1 /* 2 * Copyright 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 17 #ifndef ART_COMPILER_JIT_JIT_LOGGER_H_ 18 #define ART_COMPILER_JIT_JIT_LOGGER_H_ 19 20 #include <memory> 21 22 #include "base/mutex.h" 23 #include "base/os.h" 24 #include "compiled_method.h" 25 26 namespace art { 27 28 class ArtMethod; 29 30 namespace jit { 31 32 // 33 // JitLogger supports two approaches of perf profiling. 34 // 35 // (1) perf-map: 36 // The perf-map mechanism generates perf-PID.map file, 37 // which provides simple "address, size, method_name" information to perf, 38 // and allows perf to map samples in jit-code-cache to jitted method symbols. 39 // 40 // Command line Example: 41 // $ perf record dalvikvm -Xcompiler-option --generate-debug-info -cp <classpath> Test 42 // $ perf report 43 // NOTE: 44 // - Make sure that the perf-PID.map file is available for 'perf report' tool to access, 45 // so that jitted method can be displayed. 46 // 47 // 48 // (2) perf-inject: 49 // The perf-inject mechansim generates jit-PID.dump file, 50 // which provides rich informations about a jitted method. 51 // It allows perf or other profiling tools to do advanced analysis on jitted code, 52 // for example instruction level profiling. 53 // 54 // Command line Example: 55 // $ perf record -k mono dalvikvm -Xcompiler-option --generate-debug-info -cp <classpath> Test 56 // $ perf inject -i perf.data -o perf.data.jitted 57 // $ perf report -i perf.data.jitted 58 // $ perf annotate -i perf.data.jitted 59 // NOTE: 60 // REQUIREMENTS 61 // - The 'perf record -k mono' option requires 4.1 (or higher) Linux kernel. 62 // - The 'perf inject' (generating jit ELF files feature) requires perf 4.6 (or higher). 63 // PERF RECORD 64 // - The '-k mono' option tells 'perf record' to use CLOCK_MONOTONIC clock during sampling; 65 // which is required by 'perf inject', to make sure that both perf.data and jit-PID.dump 66 // have unified clock source for timestamps. 67 // PERF INJECT 68 // - The 'perf inject' tool injects information from jit-PID.dump into perf.data file, 69 // and generates small ELF files (jitted-TID-CODEID.so) for each jitted method. 70 // - On Android devices, the jit-PID.dump file is generated in /data/misc/trace/ folder, and 71 // such location is recorded in perf.data file. 72 // The 'perf inject' tool is going to look for jit-PID.dump and generates small ELF files in 73 // this /data/misc/trace/ folder. 74 // Make sure that you have the read/write access to /data/misc/trace/ folder. 75 // - On non-Android devices, the jit-PID.dump file is generated in /tmp/ folder, and 76 // 'perf inject' tool operates on this folder. 77 // Make sure that you have the read/write access to /tmp/ folder. 78 // - If you are executing 'perf inject' on non-Android devices (host), but perf.data and 79 // jit-PID.dump files are adb-pulled from Android devices, make sure that there is a 80 // /data/misc/trace/ folder on host, and jit-PID.dump file is copied to this folder. 81 // - Currently 'perf inject' doesn't provide option to change the path for jit-PID.dump and 82 // generated ELF files. 83 // PERF ANNOTATE 84 // - The 'perf annotate' tool displays assembly level profiling report. 85 // Source code can also be displayed if the ELF file has debug symbols. 86 // - Make sure above small ELF files are available for 'perf annotate' tool to access, 87 // so that jitted code can be displayed in assembly view. 88 // 89 class JitLogger { 90 public: JitLogger()91 JitLogger() : code_index_(0), marker_address_(nullptr) {} 92 OpenLog()93 void OpenLog() { 94 OpenPerfMapLog(); 95 OpenJitDumpLog(); 96 } 97 WriteLog(const void * ptr,size_t code_size,ArtMethod * method)98 void WriteLog(const void* ptr, size_t code_size, ArtMethod* method) 99 REQUIRES_SHARED(Locks::mutator_lock_) { 100 WritePerfMapLog(ptr, code_size, method); 101 WriteJitDumpLog(ptr, code_size, method); 102 } 103 CloseLog()104 void CloseLog() { 105 ClosePerfMapLog(); 106 CloseJitDumpLog(); 107 } 108 109 private: 110 // For perf-map profiling 111 void OpenPerfMapLog(); 112 void WritePerfMapLog(const void* ptr, size_t code_size, ArtMethod* method) 113 REQUIRES_SHARED(Locks::mutator_lock_); 114 void ClosePerfMapLog(); 115 116 // For perf-inject profiling 117 void OpenJitDumpLog(); 118 void WriteJitDumpLog(const void* ptr, size_t code_size, ArtMethod* method) 119 REQUIRES_SHARED(Locks::mutator_lock_); 120 void CloseJitDumpLog(); 121 122 void OpenMarkerFile(); 123 void CloseMarkerFile(); 124 void WriteJitDumpHeader(); 125 void WriteJitDumpDebugInfo(); 126 127 std::unique_ptr<File> perf_file_; 128 std::unique_ptr<File> jit_dump_file_; 129 uint64_t code_index_; 130 void* marker_address_; 131 132 DISALLOW_COPY_AND_ASSIGN(JitLogger); 133 }; 134 135 } // namespace jit 136 } // namespace art 137 138 #endif // ART_COMPILER_JIT_JIT_LOGGER_H_ 139