1 /* 2 * Copyright (C) 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 #ifndef ANDROID_HARDWARE_CACHE_MAPPING_H 17 #define ANDROID_HARDWARE_CACHE_MAPPING_H 18 19 #include <android/hidl/memory/1.0/IMemory.h> 20 #include <android/hidl/memory/block/1.0/types.h> 21 #include <android/hidl/memory/token/1.0/IMemoryToken.h> 22 23 namespace android { 24 namespace hardware { 25 26 /** 27 * Returns the IMemory instance corresponding to a MemoryBlock. The heap that 28 * a MemoryBlock belongs to is stored in an internal cache to reduce the number 29 * of invocations to the mapMemory(hidl_memory) 30 * 31 * Note, a cache entry is maintained by reference count and may be flushed when 32 * the count decrease to zero. Performance critical part that does not want its 33 * caches to be flushed can use HidlMemoryCacheLock. 34 */ 35 sp<::android::hidl::memory::V1_0::IMemory> mapMemory( 36 const ::android::hidl::memory::block::V1_0::MemoryBlock& block); 37 38 /** 39 * Internally, there's a cache pool to keep IMemory instances for heap regions 40 * that are referred by the MemoryBlock. During development, this 41 * lockMemoryCache(...) method helps to diagnosis whether the cache is effective 42 * for a specific key. It returns a RAII object used to lock an IMemory instance 43 * referred by the key and keep it alive even if the instance is not referred by 44 * any MemoryBlock. If the cache in interest is already effective. It won't differ 45 * much in performance w/ wo/ the lockMemoryCache() 46 * 47 * @note An IMemory instance that is returned from the mapMemory() is 48 * initialized in an unlocked state. 49 */ 50 sp<RefBase> lockMemoryCache(const sp<::android::hidl::memory::token::V1_0::IMemoryToken> key); 51 52 } // namespace hardware 53 } // namespace android 54 #endif 55
