replicant-frameworks_native/libs/gui/ConsumerBase.cpp
Jesse Hall 9504eb915c Fix race condition in ConsumerBase::addReleaseFence()
This needs the ConsumerBase mutex locked, but wasn't locking it. Two
of the four places that called it already held the lock so were fine.
Now addReleaseFence() takes the lock itself, and I added
addReleaseFenceLocked() for the two already-locked callers, since in
one of them dropping the lock would be inconvenient.

Bug: 7289269
Change-Id: I7a5628adb516f8eec782aa6c14128202f96d7b0a
2012-10-05 14:40:50 -07:00

236 lines
6.9 KiB
C++

/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "ConsumerBase"
#define ATRACE_TAG ATRACE_TAG_GRAPHICS
//#define LOG_NDEBUG 0
#define GL_GLEXT_PROTOTYPES
#define EGL_EGLEXT_PROTOTYPES
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <hardware/hardware.h>
#include <gui/IGraphicBufferAlloc.h>
#include <gui/ISurfaceComposer.h>
#include <gui/SurfaceComposerClient.h>
#include <gui/ConsumerBase.h>
#include <private/gui/ComposerService.h>
#include <utils/Log.h>
#include <utils/String8.h>
#include <utils/Trace.h>
// Macros for including the ConsumerBase name in log messages
#define CB_LOGV(x, ...) ALOGV("[%s] "x, mName.string(), ##__VA_ARGS__)
#define CB_LOGD(x, ...) ALOGD("[%s] "x, mName.string(), ##__VA_ARGS__)
#define CB_LOGI(x, ...) ALOGI("[%s] "x, mName.string(), ##__VA_ARGS__)
#define CB_LOGW(x, ...) ALOGW("[%s] "x, mName.string(), ##__VA_ARGS__)
#define CB_LOGE(x, ...) ALOGE("[%s] "x, mName.string(), ##__VA_ARGS__)
namespace android {
// Get an ID that's unique within this process.
static int32_t createProcessUniqueId() {
static volatile int32_t globalCounter = 0;
return android_atomic_inc(&globalCounter);
}
ConsumerBase::ConsumerBase(const sp<BufferQueue>& bufferQueue) :
mAbandoned(false),
mBufferQueue(bufferQueue) {
// Choose a name using the PID and a process-unique ID.
mName = String8::format("unnamed-%d-%d", getpid(), createProcessUniqueId());
// Note that we can't create an sp<...>(this) in a ctor that will not keep a
// reference once the ctor ends, as that would cause the refcount of 'this'
// dropping to 0 at the end of the ctor. Since all we need is a wp<...>
// that's what we create.
wp<BufferQueue::ConsumerListener> listener;
sp<BufferQueue::ConsumerListener> proxy;
listener = static_cast<BufferQueue::ConsumerListener*>(this);
proxy = new BufferQueue::ProxyConsumerListener(listener);
status_t err = mBufferQueue->consumerConnect(proxy);
if (err != NO_ERROR) {
CB_LOGE("SurfaceTexture: error connecting to BufferQueue: %s (%d)",
strerror(-err), err);
} else {
mBufferQueue->setConsumerName(mName);
}
}
ConsumerBase::~ConsumerBase() {
CB_LOGV("~ConsumerBase");
abandon();
}
void ConsumerBase::freeBufferLocked(int slotIndex) {
CB_LOGV("freeBufferLocked: slotIndex=%d", slotIndex);
mSlots[slotIndex].mGraphicBuffer = 0;
mSlots[slotIndex].mFence = 0;
}
// Used for refactoring, should not be in final interface
sp<BufferQueue> ConsumerBase::getBufferQueue() const {
Mutex::Autolock lock(mMutex);
return mBufferQueue;
}
void ConsumerBase::onFrameAvailable() {
CB_LOGV("onFrameAvailable");
sp<FrameAvailableListener> listener;
