1 /* 2 * Copyright (C) 2023 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 SRC_TRACING_CORE_IN_PROCESS_SHARED_MEMORY_H_ 18 #define SRC_TRACING_CORE_IN_PROCESS_SHARED_MEMORY_H_ 19 20 #include <memory> 21 22 #include "perfetto/ext/base/paged_memory.h" 23 #include "perfetto/ext/tracing/core/shared_memory.h" 24 25 namespace perfetto { 26 27 // An implementation of the ShareMemory interface that allocates memory that can 28 // only be shared intra-process. 29 class InProcessSharedMemory : public SharedMemory { 30 public: 31 static constexpr size_t kDefaultSize = 128 * 1024; 32 33 // Default ctor used for intra-process shmem between a producer and the 34 // service. InProcessSharedMemory(size_t size)35 explicit InProcessSharedMemory(size_t size) 36 : mem_(base::PagedMemory::Allocate(size)) {} 37 ~InProcessSharedMemory() override; 38 39 static std::unique_ptr<InProcessSharedMemory> Create( 40 size_t size = kDefaultSize) { 41 return std::make_unique<InProcessSharedMemory>(size); 42 } 43 44 // SharedMemory implementation. 45 using SharedMemory::start; // Equal priority to const and non-const versions 46 const void* start() const override; 47 size_t size() const override; 48 49 class Factory : public SharedMemory::Factory { 50 public: 51 ~Factory() override; CreateSharedMemory(size_t size)52 std::unique_ptr<SharedMemory> CreateSharedMemory(size_t size) override { 53 return InProcessSharedMemory::Create(size); 54 } 55 }; 56 57 private: 58 base::PagedMemory mem_; 59 }; 60 61 } // namespace perfetto 62 63 #endif // SRC_TRACING_CORE_IN_PROCESS_SHARED_MEMORY_H_ 64