1 /*
2 **
3 ** Copyright 2015, The Android Open Source Project
4 **
5 ** Licensed under the Apache License, Version 2.0 (the "License");
6 ** you may not use this file except in compliance with the License.
7 ** You may obtain a copy of the License at
8 **
9 ** http://www.apache.org/licenses/LICENSE-2.0
10 **
11 ** Unless required by applicable law or agreed to in writing, software
12 ** distributed under the License is distributed on an "AS IS" BASIS,
13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 ** See the License for the specific language governing permissions and
15 ** limitations under the License.
16 */
17
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <unistd.h>
22 #include <string>
23 #include <sstream>
24 #include <sys/types.h>
25 #include <sys/wait.h>
26
27 #include <cutils/properties.h>
28
29 #include "cpuconfig.h"
30 #include "perfprofdutils.h"
31
32 #define SYSFSCPU "/sys/devices/system/cpu"
33
HardwireCpuHelper(bool perform)34 HardwireCpuHelper::HardwireCpuHelper(bool perform)
35 : mpdecision_stopped_(false)
36 {
37 if (perform && GetMpdecisionRunning()) {
38 mpdecision_stopped_ = true;
39 StopMpdecision();
40 int ncores = GetNumCores();
41 for (int i = 0; i < ncores; ++i) {
42 OnlineCore(i, 1);
43 }
44 }
45 }
46
~HardwireCpuHelper()47 HardwireCpuHelper::~HardwireCpuHelper()
48 {
49 if (mpdecision_stopped_) {
50 RestartMpdecision();
51 }
52 }
53
GetMpdecisionRunning()54 bool HardwireCpuHelper::GetMpdecisionRunning()
55 {
56 char propBuf[PROPERTY_VALUE_MAX];
57 property_get("init.svc.mpdecision", propBuf, "");
58 return strcmp(propBuf, "running") == 0;
59 }
60
61
GetNumCores()62 int HardwireCpuHelper::GetNumCores()
63 {
64 int ncores = -1;
65 std::string possible(SYSFSCPU "/possible");
66 FILE *fp = fopen(possible.c_str(), "re");
67 if (fp) {
68 unsigned lo = 0, hi = 0;
69 if (fscanf(fp, "%u-%u", &lo, &hi) == 2) {
70 ncores = hi - lo + 1;
71 }
72 fclose(fp);
73 }
74 return ncores;
75 }
76
OnlineCore(int i,int onoff)77 void HardwireCpuHelper::OnlineCore(int i, int onoff)
78 {
79 std::stringstream ss;
80 ss << SYSFSCPU "/cpu" << i << "/online";
81 FILE *fp = fopen(ss.str().c_str(), "we");
82 if (fp) {
83 fprintf(fp, onoff ? "1\n" : "0\n");
84 fclose(fp);
85 } else {
86 W_ALOGW("open failed for %s", ss.str().c_str());
87 }
88 }
89
StopMpdecision()90 void HardwireCpuHelper::StopMpdecision()
91 {
92 if (property_set("ctl.stop", "mpdecision")) {
93 W_ALOGE("setprop ctl.stop mpdecision failed");
94 }
95 }
96
RestartMpdecision()97 void HardwireCpuHelper::RestartMpdecision()
98 {
99 // Don't try to offline the cores we previously onlined -- let
100 // mpdecision figure out what to do
101
102 if (property_set("ctl.start", "mpdecision")) {
103 W_ALOGE("setprop ctl.start mpdecision failed");
104 }
105 }
106