1 /* 2 * Copyright (C) 2017 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 #pragma once 18 19 #include <GrContextOptions.h> 20 #include <SkRefCnt.h> 21 #include <cutils/compiler.h> 22 #include <ftl/shared_mutex.h> 23 #include <utils/Mutex.h> 24 25 #include <memory> 26 #include <string> 27 #include <vector> 28 29 class SkData; 30 31 namespace android { 32 33 class BlobCache; 34 class FileBlobCache; 35 36 namespace uirenderer { 37 namespace skiapipeline { 38 39 class ShaderCache : public GrContextOptions::PersistentCache { 40 public: 41 /** 42 * "get" returns a pointer to the singleton ShaderCache object. This 43 * singleton object will never be destroyed. 44 */ 45 static ShaderCache& get(); 46 47 /** 48 * initShaderDiskCache" loads the serialized cache contents from disk, 49 * optionally checks that the on-disk cache matches a provided identity, 50 * and puts the ShaderCache into an initialized state, such that it is 51 * able to insert and retrieve entries from the cache. If identity is 52 * non-null and validation fails, the cache is initialized but contains 53 * no data. If size is less than zero, the cache is initialized but 54 * contains no data. 55 * 56 * This should be called when HWUI pipeline is initialized. When not in 57 * the initialized state the load and store methods will return without 58 * performing any cache operations. 59 */ 60 virtual void initShaderDiskCache(const void* identity, ssize_t size); 61 initShaderDiskCache()62 virtual void initShaderDiskCache() { initShaderDiskCache(nullptr, 0); } 63 64 /** 65 * "setFilename" sets the name of the file that should be used to store 66 * cache contents from one program invocation to another. This function does not perform any 67 * disk operation and it should be invoked before "initShaderCache". 68 */ 69 virtual void setFilename(const char* filename); 70 71 /** 72 * "load" attempts to retrieve the value blob associated with a given key 73 * blob from cache. This will be called by Skia, when it needs to compile a new SKSL shader. 74 */ 75 sk_sp<SkData> load(const SkData& key) override; 76 77 /** 78 * "store" attempts to insert a new key/value blob pair into the cache. 79 * This will be called by Skia after it compiled a new SKSL shader 80 */ 81 void store(const SkData& key, const SkData& data, const SkString& description) override; 82 83 /** 84 * "onVkFrameFlushed" tries to store Vulkan pipeline cache state. 85 * Pipeline cache is saved on disk only if the size of the data has changed or there was 86 * a new shader compiled. 87 */ 88 void onVkFrameFlushed(GrDirectContext* context); 89 90 private: 91 // Creation and (the lack of) destruction is handled internally. 92 ShaderCache(); 93 94 // Copying is disallowed. 95 ShaderCache(const ShaderCache&) = delete; 96 void operator=(const ShaderCache&) = delete; 97 98 /** 99 * "validateCache" updates the cache to match the given identity. If the 100 * cache currently has the wrong identity, all entries in the cache are cleared. 101 */ 102 bool validateCache(const void* identity, ssize_t size) REQUIRES(mMutex); 103 104 /** 105 * Helper for BlobCache::set to trace the result and ensure the identity hash 106 * does not get evicted. 107 */ 108 void set(const void* key, size_t keySize, const void* value, size_t valueSize) REQUIRES(mMutex); 109 110 /** 111 * "saveToDiskLocked" attempts to save the current contents of the cache to 112 * disk. If the identity hash exists, we will insert the identity hash into 113 * the cache for next validation. 114 */ 115 void saveToDiskLocked() REQUIRES(mMutex); 116 117 /** 118 * "mInitialized" indicates whether the ShaderCache is in the initialized 119 * state. It is initialized to false at construction time, and gets set to 120 * true when initialize is called. 121 * When in this state, the cache behaves as normal. When not, 122 * the load and store methods will return without performing any cache 123 * operations. 