1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
/*
* Copyright (C) 2021 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "powerhal-adaptivecpu"
#define ATRACE_TAG (ATRACE_TAG_POWER | ATRACE_TAG_HAL)
#include "CpuLoadReaderSysDevices.h"
#include <android-base/logging.h>
#include <inttypes.h>
#include <utils/Trace.h>
#include <fstream>
#include <sstream>
#include <string>
namespace aidl {
namespace google {
namespace hardware {
namespace power {
namespace impl {
namespace pixel {
std::chrono::nanoseconds getKernelTime() {
timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return std::chrono::nanoseconds(ts.tv_sec * 1000000000UL + ts.tv_nsec);
}
bool CpuLoadReaderSysDevices::Init() {
mIdleStateNames.clear();
if (!ReadIdleStateNames(&mIdleStateNames)) {
return false;
}
return ReadCpuTimes(&mPreviousCpuTimes);
}
bool CpuLoadReaderSysDevices::GetRecentCpuLoads(
std::array<double, NUM_CPU_CORES> *cpuCoreIdleTimesPercentage) {
ATRACE_CALL();
if (cpuCoreIdleTimesPercentage == nullptr) {
LOG(ERROR) << "Got nullptr output in getRecentCpuLoads";
return false;
}
std::array<CpuTime, NUM_CPU_CORES> cpuTimes;
if (!ReadCpuTimes(&cpuTimes)) {
return false;
}
if (cpuTimes.empty()) {
LOG(ERROR) << "Failed to find any CPU times";
return false;
}
for (size_t cpuId = 0; cpuId < NUM_CPU_CORES; cpuId++) {
const auto cpuTime = cpuTimes[cpuId];
const auto previousCpuTime = mPreviousCpuTimes[cpuId];
auto recentIdleTime = cpuTime.idleTime - previousCpuTime.idleTime;
const auto recentTotalTime = cpuTime.totalTime - previousCpuTime.totalTime;
if (recentIdleTime > recentTotalTime) {
// This happens occasionally, as we use the idle time from the kernel, and the current
// time from userspace.
recentIdleTime = recentTotalTime;
}
const double idleTimePercentage =
static_cast<double>(recentIdleTime.count()) / recentTotalTime.count();
(*cpuCoreIdleTimesPercentage)[cpuId] = idleTimePercentage;
}
mPreviousCpuTimes = cpuTimes;
return true;
}
void CpuLoadReaderSysDevices::DumpToStream(std::stringstream &stream) const {
stream << "CPU loads from /sys/devices/system/cpu/cpuN/cpuidle:\n";
for (size_t cpuId = 0; cpuId < NUM_CPU_CORES; cpuId++) {
stream << "- CPU=" << cpuId << ", idleTime=" << mPreviousCpuTimes[cpuId].idleTime.count()
<< "ms, totalTime=" << mPreviousCpuTimes[cpuId].totalTime.count() << "ms\n";
}
}
bool CpuLoadReaderSysDevices::ReadCpuTimes(std::array<CpuTime, NUM_CPU_CORES> *result) const {
ATRACE_CALL();
const auto totalTime = mTimeSource->GetTime();
for (size_t cpuId = 0; cpuId < NUM_CPU_CORES; cpuId++) {
std::chrono::microseconds idleTime;
for (const auto &idleStateName : mIdleStateNames) {
std::stringstream cpuIdlePath;
cpuIdlePath << "/sys/devices/system/cpu/"
<< "cpu" << cpuId << "/cpuidle/" << idleStateName << "/time";
std::unique_ptr<std::istream> file;
if (!mFilesystem->ReadFileStream(cpuIdlePath.str(), &file)) {
return false;
}
// Times are reported in microseconds:
// https://www.kernel.org/doc/Documentation/cpuidle/sysfs.txt
std::string idleTimeUs(std::istreambuf_iterator<char>(*file), {});
idleTime += std::chrono::microseconds(std::atoi(idleTimeUs.c_str()));
}
(*result)[cpuId] = {
.idleTime = idleTime,
.totalTime = std::chrono::duration_cast<std::chrono::microseconds>(totalTime),
};
}
return true;
}
bool CpuLoadReaderSysDevices::ReadIdleStateNames(std::vector<std::string> *result) const {
std::vector<std::string> idleStateNames;
if (!mFilesystem->ListDirectory("/sys/devices/system/cpu/cpu0/cpuidle", &idleStateNames)) {
return false;
}
for (const auto &idleStateName : idleStateNames) {
if (idleStateName.length() == 0 || idleStateName[0] == '.') {
continue;
}
std::vector<std::string> files;
if (!mFilesystem->ListDirectory(
std::string("/sys/devices/system/cpu/cpu0/cpuidle/") + idleStateName, &files)) {
return false;
}
if (std::find(files.begin(), files.end(), "time") == files.end()) {
continue;
}
result->push_back(idleStateName);
}
if (idleStateNames.empty()) {
LOG(ERROR) << "Found no idle state names";
return false;
}
return true;
}
} // namespace pixel
} // namespace impl
} // namespace power
} // namespace hardware
} // namespace google
} // namespace aidl
|
