android.hardware.media.bufferpool@2.0 impl

Implementation is currently identical to 1.0 impl.
The update will be applied afterwards.

Bug: 112203066
Change-Id: If19af34121f5c9736ab4e8ccf7b1716d0be05c81
diff --git a/media/bufferpool/2.0/AccessorImpl.h b/media/bufferpool/2.0/AccessorImpl.h
new file mode 100644
index 0000000..4043940
--- /dev/null
+++ b/media/bufferpool/2.0/AccessorImpl.h
@@ -0,0 +1,300 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#ifndef ANDROID_HARDWARE_MEDIA_BUFFERPOOL_V2_0_ACCESSORIMPL_H
+#define ANDROID_HARDWARE_MEDIA_BUFFERPOOL_V2_0_ACCESSORIMPL_H
+
+#include <map>
+#include <set>
+#include "Accessor.h"
+
+namespace android {
+namespace hardware {
+namespace media {
+namespace bufferpool {
+namespace V2_0 {
+namespace implementation {
+
+struct InternalBuffer;
+struct TransactionStatus;
+
+/**
+ * An implementation of a buffer pool accessor(or a buffer pool implementation.) */
+class Accessor::Impl {
+public:
+    Impl(const std::shared_ptr<BufferPoolAllocator> &allocator);
+
+    ~Impl();
+
+    ResultStatus connect(
+            const sp<Accessor> &accessor, sp<Connection> *connection,
+            ConnectionId *pConnectionId, const QueueDescriptor** fmqDescPtr);
+
+    ResultStatus close(ConnectionId connectionId);
+
+    ResultStatus allocate(ConnectionId connectionId,
+                          const std::vector<uint8_t>& params,
+                          BufferId *bufferId,
+                          const native_handle_t** handle);
+
+    ResultStatus fetch(ConnectionId connectionId,
+                       TransactionId transactionId,
+                       BufferId bufferId,
+                       const native_handle_t** handle);
+
+    void cleanUp(bool clearCache);
+
+private:
+    // ConnectionId = pid : (timestamp_created + seqId)
+    // in order to guarantee uniqueness for each connection
+    static uint32_t sSeqId;
+    static int32_t sPid;
+
+    const std::shared_ptr<BufferPoolAllocator> mAllocator;
+
+    /**
+     * Buffer pool implementation.
+     *
+     * Handles buffer status messages. Handles buffer allocation/recycling.
+     * Handles buffer transfer between buffer pool clients.
+     */
+    struct BufferPool {
+    private:
+        std::mutex mMutex;
+        int64_t mTimestampUs;
+        int64_t mLastCleanUpUs;
+        int64_t mLastLogUs;
+        BufferId mSeq;
+        BufferStatusObserver mObserver;
+
+        std::map<ConnectionId, std::set<BufferId>> mUsingBuffers;
+        std::map<BufferId, std::set<ConnectionId>> mUsingConnections;
+
+        std::map<ConnectionId, std::set<TransactionId>> mPendingTransactions;
+        // Transactions completed before TRANSFER_TO message arrival.
+        // Fetch does not occur for the transactions.
+        // Only transaction id is kept for the transactions in short duration.
+        std::set<TransactionId> mCompletedTransactions;
+        // Currently active(pending) transations' status & information.
+        std::map<TransactionId, std::unique_ptr<TransactionStatus>>
+                mTransactions;
+
+        std::map<BufferId, std::unique_ptr<InternalBuffer>> mBuffers;
+        std::set<BufferId> mFreeBuffers;
+
+        /// Buffer pool statistics which tracks allocation and transfer statistics.
+        struct Stats {
+            /// Total size of allocations which are used or available to use.
+            /// (bytes or pixels)
+            size_t mSizeCached;
+            /// # of cached buffers which are used or available to use.
+            size_t mBuffersCached;
+            /// Total size of allocations which are currently used. (bytes or pixels)
+            size_t mSizeInUse;
+            /// # of currently used buffers
+            size_t mBuffersInUse;
+
+            /// # of allocations called on bufferpool. (# of fetched from BlockPool)
+            size_t mTotalAllocations;
+            /// # of allocations that were served from the cache.
+            /// (# of allocator alloc prevented)
+            size_t mTotalRecycles;
+            /// # of buffer transfers initiated.
+            size_t mTotalTransfers;
+            /// # of transfers that had to be fetched.
+            size_t mTotalFetches;
+
+            Stats()
+                : mSizeCached(0), mBuffersCached(0), mSizeInUse(0), mBuffersInUse(0),
+                  mTotalAllocations(0), mTotalRecycles(0), mTotalTransfers(0), mTotalFetches(0) {}
+
+            /// A new buffer is allocated on an allocation request.
+            void onBufferAllocated(size_t allocSize) {
+                mSizeCached += allocSize;
+                mBuffersCached++;
+
+                mSizeInUse += allocSize;
+                mBuffersInUse++;
+
+                mTotalAllocations++;
+            }
+
+            /// A buffer is evicted and destroyed.
+            void onBufferEvicted(size_t allocSize) {
+                mSizeCached -= allocSize;
+                mBuffersCached--;
+            }
+
+            /// A buffer is recycled on an allocation request.