124 */ 125 bool mInitialized GUARDED_BY(mMutex) = false; 126 127 /** 128 * "mBlobCache" is the cache in which the key/value blob pairs are stored. 129 * The blob cache contains the Android build number. We treat version mismatches 130 * as an empty cache (logic implemented in BlobCache::unflatten). 131 */ 132 std::unique_ptr<FileBlobCache> mBlobCache GUARDED_BY(mMutex); 133 134 /** 135 * "mFilename" is the name of the file for storing cache contents in between 136 * program invocations. It is initialized to an empty string at 137 * construction time, and can be set with the setCacheFilename method. An 138 * empty string indicates that the cache should not be saved to or restored 139 * from disk. 140 */ 141 std::string mFilename GUARDED_BY(mMutex); 142 143 /** 144 * "mIDHash" is the current identity hash for the cache validation. It is 145 * initialized to an empty vector at construction time, and its content is 146 * generated in the call of the validateCache method. An empty vector 147 * indicates that cache validation is not performed, and the hash should 148 * not be stored on disk. 149 */ 150 std::vector<uint8_t> mIDHash GUARDED_BY(mMutex); 151 152 /** 153 * "mSavePending" indicates whether or not a deferred save operation is 154 * pending. Each time a key/value pair is inserted into the cache via 155 * load, a deferred save is initiated if one is not already pending. 156 * This will wait some amount of time and then trigger a save of the cache 157 * contents to disk, unless mDeferredSaveDelayMs is 0 in which case saving 158 * is disabled. 159 */ 160 bool mSavePending GUARDED_BY(mMutex) = false; 161 162 /** 163 * "mObservedBlobValueSize" is the maximum value size observed by the cache reading function. 164 */ 165 size_t mObservedBlobValueSize = 20 * 1024; 166 167 /** 168 * The time in milliseconds to wait before saving newly inserted cache entries. 169 * 170 * WARNING: setting this to 0 will disable writing the cache to disk. 171 */ 172 unsigned int mDeferredSaveDelayMs = 4 * 1000; 173 174 /** 175 * "mMutex" is the shared mutex used to prevent concurrent access to the member 176 * variables. It must be locked whenever the member variables are accessed. 177 */ 178 mutable ftl::SharedMutex mMutex; 179 180 /** 181 * If set to "true", the next call to onVkFrameFlushed, will invoke 182 * GrCanvas::storeVkPipelineCacheData. This does not guarantee that data will be stored on disk. 183 */ 184 bool mTryToStorePipelineCache GUARDED_BY(mMutex) = true; 185 186 /** 187 * This flag is used by "ShaderCache::store" to distinguish between shader data and 188 * Vulkan pipeline data. 189 */ 190 bool mInStoreVkPipelineInProgress = false; 191 192 /** 193 * "mNewPipelineCacheSize" has the size of the new Vulkan pipeline cache data. It is used 194 * to prevent unnecessary disk writes, if the pipeline cache size has not changed. 195 */ 196 size_t mNewPipelineCacheSize GUARDED_BY(mMutex) = -1; 197 /** 198 * "mOldPipelineCacheSize" has the size of the Vulkan pipeline cache data stored on disk. 199 */ 200 size_t mOldPipelineCacheSize GUARDED_BY(mMutex) = -1; 201 202 /** 203 * "mCacheDirty" is true when there is new shader cache data, which is not saved to disk. 204 */ 205 bool mCacheDirty GUARDED_BY(mMutex) = false; 206 207 /** 208 * "sCache" is the singleton ShaderCache object. 209 */ 210 static ShaderCache sCache; 211 212 /** 213 * "sIDKey" is the cache key of the identity hash 214 */ 215 static constexpr uint8_t sIDKey = 0; 216 217 /** 218 * Most of this class concerns persistent storage for shaders, but it's also 219 * interesting to keep track of how many shaders are stored in RAM. This 220 * class provides a convenient entry point for that. 221 */ 222 int mNumShadersCachedInRam GUARDED_BY(mMutex) = 0; 223 224 friend class ShaderCacheTestUtils; // used for unit testing 225 }; 226 227 } /* namespace skiapipeline */ 228 } /* namespace uirenderer */ 229 } /* namespace android */ 230