1 // Copyright 2017 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "procfs_utils.h"
6
7 #include <stdio.h>
8 #include <string.h>
9
10 #include "file_utils.h"
11 #include "logging.h"
12
13 using file_utils::ForEachPidInProcPath;
14 using file_utils::ReadProcFile;
15 using file_utils::ReadProcFileTrimmed;
16
17 namespace procfs_utils {
18
19 namespace {
20
21 const char kJavaAppPrefix[] = "/system/bin/app_process";
22 const char kZygotePrefix[] = "zygote";
23
ReadProcString(int pid,const char * path,char * buf,size_t size)24 inline void ReadProcString(int pid, const char* path, char* buf, size_t size) {
25 if (!file_utils::ReadProcFileTrimmed(pid, path, buf, size))
26 buf[0] = '\0';
27 }
28
ReadExePath(int pid,char * buf,size_t size)29 inline void ReadExePath(int pid, char* buf, size_t size) {
30 char exe_path[64];
31 sprintf(exe_path, "/proc/%d/exe", pid);
32 ssize_t res = readlink(exe_path, buf, size - 1);
33 if (res >= 0)
34 buf[res] = '\0';
35 else
36 buf[0] = '\0';
37 }
38
IsApp(const char * name,const char * exe)39 inline bool IsApp(const char* name, const char* exe) {
40 return strncmp(exe, kJavaAppPrefix, sizeof(kJavaAppPrefix) - 1) == 0 &&
41 strncmp(name, kZygotePrefix, sizeof(kZygotePrefix) - 1) != 0;
42 }
43
44 } // namespace
45
ReadTgid(int pid)46 int ReadTgid(int pid) {
47 static const char kTgid[] = "\nTgid:";
48 char buf[512];
49 ssize_t rsize = ReadProcFile(pid, "status", buf, sizeof(buf));
50 if (rsize <= 0)
51 return -1;
52 const char* tgid_line = strstr(buf, kTgid);
53 CHECK(tgid_line);
54 return atoi(tgid_line + sizeof(kTgid) - 1);
55 }
56
ReadProcessInfo(int pid)57 std::unique_ptr<ProcessInfo> ReadProcessInfo(int pid) {
58 ProcessInfo* process = new ProcessInfo();
59 process->pid = pid;
60 ReadProcString(pid, "cmdline", process->name, sizeof(process->name));
61 if (process->name[0] != 0) {
62 ReadExePath(pid, process->exe, sizeof(process->exe));
63 process->is_app = IsApp(process->name, process->exe);
64 } else {
65 ReadProcString(pid, "comm", process->name, sizeof(process->name));
66 CHECK(process->name[0]);
67 process->in_kernel = true;
68 }
69 return std::unique_ptr<ProcessInfo>(process);
70 }
71
ReadProcessThreads(ProcessInfo * process)72 void ReadProcessThreads(ProcessInfo* process) {
73 if (process->in_kernel)
74 return;
75
76 char tasks_path[64];
77 sprintf(tasks_path, "/proc/%d/task", process->pid);
78 ForEachPidInProcPath(tasks_path, [process](int tid) {
79 if (process->threads.count(tid))
80 return;
81 ThreadInfo thread = { tid, "" };
82 char task_comm[64];
83 sprintf(task_comm, "task/%d/comm", tid);
84 ReadProcString(process->pid, task_comm, thread.name, sizeof(thread.name));
85 if (thread.name[0] == '\0' && process->is_app)
86 strcpy(thread.name, "UI Thread");
87 process->threads[tid] = thread;
88 });
89 }
90
ReadOomStats(ProcessSnapshot * snapshot)91 bool ReadOomStats(ProcessSnapshot* snapshot) {
92 char buf[64];
93 if (ReadProcFileTrimmed(snapshot->pid, "oom_score", buf, sizeof(buf)))
94 snapshot->oom_score = atoi(buf);
95 else
96 return false;
97 if (ReadProcFileTrimmed(snapshot->pid, "oom_score_adj", buf, sizeof(buf)))
98 snapshot->oom_score_adj = atoi(buf);
99 else
100 return false;
101 return true;
102 }
103
ReadPageFaultsAndCpuTimeStats(ProcessSnapshot * snapshot)104 bool ReadPageFaultsAndCpuTimeStats(ProcessSnapshot* snapshot) {
105 char buf[512];
106 if (!ReadProcFileTrimmed(snapshot->pid, "stat", buf, sizeof(buf)))
107 return false;
108 int ret = sscanf(buf,
109 "%*d (%*[^)]) %*c %*d %*d %*d %*d %*d %*u %lu %*lu %lu %*lu %lu %lu",
110 &snapshot->minor_faults, &snapshot->major_faults,
111 &snapshot->utime, &snapshot->stime);
112 CHECK(ret == 4);
113 return true;
114 }
115
ReadMemInfoStats(std::map<std::string,uint64_t> * mem_info)116 bool ReadMemInfoStats(std::map<std::string, uint64_t>* mem_info) {
117 char buf[1024];
118 ssize_t rsize = file_utils::ReadFile("/proc/meminfo", buf, sizeof(buf));
119 if (rsize <= 0)
120 return false;
121
122 file_utils::LineReader reader(buf, rsize);
123 for (const char* line = reader.NextLine();
124 line && line[0];
125 line = reader.NextLine()) {
126
127 const char* pos_colon = strstr(line, ":");
128 if (pos_colon == nullptr)
129 continue; // Should not happen.
130 std::string name(line, pos_colon - line);
131 (*mem_info)[name] = strtoull(&pos_colon[1], nullptr, 10);
132 }
133 return true;
134 }
135
136 } // namespace procfs_utils
137