1 /* 2 * Copyright (C) 2020 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 #include "src/trace_processor/tp_metatrace.h" 18 19 namespace perfetto { 20 namespace trace_processor { 21 namespace metatrace { 22 23 namespace { 24 25 using ProtoEnum = protos::pbzero::MetatraceCategories; MetatraceCategoriesToProtoEnum(MetatraceCategories categories)26ProtoEnum MetatraceCategoriesToProtoEnum(MetatraceCategories categories) { 27 ProtoEnum result = ProtoEnum::NONE; 28 if (categories & MetatraceCategories::TOPLEVEL) 29 result = static_cast<ProtoEnum>(result | ProtoEnum::TOPLEVEL); 30 if (categories & MetatraceCategories::FUNCTION) 31 result = static_cast<ProtoEnum>(result | ProtoEnum::FUNCTION); 32 if (categories & MetatraceCategories::QUERY) 33 result = static_cast<ProtoEnum>(result | ProtoEnum::QUERY); 34 return result; 35 } 36 37 } // namespace 38 39 Category g_enabled_categories = Category::NONE; 40 Enable(MetatraceConfig config)41void Enable(MetatraceConfig config) { 42 g_enabled_categories = MetatraceCategoriesToProtoEnum(config.categories); 43 if (config.override_buffer_size) { 44 RingBuffer::GetInstance()->Resize(config.override_buffer_size); 45 } 46 } 47 DisableAndReadBuffer(std::function<void (Record *)> fn)48void DisableAndReadBuffer(std::function<void(Record*)> fn) { 49 g_enabled_categories = Category::NONE; 50 if (!fn) 51 return; 52 RingBuffer::GetInstance()->ReadAll(fn); 53 } 54 RingBuffer()55RingBuffer::RingBuffer() : data_(kDefaultCapacity) { 56 static_assert((kDefaultCapacity & (kDefaultCapacity - 1)) == 0, 57 "Capacity should be a power of 2"); 58 } 59 Resize(size_t requested_capacity)60void RingBuffer::Resize(size_t requested_capacity) { 61 size_t actual_capacity = 1; 62 while (actual_capacity < requested_capacity) 63 actual_capacity <<= 1; 64 data_.resize(actual_capacity); 65 start_idx_ = 0; 66 write_idx_ = 0; 67 } 68 ReadAll(std::function<void (Record *)> fn)69void RingBuffer::ReadAll(std::function<void(Record*)> fn) { 70 // Mark as reading so we don't get reentrancy in obtaining new 71 // trace events. 72 is_reading_ = true; 73 74 uint64_t start = (write_idx_ - start_idx_) < data_.size() 75 ? start_idx_ 76 : write_idx_ - data_.size(); 77 uint64_t end = write_idx_; 78 79 // Increment the write index by kCapacity + 1. This ensures that if 80 // ScopedEntry is destoryed in |fn| below, we won't get overwrites 81 // while reading the buffer. 82 // This works because of the logic in ~ScopedEntry and 83 // RingBuffer::HasOverwritten which ensures that we don't overwrite entries 84 // more than kCapcity elements in the past. 85 write_idx_ += data_.size() + 1; 86 87 for (uint64_t i = start; i < end; ++i) { 88 Record* record = At(i); 89 90 // If the slice was unfinished for some reason, don't emit it. 91 if (record->duration_ns != 0) { 92 fn(record); 93 } 94 } 95 96 // Ensure that the start pointer is updated to the write pointer. 97 start_idx_ = write_idx_; 98 99 // Remove the reading marker. 100 is_reading_ = false; 101 } 102 103 } // namespace metatrace 104 } // namespace trace_processor 105 } // namespace perfetto 106