Change slot generation for BufferState

BufferState layers now do slot generation with buffer death considered
appropriately.  When a buffer dies, the slot will be pushed onto a stack
of available slots to be reused at the next opportunity.  This should
mimic BufferQueue slot behavior and prevent Composer Resources from
growing too large.

Test: build, boot, manual
Bug: 129351223

Change-Id: Icef9592593cacb0b5c6b12f6679fc2c4dabdcd19

1 files changed, 78 insertions, 0 deletions

diff --git a/services/surfaceflinger/ClientCache.h b/services/surfaceflinger/ClientCache.h
new file mode 100644
index 0000000000..9f057c45d4
--- /dev/null
+++ b/services/surfaceflinger/ClientCache.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright 2019 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.
+ */
+
+#pragma once
+
+#include <android-base/thread_annotations.h>
+#include <binder/IBinder.h>
+#include <gui/LayerState.h>
+#include <ui/GraphicBuffer.h>
+#include <utils/RefBase.h>
+#include <utils/Singleton.h>
+
+#include <map>
+#include <mutex>
+#include <set>
+#include <unordered_map>
+
+#define BUFFER_CACHE_MAX_SIZE 64
+
+namespace android {
+
+class ClientCache : public Singleton<ClientCache> {
+public:
+    ClientCache();
+
+    void add(const client_cache_t& cacheId, const sp<GraphicBuffer>& buffer);
+    void erase(const client_cache_t& cacheId);
+
+    sp<GraphicBuffer> get(const client_cache_t& cacheId);
+
+    void removeProcess(const wp<IBinder>& processToken);
+
+    class ErasedRecipient : public virtual RefBase {
+    public:
+        virtual void bufferErased(const client_cache_t& clientCacheId) = 0;
+    };
+
+    void registerErasedRecipient(const client_cache_t& cacheId,
+                                 const wp<ErasedRecipient>& recipient);
+    void unregisterErasedRecipient(const client_cache_t& cacheId,
+                                   const wp<ErasedRecipient>& recipient);
+
+private:
+    std::mutex mMutex;
+
+    struct ClientCacheBuffer {
+        sp<GraphicBuffer> buffer;
+        std::set<wp<ErasedRecipient>> recipients;
+    };
+    std::map<wp<IBinder> /*caching process*/,
+             std::unordered_map<uint64_t /*cache id*/, ClientCacheBuffer>>
+            mBuffers GUARDED_BY(mMutex);
+
+    class CacheDeathRecipient : public IBinder::DeathRecipient {
+    public:
+        void binderDied(const wp<IBinder>& who) override;
+    };
+
+    sp<CacheDeathRecipient> mDeathRecipient;
+
+    bool getBuffer(const client_cache_t& cacheId, ClientCacheBuffer** outClientCacheBuffer)
+            REQUIRES(mMutex);
+};
+
+}; // namespace android