1 /*
2  * Copyright 2014,2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_SERVERS_STREAMSPLITTER_H
18 #define ANDROID_SERVERS_STREAMSPLITTER_H
19 
20 #include <unordered_set>
21 
22 #include <camera/CameraMetadata.h>
23 
24 #include <gui/IConsumerListener.h>
25 #include <gui/IProducerListener.h>
26 #include <gui/BufferItemConsumer.h>
27 
28 #include <utils/Condition.h>
29 #include <utils/Mutex.h>
30 #include <utils/StrongPointer.h>
31 #include <utils/Timers.h>
32 
33 #define SP_LOGV(x, ...) ALOGV("[%s] " x, mConsumerName.c_str(), ##__VA_ARGS__)
34 #define SP_LOGI(x, ...) ALOGI("[%s] " x, mConsumerName.c_str(), ##__VA_ARGS__)
35 #define SP_LOGW(x, ...) ALOGW("[%s] " x, mConsumerName.c_str(), ##__VA_ARGS__)
36 #define SP_LOGE(x, ...) ALOGE("[%s] " x, mConsumerName.c_str(), ##__VA_ARGS__)
37 
38 namespace android {
39 
40 class GraphicBuffer;
41 class IGraphicBufferConsumer;
42 class IGraphicBufferProducer;
43 
44 // Camera3StreamSplitter is an autonomous class that manages one input BufferQueue
45 // and multiple output BufferQueues. By using the buffer attach and detach logic
46 // in BufferQueue, it is able to present the illusion of a single split
47 // BufferQueue, where each buffer queued to the input is available to be
48 // acquired by each of the outputs, and is able to be dequeued by the input
49 // again only once all of the outputs have released it.
50 class Camera3StreamSplitter : public BnConsumerListener {
51 public:
52 
53     // Constructor
54     Camera3StreamSplitter(bool useHalBufManager = false);
55 
56     // Connect to the stream splitter by creating buffer queue and connecting it
57     // with output surfaces.
58     status_t connect(const std::unordered_map<size_t, sp<Surface>> &surfaces,
59             uint64_t consumerUsage, uint64_t producerUsage, size_t halMaxBuffers, uint32_t width,
60             uint32_t height, android::PixelFormat format, sp<Surface>* consumer,
61             int64_t dynamicRangeProfile);
62 
63     // addOutput adds an output BufferQueue to the splitter. The splitter
64     // connects to outputQueue as a CPU producer, and any buffers queued
65     // to the input will be queued to each output. If any  output is abandoned
66     // by its consumer, the splitter will abandon its input queue (see onAbandoned).
67     //
68     // A return value other than NO_ERROR means that an error has occurred and
69     // outputQueue has not been added to the splitter. BAD_VALUE is returned if
70     // outputQueue is NULL. See IGraphicBufferProducer::connect for explanations
71     // of other error codes.
72     status_t addOutput(size_t surfaceId, const sp<Surface>& outputQueue);
73 
74     //removeOutput will remove a BufferQueue that was previously added to
75     //the splitter outputs. Any pending buffers in the BufferQueue will get
76     //reclaimed.
77     status_t removeOutput(size_t surfaceId);
78 
79     // Notification that the graphic buffer has been released to the input
80     // BufferQueue. The buffer should be reused by the camera device instead of
81     // queuing to the outputs.
82     status_t notifyBufferReleased(const sp<GraphicBuffer>& buffer);
83 
84     // Attach a buffer to the specified outputs. This call reserves a buffer
85     // slot in the output queue.
86     status_t attachBufferToOutputs(ANativeWindowBuffer* anb,
87             const std::vector<size_t>& surface_ids);
88 
89     // Get return value of onFrameAvailable to work around problem that
90     // onFrameAvailable is void. This function should be called by the producer
91     // right after calling queueBuffer().
92     status_t getOnFrameAvailableResult();
93 
94     // Disconnect the buffer queue from output surfaces.
95     void disconnect();
96 
97     void setHalBufferManager(bool enabled);
98 
99 private:
100     // From IConsumerListener
101     //
102     // During this callback, we store some tracking information, detach the
103     // buffer from the input, and attach it to each of the outputs. This call
104     // can block if there are too many outstanding buffers. If it blocks, it
105     // will resume when onBufferReleasedByOutput releases a buffer back to the
106     // input.
