1 /*
2  * Copyright (C) 2015 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 SIMPLE_PERF_RECORD_FILE_H_
18 #define SIMPLE_PERF_RECORD_FILE_H_
19 
20 #include <stdio.h>
21 
22 #include <functional>
23 #include <map>
24 #include <memory>
25 #include <string>
26 #include <unordered_map>
27 #include <vector>
28 
29 #include <android-base/macros.h>
30 
31 #include "dso.h"
32 #include "event_attr.h"
33 #include "perf_event.h"
34 #include "record.h"
35 #include "record_file_format.h"
36 #include "thread_tree.h"
37 
38 // RecordFileWriter writes to a perf record file, like perf.data.
39 class RecordFileWriter {
40  public:
41   static std::unique_ptr<RecordFileWriter> CreateInstance(const std::string& filename);
42 
43   ~RecordFileWriter();
44 
45   bool WriteAttrSection(const std::vector<EventAttrWithId>& attr_ids);
46   bool WriteRecord(const Record& record);
47 
48   bool ReadDataSection(const std::function<void(const Record*)>& callback);
49 
50   bool BeginWriteFeatures(size_t feature_count);
51   bool WriteBuildIdFeature(const std::vector<BuildIdRecord>& build_id_records);
52   bool WriteFeatureString(int feature, const std::string& s);
53   bool WriteCmdlineFeature(const std::vector<std::string>& cmdline);
54   bool WriteBranchStackFeature();
55   bool WriteFileFeature(const std::string& file_path,
56                         uint32_t file_type,
57                         uint64_t min_vaddr,
58                         const std::vector<const Symbol*>& symbols);
59   bool EndWriteFeatures();
60 
61   // Normally, Close() should be called after writing. But if something
62   // wrong happens and we need to finish in advance, the destructor
63   // will take care of calling Close().
64   bool Close();
65 
66  private:
67   RecordFileWriter(const std::string& filename, FILE* fp);
68   void GetHitModulesInBuffer(const char* p, const char* end,
69                              std::vector<std::string>* hit_kernel_modules,
70                              std::vector<std::string>* hit_user_files);
71   bool WriteFileHeader();
72   bool WriteData(const void* buf, size_t len);
73   bool Write(const void* buf, size_t len);
74   bool Read(void* buf, size_t len);
75   bool GetFilePos(uint64_t* file_pos);
76   bool WriteStringWithLength(const std::string& s);
77   bool WriteFeatureBegin(int feature);
78   bool WriteFeatureEnd(int feature);
79 
80   const std::string filename_;
81   FILE* record_fp_;
82 
83   perf_event_attr event_attr_;
84   uint64_t attr_section_offset_;
85   uint64_t attr_section_size_;
86   uint64_t data_section_offset_;
87   uint64_t data_section_size_;
88   uint64_t feature_section_offset_;
89 
90   std::map<int, PerfFileFormat::SectionDesc> features_;
91   size_t feature_count_;
92 
93   DISALLOW_COPY_AND_ASSIGN(RecordFileWriter);
94 };
95 
96 // RecordFileReader read contents from a perf record file, like perf.data.
97 class RecordFileReader {
98  public:
99   static std::unique_ptr<RecordFileReader> CreateInstance(const std::string& filename);
100 
101   ~RecordFileReader();
102 
FileHeader()103   const PerfFileFormat::FileHeader& FileHeader() const {
104     return header_;
105   }
106 
AttrSection()107   std::vector<EventAttrWithId> AttrSection() const {
108     std::vector<EventAttrWithId> result(file_attrs_.size());
109     for (size_t i = 0; i < file_attrs_.size(); ++i) {
110       result[i].attr = &file_attrs_[i].attr;
111       result[i].ids = event_ids_for_file_attrs_[i];
112     }
113     return result;
114   }
115 
FeatureSectionDescriptors()116   const std::map<int, PerfFileFormat::SectionDesc>& FeatureSectionDescriptors() const {
117     return feature_section_descriptors_;
118   }
HasFeature(int feature)119   bool HasFeature(int feature) const {
120     return feature_section_descriptors_.find(feature) != feature_section_descriptors_.end();
121   }
122   bool ReadFeatureSection(int feature, std::vector<char>* data);
123 
124   // There are two ways to read records in data section: one is by calling
125   // ReadDataSection(), and [callback] is called for each Record. the other
126   // is by calling ReadRecord() in a loop.
127 
128   // If sorted is true, sort records before passing them to callback function.
129   bool ReadDataSection(const std::function<bool(std::unique_ptr<Record>)>& callback,
130                        bool sorted = true);
131 
132   // Read next record. If read successfully, set [record] and return true.
133   // If there is no more records, set [record] to nullptr and return true.
134   // Otherwise return false.
135   bool ReadRecord(std::unique_ptr<Record>& record, bool sorted = true);
136 
137   size_t GetAttrIndexOfRecord(const Record* record);
138 
139   std::vector<std::string> ReadCmdlineFeature();
140   std::vector<BuildIdRecord> ReadBuildIdFeature();
141   std::string ReadFeatureString(int feature);
142 
143   // File feature section contains many file information. This function reads
144   // one file information located at [read_pos]. [read_pos] is 0 at the first
145   // call, and is updated to point to the next file information. Return true
146   // if read successfully, and return false if there is no more file
147   // information.
148   bool ReadFileFeature(size_t& read_pos, std::string* file_path,
149                        uint32_t* file_type, uint64_t* min_vaddr,
150                        std::vector<Symbol>* symbols);
151 
152   void LoadBuildIdAndFileFeatures(ThreadTree& thread_tree);
153 
154   bool Close();
155 
156   // For testing only.
157   std::vector<std::unique_ptr<Record>> DataSection();
158 
159  private:
160   RecordFileReader(const std::string& filename, FILE* fp);
161   bool ReadHeader();
162   bool ReadAttrSection();
163   bool ReadIdsForAttr(const PerfFileFormat::FileAttr& attr, std::vector<uint64_t>* ids);
164   bool ReadFeatureSectionDescriptors();
165   std::unique_ptr<Record> ReadRecord(uint64_t* nbytes_read);
166   bool Read(void* buf, size_t len);
167   void ProcessEventIdRecord(const EventIdRecord& r);
168 
169   const std::string filename_;
170   FILE* record_fp_;
171 
172   PerfFileFormat::FileHeader header_;
173   std::vector<PerfFileFormat::FileAttr> file_attrs_;
174   std::vector<std::vector<uint64_t>> event_ids_for_file_attrs_;
175   std::unordered_map<uint64_t, size_t> event_id_to_attr_map_;
176   std::map<int, PerfFileFormat::SectionDesc> feature_section_descriptors_;
177 
178   size_t event_id_pos_in_sample_records_;
179   size_t event_id_reverse_pos_in_non_sample_records_;
180 
181   std::unique_ptr<RecordCache> record_cache_;
182   uint64_t read_record_size_;
183 
184   DISALLOW_COPY_AND_ASSIGN(RecordFileReader);
185 };
186 
187 #endif  // SIMPLE_PERF_RECORD_FILE_H_
188