1 /*
2  * Copyright 2013 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 __MEMTRACK_H__
18 #define __MEMTRACK_H__
19 
20 #include <sys/types.h>
21 
22 #include <map>
23 #include <string>
24 #include <vector>
25 
26 #define DEFAULT_SLEEP_DELAY_SECONDS 5
27 #ifndef NS_PER_SEC
28 #define NS_PER_SEC 1000000000ULL
29 #endif
30 
31 class FileData {
32 public:
33   FileData(char *filename, char *buffer, size_t buffer_len);
34   ~FileData();
35 
36   // Get the PSS information from the file data. If there are no more
37   // PSS values to be found, return false.
38   bool getPss(size_t *pss);
39 
40   // Check if there is at least bytes available in the file data.
41   bool isAvail(size_t bytes);
42 
43 private:
44   int fd_;
45   char *data_;
46   size_t max_;
47   size_t cur_idx_;
48   size_t len_;
49   bool read_complete_;
50 };
51 
52 typedef struct {
53   std::string name;
54 
55   size_t max_num_pids;
56 
57   size_t num_samples;
58   double avg_pss_kb;
59   size_t min_pss_kb;
60   size_t max_pss_kb;
61   size_t last_pss_kb;
62 
63   std::vector<int> pids;
64 } process_info_t;
65 typedef std::map<std::string, process_info_t> processes_t;
66 
67 typedef struct {
68   size_t pss_kb;
69 
70   std::vector<int> pids;
71 } cur_process_info_t;
72 typedef std::map<std::string, cur_process_info_t> cur_processes_t;
73 
74 class ProcessInfo {
75 public:
76   ProcessInfo();
77   ~ProcessInfo();
78 
79   // Get the information about a single process.
80   bool getInformation(int pid, char *pid_str, size_t pid_str_len);
81 
82   // Scan all of the running processes.
83   void scan();
84 
85   // Dump the information about all of the processes in the system to the log.
86   void dumpToLog();
87 
88 private:
89   static const size_t kBufferLen = 4096;
90   static const size_t kCmdNameLen = 1024;
91 
92   static const char *kProc;
93   static const size_t kProcLen = 6;
94 
95   static const char *kCmdline;
96   static const size_t kCmdlineLen = 9;  // Includes \0 at end of string.
97 
98   static const char *kSmaps;
99   static const size_t kSmapsLen = 7;  // Includes \0 at end of string.
100 
101   static const char *kStatus;
102   static const size_t kStatusLen = 8;  // Includes \0 at end of string.
103 
104   static const size_t kInitialEntries = 1000;
105 
106   char proc_file_[PATH_MAX];
107   char buffer_[kBufferLen];
108 
109   char cmd_name_[kCmdNameLen];
110 
111   // Minimize a need for a lot of allocations by keeping our maps and
112   // lists in this object.
113   processes_t all_;
114   cur_processes_t cur_;
115   std::vector<const process_info_t *> list_;
116 
117   // Compute a running average.
computeAvg(double * running_avg,size_t cur_avg,size_t num_samples)118   static inline void computeAvg(double *running_avg, size_t cur_avg,
119                                 size_t num_samples) {
120     *running_avg = (*running_avg/(num_samples+1))*num_samples
121                    + (double)cur_avg/(num_samples+1);
122   }
123 };
124 
125 #endif  // __MEMTRACK_H__
126