachedByConsumer;
- const bool useDefaultSize = !width && !height;
- if (useDefaultSize) {
- width = mCore->mDefaultWidth;
- height = mCore->mDefaultHeight;
- }
-
mSlots[found].mBufferState = BufferSlot::DEQUEUED;
const sp<GraphicBuffer>& buffer(mSlots[found].mGraphicBuffer);
if ((buffer == NULL) ||
- (static_cast<uint32_t>(buffer->width) != width) ||
- (static_cast<uint32_t>(buffer->height) != height) ||
- (buffer->format != format) ||
- ((static_cast<uint32_t>(buffer->usage) & usage) != usage))
+ buffer->needsReallocation(width, height, format, usage))
{
mSlots[found].mAcquireCalled = false;
mSlots[found].mGraphicBuffer = NULL;
@@ -933,6 +946,12 @@
Mutex::Autolock lock(mCore->mMutex);
mCore->waitWhileAllocatingLocked();
+ if (!mCore->mAllowAllocation) {
+ BQ_LOGE("allocateBuffers: allocation is not allowed for this "
+ "BufferQueue");
+ return;
+ }
+
int currentBufferCount = 0;
for (int slot = 0; slot < BufferQueueDefs::NUM_BUFFER_SLOTS; ++slot) {
if (mSlots[slot].mGraphicBuffer != NULL) {
@@ -1027,6 +1046,15 @@
}
}
+status_t BufferQueueProducer::allowAllocation(bool allow) {
+ ATRACE_CALL();
+ BQ_LOGV("allowAllocation: %s", allow ? "true" : "false");
+
+ Mutex::Autolock lock(mCore->mMutex);
+ mCore->mAllowAllocation = allow;
+ return NO_ERROR;
+}
+
void BufferQueueProducer::binderDied(const wp<android::IBinder>& /* who */) {
// If we're here, it means that a producer we were connected to died.
// We're guaranteed that we are still connected to it because we remove