107     void onFrameAvailable(const BufferItem& item) override;
108 
109     // From IConsumerListener
110     //
111     // Similar to onFrameAvailable, but buffer item is indeed replacing a buffer
112     // in the buffer queue. This can happen when buffer queue is in droppable
113     // mode.
114     void onFrameReplaced(const BufferItem& item) override;
115 
116     // From IConsumerListener
117     // We don't care about released buffers because we detach each buffer as
118     // soon as we acquire it. See the comment for onBufferReleased below for
119     // some clarifying notes about the name.
onBuffersReleased()120     void onBuffersReleased() override {}
121 
122     // From IConsumerListener
123     // We don't care about sideband streams, since we won't be splitting them
onSidebandStreamChanged()124     void onSidebandStreamChanged() override {}
125 
126     // This is the implementation of the onBufferReleased callback from
127     // IProducerListener. It gets called from an OutputListener (see below), and
128     // 'from' is which producer interface from which the callback was received.
129     //
130     // During this callback, we detach the buffer from the output queue that
131     // generated the callback, update our state tracking to see if this is the
132     // last output releasing the buffer, and if so, release it to the input.
133     // If we release the buffer to the input, we allow a blocked
134     // onFrameAvailable call to proceed.
135     void onBufferReleasedByOutput(const sp<IGraphicBufferProducer>& from);
136 
137     // Called by outputBufferLocked when a buffer in the async buffer queue got replaced.
138     void onBufferReplacedLocked(const sp<IGraphicBufferProducer>& from, size_t surfaceId);
139 
140     // When this is called, the splitter disconnects from (i.e., abandons) its
141     // input queue and signals any waiting onFrameAvailable calls to wake up.
142     // It still processes callbacks from other outputs, but only detaches their
143     // buffers so they can continue operating until they run out of buffers to
144     // acquire. This must be called with mMutex locked.
145     void onAbandonedLocked();
146 
147     // Decrement the buffer's reference count. Once the reference count becomes
148     // 0, return the buffer back to the input BufferQueue.
149     void decrementBufRefCountLocked(uint64_t id, size_t surfaceId);
150 
151     // Check for and handle any output surface dequeue errors.
152     void handleOutputDequeueStatusLocked(status_t res, int slot);
153 
154     // Handles released output surface buffers.
155     void returnOutputBufferLocked(const sp<Fence>& fence, const sp<IGraphicBufferProducer>& from,
156             size_t surfaceId, int slot);
157 
158     // This is a thin wrapper class that lets us determine which BufferQueue
159     // the IProducerListener::onBufferReleased callback is associated with. We
160     // create one of these per output BufferQueue, and then pass the producer
161     // into onBufferReleasedByOutput above.
162     class OutputListener : public BnProducerListener,
163                            public IBinder::DeathRecipient {
164     public:
165         OutputListener(wp<Camera3StreamSplitter> splitter,
166                 wp<IGraphicBufferProducer> output);
167         virtual ~OutputListener() = default;
168 
169         // From IProducerListener
170         void onBufferReleased() override;
171 
172         // From IBinder::DeathRecipient
173         void binderDied(const wp<IBinder>& who) override;
174 
175     private:
176         wp<Camera3StreamSplitter> mSplitter;
177         wp<IGraphicBufferProducer> mOutput;
178     };
179 
180     class BufferTracker {
181     public:
182         BufferTracker(const sp<GraphicBuffer>& buffer,
183                 const std::vector<size_t>& requestedSurfaces);
184         ~BufferTracker() = default;
185 
getBuffer()186         const sp<GraphicBuffer>& getBuffer() const { return mBuffer; }
getMergedFence()187         const sp<Fence>& getMergedFence() const { return mMergedFence; }
188 
189         void mergeFence(const sp<Fence>& with);
190 
191         // Returns the new value
192         // Only called while mMutex is held
193         size_t decrementReferenceCountLocked(size_t surfaceId);
194 
requestedSurfaces()195         const std::vector<size_t> requestedSurfaces() const { return mRequestedSurfaces; }
196 
197     private:
198 
199         // Disallow copying
200         BufferTracker(const BufferTracker& other);
201         BufferTracker& operator=(const BufferTracker& other);
202 
203         sp<GraphicBuffer> mBuffer; // One instance that holds this native handle
204         sp<Fence> mMergedFence;
205 
206         // Request surfaces for a particular buffer. And when the buffer becomes
207         // available from the input queue, the registered surfaces are used to decide
208         // which output is the buffer sent to.
