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 #ifndef SRC_TRACED_PROBES_COMMON_CPU_FREQ_INFO_H_
18 #define SRC_TRACED_PROBES_COMMON_CPU_FREQ_INFO_H_
19 
20 #include <map>
21 #include <string>
22 #include <vector>
23 
24 #include "perfetto/ext/base/scoped_file.h"
25 
26 namespace perfetto {
27 
28 class CpuFreqInfo {
29  public:
30   explicit CpuFreqInfo(std::string cpu_dir_path = "/sys/devices/system/cpu");
31   virtual ~CpuFreqInfo();
32 
33   using Range =
34       std::pair</* begin */ const uint32_t*, /* end */ const uint32_t*>;
35   Range GetFreqs(uint32_t cpu);
36   uint32_t GetCpuFreqIndex(uint32_t cpu, uint32_t freq);
37 
38  private:
39   // All frequencies of all CPUs, ordered by CPU and frequency. Includes a guard
40   // at the end.
41   std::vector<uint32_t> frequencies_;
42   // frequencies_index_[cpu] points to first frequency in frequencies_. Includes
43   // a guard at the end.
44   std::vector<size_t> frequencies_index_;
45 
46   std::string ReadFile(std::string path);
47 };
48 
49 }  // namespace perfetto
50 
51 #endif  // SRC_TRACED_PROBES_COMMON_CPU_FREQ_INFO_H_
52