+            void onBufferRecycled(size_t allocSize) {
+                mSizeInUse += allocSize;
+                mBuffersInUse++;
+
+                mTotalAllocations++;
+                mTotalRecycles++;
+            }
+
+            /// A buffer is available to be recycled.
+            void onBufferUnused(size_t allocSize) {
+                mSizeInUse -= allocSize;
+                mBuffersInUse--;
+            }
+
+            /// A buffer transfer is initiated.
+            void onBufferSent() {
+                mTotalTransfers++;
+            }
+
+            /// A buffer fetch is invoked by a buffer transfer.
+            void onBufferFetched() {
+                mTotalFetches++;
+            }
+        } mStats;
+
+    public:
+        /** Creates a buffer pool. */
+        BufferPool();
+
+        /** Destroys a buffer pool. */
+        ~BufferPool();
+
+        /**
+         * Processes all pending buffer status messages, and returns the result.
+         * Each status message is handled by methods with 'handle' prefix.
+         */
+        void processStatusMessages();
+
+        /**
+         * Handles a buffer being owned by a connection.
+         *
+         * @param connectionId  the id of the buffer owning connection.
+         * @param bufferId      the id of the buffer.
+         *
+         * @return {@code true} when the buffer is owned,
+         *         {@code false} otherwise.
+         */
+        bool handleOwnBuffer(ConnectionId connectionId, BufferId bufferId);
+
+        /**
+         * Handles a buffer being released by a connection.
+         *
+         * @param connectionId  the id of the buffer owning connection.
+         * @param bufferId      the id of the buffer.
+         *
+         * @return {@code true} when the buffer ownership is released,
+         *         {@code false} otherwise.
+         */
+        bool handleReleaseBuffer(ConnectionId connectionId, BufferId bufferId);
+
+        /**
+         * Handles a transfer transaction start message from the sender.
+         *
+         * @param message   a buffer status message for the transaction.
+         *
+         * @result {@code true} when transfer_to message is acknowledged,
+         *         {@code false} otherwise.
+         */
+        bool handleTransferTo(const BufferStatusMessage &message);
+
+        /**
+         * Handles a transfer transaction being acked by the receiver.
+         *
+         * @param message   a buffer status message for the transaction.
+         *
+         * @result {@code true} when transfer_from message is acknowledged,
+         *         {@code false} otherwise.
+         */
+        bool handleTransferFrom(const BufferStatusMessage &message);
+
+        /**
+         * Handles a transfer transaction result message from the receiver.
+         *
+         * @param message   a buffer status message for the transaction.
+         *
+         * @result {@code true} when the exisitng transaction is finished,
+         *         {@code false} otherwise.
+         */
+        bool handleTransferResult(const BufferStatusMessage &message);
+
+        /**
+         * Handles a connection being closed, and returns the result. All the
+         * buffers and transactions owned by the connection will be cleaned up.
+         * The related FMQ will be cleaned up too.
+         *
+         * @param connectionId  the id of the connection.
+         *
+         * @result {@code true} when the connection existed,
+         *         {@code false} otherwise.
+         */
+        bool handleClose(ConnectionId connectionId);
+
+        /**
+         * Recycles a existing free buffer if it is possible.
+         *
+         * @param allocator the buffer allocator
+         * @param params    the allocation parameters.
+         * @param pId       the id of the recycled buffer.
+         * @param handle    the native handle of the recycled buffer.
+         *
+         * @return {@code true} when a buffer is recycled, {@code false}
+         *         otherwise.
+         */
+        bool getFreeBuffer(
+                const std::shared_ptr<BufferPoolAllocator> &allocator,
+                const std::vector<uint8_t> &params,
+                BufferId *pId, const native_handle_t **handle);
+
+        /**
+         * Adds a newly allocated buffer to bufferpool.
+         *
+         * @param alloc     the newly allocated buffer.
+         * @param allocSize the size of the newly allocated buffer.
+         * @param params    the allocation parameters.
+         * @param pId       the buffer id for the newly allocated buffer.
+         * @param handle    the native handle for the newly allocated buffer.
+         *
+         * @return OK when an allocation is successfully allocated.
+         *         NO_MEMORY when there is no memory.
+         *         CRITICAL_ERROR otherwise.
+         */
+        ResultStatus addNewBuffer(
+                const std::shared_ptr<BufferPoolAllocation> &alloc,
+                const size_t allocSize,
+                const std::vector<uint8_t> &params,
+                BufferId *pId,
+                const native_handle_t **handle);
+
+        /**
+         * Processes pending buffer status messages and performs periodic cache
+         * cleaning.
+         *
+         * @param clearCache    if clearCache is true, it frees all buffers
+         *                      waiting to be recycled.
+         */
+        void cleanUp(bool clearCache = false);
+
+        friend class Accessor::Impl;
+    } mBufferPool;
+};
+
+}  // namespace implementation
+}  // namespace V2_0
+}  // namespace ufferpool
+}  // namespace media
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_MEDIA_BUFFERPOOL_V2_0_ACCESSORIMPL_H