1 /* 2 * Copyright (C) 2018 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 #pragma once 18 19 #include <sys/types.h> 20 21 #include <string> 22 #include <vector> 23 24 #include "meminfo.h" 25 26 namespace android { 27 namespace meminfo { 28 29 using VmaCallback = std::function<void(const Vma&)>; 30 31 class ProcMemInfo final { 32 // Per-process memory accounting 33 public: 34 // Reset the working set accounting of the process via /proc/<pid>/clear_refs 35 static bool ResetWorkingSet(pid_t pid); 36 37 ProcMemInfo(pid_t pid, bool get_wss = false, uint64_t pgflags = 0, uint64_t pgflags_mask = 0); 38 39 const std::vector<Vma>& Maps(); 40 const MemUsage& Usage(); 41 const MemUsage& Wss(); 42 43 // Same as Maps() except, only valid for reading working set using CONFIG_IDLE_PAGE_TRACKING 44 // support in kernel. If the kernel support doesn't exist, the function will return an empty 45 // vector. 46 const std::vector<Vma>& MapsWithPageIdle(); 47 48 // Collect all 'vma' or 'maps' from /proc/<pid>/smaps and store them in 'maps_'. Returns a 49 // constant reference to the vma vector after the collection is done. 50 // 51 // Each 'struct Vma' is *fully* populated by this method (unlike SmapsOrRollup). 52 const std::vector<Vma>& Smaps(const std::string& path = ""); 53 54 // This method reads /proc/<pid>/smaps and calls the callback() for each 55 // vma or map that it finds. The map is converted to 'struct Vma' object which is then 56 // passed to the callback. 57 // Returns 'false' if the file is malformed. 58 bool ForEachVma(const VmaCallback& callback); 59 60 // Used to parse either of /proc/<pid>/{smaps, smaps_rollup} and record the process's 61 // Pss and Private memory usage in 'stats'. In particular, the method only populates the fields 62 // of the MemUsage structure that are intended to be used by Android's periodic Pss collection. 63 // 64 // The method populates the following statistics in order to be fast an efficient. 65 // Pss 66 // Rss 67 // Uss 68 // private_clean 69 // private_dirty 70 // SwapPss 71 // All other fields of MemUsage are zeroed. 72 bool SmapsOrRollup(MemUsage* stats) const; 73 74 // Used to parse either of /proc/<pid>/{smaps, smaps_rollup} and record the process's 75 // Pss. 76 // Returns 'true' on success and the value of Pss in the out parameter. 77 bool SmapsOrRollupPss(uint64_t* pss) const; 78 79 const std::vector<uint16_t>& SwapOffsets(); 80 81 // Reads /proc/<pid>/pagemap for this process for each page within 82 // the 'vma' and stores that in 'pagemap'. It is assumed that the 'vma' 83 // is obtained by calling Maps() or 'ForEachVma' for the same object. No special checks 84 // are made to see if 'vma' is *valid*. 85 // Returns false if anything goes wrong, 'true' otherwise. 86 bool PageMap(const Vma& vma, std::vector<uint64_t>* pagemap); 87 88 ~ProcMemInfo() = default; 89 90 private: 91 bool ReadMaps(bool get_wss, bool use_pageidle = false); 92 bool ReadVmaStats(int pagemap_fd, Vma& vma, bool get_wss, bool use_pageidle); 93 94 pid_t pid_; 95 bool get_wss_; 96 uint64_t pgflags_; 97 uint64_t pgflags_mask_; 98 99 std::vector<Vma> maps_; 100 101 MemUsage usage_; 102 std::vector<uint16_t> swap_offsets_; 103 }; 104 105 // Makes callback for each 'vma' or 'map' found in file provided. The file is expected to be in the 106 // same format as /proc/<pid>/smaps. Returns 'false' if the file is malformed. 107 bool ForEachVmaFromFile(const std::string& path, const VmaCallback& callback); 108 109 // Returns if the kernel supports /proc/<pid>/smaps_rollup. Assumes that the 110 // calling process has access to the /proc/<pid>/smaps_rollup. 111 // Returns 'false' if the calling process has no permission to read the file if it exists 112 // of if the file doesn't exist. 113 bool IsSmapsRollupSupported(pid_t pid); 114 115 // Same as ProcMemInfo::SmapsOrRollup but reads the statistics directly 116 // from a file. The file MUST be in the same format as /proc/<pid>/smaps 117 // or /proc/<pid>/smaps_rollup 118 bool SmapsOrRollupFromFile(const std::string& path, MemUsage* stats); 119 120 // Same as ProcMemInfo::SmapsOrRollupPss but reads the statistics directly 121 // from a file and returns total Pss in kB. The file MUST be in the same format 122 // as /proc/<pid>/smaps or /proc/<pid>/smaps_rollup 123 bool SmapsOrRollupPssFromFile(const std::string& path, uint64_t* pss); 124 125 } // namespace meminfo 126 } // namespace android 127