209         std::vector<size_t> mRequestedSurfaces;
210         size_t mReferenceCount;
211     };
212 
213     // Must be accessed through RefBase
214     virtual ~Camera3StreamSplitter();
215 
216     status_t addOutputLocked(size_t surfaceId, const sp<Surface>& outputQueue);
217 
218     status_t removeOutputLocked(size_t surfaceId);
219 
220     // Send a buffer to particular output, and increment the reference count
221     // of the buffer. If this output is abandoned, the buffer's reference count
222     // won't be incremented.
223     status_t outputBufferLocked(const sp<IGraphicBufferProducer>& output,
224             const BufferItem& bufferItem, size_t surfaceId);
225 
226     // Get unique name for the buffer queue consumer
227     std::string getUniqueConsumerName();
228 
229     // Helper function to get the BufferQueue slot where a particular buffer is attached to.
230     int getSlotForOutputLocked(const sp<IGraphicBufferProducer>& gbp,
231             const sp<GraphicBuffer>& gb);
232 
233     // Sum of max consumer buffers for all outputs
234     size_t mMaxConsumerBuffers = 0;
235     size_t mMaxHalBuffers = 0;
236     uint32_t mWidth = 0;
237     uint32_t mHeight = 0;
238     android::PixelFormat mFormat = android::PIXEL_FORMAT_NONE;
239     uint64_t mProducerUsage = 0;
240     int mDynamicRangeProfile = ANDROID_REQUEST_AVAILABLE_DYNAMIC_RANGE_PROFILES_MAP_STANDARD;
241 
242     // The attachBuffer call will happen on different thread according to mUseHalBufManager and have
243     // different timing constraint.
244     static const nsecs_t kNormalDequeueBufferTimeout    = s2ns(1);  // 1 sec
245     static const nsecs_t kHalBufMgrDequeueBufferTimeout = ms2ns(1); // 1 msec
246 
247     Mutex mMutex;
248 
249     sp<IGraphicBufferProducer> mProducer;
250     sp<IGraphicBufferConsumer> mConsumer;
251     sp<BufferItemConsumer> mBufferItemConsumer;
252     sp<Surface> mSurface;
253 
254     //Map graphic buffer ids -> buffer items
255     std::unordered_map<uint64_t, BufferItem> mInputSlots;
256 
257     //Map surface ids -> gbp outputs
258     std::unordered_map<int, sp<IGraphicBufferProducer> > mOutputs;
259 
260     //Map surface ids -> gbp outputs
261     std::unordered_map<int, sp<Surface>> mOutputSurfaces;
262 
263     //Map surface ids -> consumer buffer count
264     std::unordered_map<int, size_t > mConsumerBufferCount;
265 
266     // Map of GraphicBuffer IDs (GraphicBuffer::getId()) to buffer tracking
267     // objects (which are mostly for counting how many outputs have released the
268     // buffer, but also contain merged release fences).
269     std::unordered_map<uint64_t, std::unique_ptr<BufferTracker> > mBuffers;
270 
271     struct GBPHash {
operatorGBPHash272         std::size_t operator()(const sp<IGraphicBufferProducer>& producer) const {
273             return std::hash<IGraphicBufferProducer *>{}(producer.get());
274         }
275     };
276 
277     std::unordered_map<sp<IGraphicBufferProducer>, sp<OutputListener>,
278             GBPHash> mNotifiers;
279 
280     typedef std::vector<sp<GraphicBuffer>> OutputSlots;
281     std::unordered_map<sp<IGraphicBufferProducer>, std::unique_ptr<OutputSlots>,
282             GBPHash> mOutputSlots;
283 
284     //A set of buffers that could potentially stay in some of the outputs after removal
285     //and therefore should be detached from the input queue.
286     std::unordered_set<uint64_t> mDetachedBuffers;
287 
288     // Latest onFrameAvailable return value
289     std::atomic<status_t> mOnFrameAvailableRes{0};
290 
291     // Currently acquired input buffers
292     size_t mAcquiredInputBuffers;
293 
294     std::string mConsumerName;
295 
296     bool mUseHalBufManager;
297 };
298 
299 } // namespace android
300 
301 #endif
302