1 /*
2  * Copyright (C) 2012 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 #include <errno.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <unistd.h>
21 
22 #include <string>
23 #include <vector>
24 
25 #include <android-base/file.h>
26 
27 using namespace std::literals;
28 
29 #if defined(__BIONIC__)
30 
31 #define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
32 #include <sys/_system_properties.h>
33 
34 #include <benchmark/benchmark.h>
35 #include <system_properties/system_properties.h>
36 #include "util.h"
37 
38 struct LocalPropertyTestState {
LocalPropertyTestStateLocalPropertyTestState39   explicit LocalPropertyTestState(int nprops)
40       : nprops(nprops), valid(false), system_properties_(false) {
41     static const char prop_name_chars[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-_.";
42 
43     valid = system_properties_.AreaInit(dir_.path, nullptr);
44     if (!valid) {
45       return;
46     }
47 
48     names = new char* [nprops];
49     name_lens = new int[nprops];
50     values = new char* [nprops];
51     value_lens = new int[nprops];
52 
53     srandom(nprops);
54 
55     for (int i = 0; i < nprops; i++) {
56       // Make sure the name has at least 10 characters to make
57       // it very unlikely to generate the same random name.
58       name_lens[i] = (random() % (PROP_NAME_MAX - 10)) + 10;
59       names[i] = new char[PROP_NAME_MAX + 1];
60       size_t prop_name_len = sizeof(prop_name_chars) - 1;
61       for (int j = 0; j < name_lens[i]; j++) {
62         if (j == 0 || names[i][j-1] == '.' || j == name_lens[i] - 1) {
63           // Certain values are not allowed:
64           // - Don't start name with '.'
65           // - Don't allow '.' to appear twice in a row
66           // - Don't allow the name to end with '.'
67           // This assumes that '.' is the last character in the
68           // array so that decrementing the length by one removes
69           // the value from the possible values.
70           prop_name_len--;
71         }
72         names[i][j] = prop_name_chars[random() % prop_name_len];
73       }
74       names[i][name_lens[i]] = 0;
75 
76       // Make sure the value contains at least 1 character.
77       value_lens[i] = (random() % (PROP_VALUE_MAX - 1)) + 1;
78       values[i] = new char[PROP_VALUE_MAX];
79       for (int j = 0; j < value_lens[i]; j++) {
80         values[i][j] = prop_name_chars[random() % (sizeof(prop_name_chars) - 1)];
81       }
82 
83       if (system_properties_.Add(names[i], name_lens[i], values[i], value_lens[i]) < 0) {
84         printf("Failed to add a property, terminating...\n");
85         printf("%s = %.*s\n", names[i], value_lens[i], values[i]);
86         exit(1);
87       }
88     }
89 
90     valid = true;
91   }
92 
system_propertiesLocalPropertyTestState93   SystemProperties& system_properties() {
94     return system_properties_;
95   }
96 
~LocalPropertyTestStateLocalPropertyTestState97   ~LocalPropertyTestState() {
98     if (!valid) {
99       return;
100     }
101 
102     system_properties_.contexts_->FreeAndUnmap();
103 
104     for (int i = 0; i < nprops; i++) {
105       delete names[i];
106       delete values[i];
107     }
108     delete[] names;
109     delete[] name_lens;
110     delete[] values;
111     delete[] value_lens;
112   }
113 
114  public:
115   const int nprops;
116   char** names;
117   int* name_lens;
118   char** values;
119   int* value_lens;
120   bool valid;
121 
122  private:
123   SystemProperties system_properties_;
124   TemporaryDir dir_;
125 };
126 
BM_property_get(benchmark::State & state)127 static void BM_property_get(benchmark::State& state) {
128   const size_t nprops = state.range(0);
129 
130   LocalPropertyTestState pa(nprops);
131   if (!pa.valid) return;
132 
133   while (state.KeepRunning()) {
134     char value[PROP_VALUE_MAX];
135     pa.system_properties().Get(pa.names[random() % nprops], value);
136   }
137 }
138 BIONIC_BENCHMARK_WITH_ARG(BM_property_get, "NUM_PROPS");
139 
BM_property_find(benchmark::State & state)140 static void BM_property_find(benchmark::State& state) {
141   const size_t nprops = state.range(0);
142 
143   LocalPropertyTestState pa(nprops);
144   if (!pa.valid) return;
145 
146   while (state.KeepRunning()) {
147     pa.system_properties().Find(pa.names[random() % nprops]);
148   }
149 }
150 BIONIC_BENCHMARK_WITH_ARG(BM_property_find, "NUM_PROPS");
151 
BM_property_read(benchmark::State & state)152 static void BM_property_read(benchmark::State& state) {
153   const size_t nprops = state.range(0);
154 
155   LocalPropertyTestState pa(nprops);
156   if (!pa.valid) return;
157 
158   const prop_info** pinfo = new const prop_info*[nprops];
159   char propvalue[PROP_VALUE_MAX];
160 
161   for (size_t i = 0; i < nprops; ++i) {
162     pinfo[i] = pa.system_properties().Find(pa.names[random() % nprops]);
163   }
164 
165   size_t i = 0;
166   while (state.KeepRunning()) {
167     pa.system_properties().Read(pinfo[i], nullptr, propvalue);
168     i = (i + 1) % nprops;
169   }
170 
171   delete[] pinfo;
172 }
173 BIONIC_BENCHMARK_WITH_ARG(BM_property_read, "NUM_PROPS");
174 
BM_property_serial(benchmark::State & state)175 static void BM_property_serial(benchmark::State& state) {
176   const size_t nprops = state.range(0);
177 
178   LocalPropertyTestState pa(nprops);
179   if (!pa.valid) return;
180 
181   const prop_info** pinfo = new const prop_info*[nprops];
182   for (size_t i = 0; i < nprops; ++i) {
183     pinfo[i] = pa.system_properties().Find(pa.names[random() % nprops]);
184   }
185 
186   size_t i = 0;
187   while (state.KeepRunning()) {
188     __system_property_serial(pinfo[i]);
189     i = (i + 1) % nprops;
190   }
191 
192   delete[] pinfo;
193 }
194 BIONIC_BENCHMARK_WITH_ARG(BM_property_serial, "NUM_PROPS");
195 
196 // This benchmarks find the actual properties currently set on the system and accessible by the
197 // user that runs this benchmark (aka this is best run as root).  It is not comparable between
198 // devices, nor even boots, but is useful to understand the the real end-to-end speed, including
199 // costs to find the correct property file within /dev/__properties__.
BM_property_find_real(benchmark::State & state)200 static void BM_property_find_real(benchmark::State& state) {
201   std::vector<std::string> properties;
202   __system_property_foreach(
203       [](const prop_info* pi, void* cookie) {
204         __system_property_read_callback(pi,
205                                         [](void* cookie, const char* name, const char*, unsigned) {
206                                           auto properties =
207                                               reinterpret_cast<std::vector<std::string>*>(cookie);
208                                           properties->emplace_back(name);
209                                         },
210                                         cookie);
211       },
212       &properties);
213 
214   while (state.KeepRunning()) {
215     for (const auto& property : properties) {
216       __system_property_find(property.c_str());
217     }
218   }
219 }
220 BIONIC_BENCHMARK(BM_property_find_real);
221 
222 #endif  // __BIONIC__
223