{ // scope for the lock
Mutex::Autolock lock(mMutex);
listener = mFrameAvailableListener;
}
if (listener != NULL) {
CB_LOGV("actually calling onFrameAvailable");
listener->onFrameAvailable();
}
}
void ConsumerBase::onBuffersReleased() {
Mutex::Autolock lock(mMutex);
CB_LOGV("onBuffersReleased");
if (mAbandoned) {
// Nothing to do if we're already abandoned.
return;
}
uint32_t mask = 0;
mBufferQueue->getReleasedBuffers(&mask);
for (int i = 0; i < BufferQueue::NUM_BUFFER_SLOTS; i++) {
if (mask & (1 << i)) {
freeBufferLocked(i);
}
}
}
void ConsumerBase::abandon() {
CB_LOGV("abandon");
Mutex::Autolock lock(mMutex);
if (!mAbandoned) {
abandonLocked();
mAbandoned = true;
}
}
void ConsumerBase::abandonLocked() {
CB_LOGV("abandonLocked");
for (int i =0; i < BufferQueue::NUM_BUFFER_SLOTS; i++) {
freeBufferLocked(i);
}
// disconnect from the BufferQueue
mBufferQueue->consumerDisconnect();
mBufferQueue.clear();
}
void ConsumerBase::setFrameAvailableListener(
const sp<FrameAvailableListener>& listener) {
CB_LOGV("setFrameAvailableListener");
Mutex::Autolock lock(mMutex);
mFrameAvailableListener = listener;
}
void ConsumerBase::dump(String8& result) const {
char buffer[1024];
dump(result, "", buffer, 1024);
}
void ConsumerBase::dump(String8& result, const char* prefix,
char* buffer, size_t size) const {
Mutex::Autolock _l(mMutex);
dumpLocked(result, prefix, buffer, size);
}
void ConsumerBase::dumpLocked(String8& result, const char* prefix,
char* buffer, size_t SIZE) const {
snprintf(buffer, SIZE, "%smAbandoned=%d\n", prefix, int(mAbandoned));
result.append(buffer);
if (!mAbandoned) {
mBufferQueue->dump(result, prefix, buffer, SIZE);
}
}
status_t ConsumerBase::acquireBufferLocked(BufferQueue::BufferItem *item) {
status_t err = mBufferQueue->acquireBuffer(item);
if (err != NO_ERROR) {
return err;
}
if (item->mGraphicBuffer != NULL) {
mSlots[item->mBuf].mGraphicBuffer = item->mGraphicBuffer;
}
mSlots[item->mBuf].mFence = item->mFence;
CB_LOGV("acquireBufferLocked: -> slot=%d", item->mBuf);
return OK;
}
status_t ConsumerBase::addReleaseFence(int slot, const sp<Fence>& fence) {
Mutex::Autolock lock(mMutex);
return addReleaseFenceLocked(slot, fence);
}
status_t ConsumerBase::addReleaseFenceLocked(int slot, const sp<Fence>& fence) {
CB_LOGV("addReleaseFenceLocked: slot=%d", slot);
if (!mSlots[slot].mFence.get()) {
mSlots[slot].mFence = fence;
} else {
sp<Fence> mergedFence = Fence::merge(
String8::format("%.28s:%d", mName.string(), slot),
mSlots[slot].mFence, fence);
if (!mergedFence.get()) {
CB_LOGE("failed to merge release fences");
// synchronization is broken, the best we can do is hope fences
// signal in order so the new fence will act like a union
mSlots[slot].mFence = fence;
return BAD_VALUE;
}
mSlots[slot].mFence = mergedFence;
}
return OK;
}
status_t ConsumerBase::releaseBufferLocked(int slot, EGLDisplay display,
EGLSyncKHR eglFence) {
CB_LOGV("releaseBufferLocked: slot=%d", slot);
status_t err = mBufferQueue->releaseBuffer(slot, display, eglFence,
mSlots[slot].mFence);
if (err == BufferQueue::STALE_BUFFER_SLOT) {
freeBufferLocked(slot);
}
mSlots[slot].mFence.clear();
return err;
}
} // namespace android