1 /*
2  * Copyright (C) 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 #include <sys/resource.h>
18 #include <sys/sysinfo.h>
19 
20 #include "TaskManager.h"
21 #include "Task.h"
22 #include "TaskProcessor.h"
23 #include "utils/MathUtils.h"
24 
25 namespace android {
26 namespace uirenderer {
27 
28 ///////////////////////////////////////////////////////////////////////////////
29 // Manager
30 ///////////////////////////////////////////////////////////////////////////////
31 
TaskManager()32 TaskManager::TaskManager() {
33     // Get the number of available CPUs. This value does not change over time.
34     int cpuCount = sysconf(_SC_NPROCESSORS_CONF);
35 
36     // Really no point in making more than 2 of these worker threads, but
37     // we do want to limit ourselves to 1 worker thread on dual-core devices.
38     int workerCount = cpuCount > 2 ? 2 : 1;
39     for (int i = 0; i < workerCount; i++) {
40         String8 name;
41         name.appendFormat("hwuiTask%d", i + 1);
42         mThreads.push_back(new WorkerThread(name));
43     }
44 }
45 
~TaskManager()46 TaskManager::~TaskManager() {
47     for (size_t i = 0; i < mThreads.size(); i++) {
48         mThreads[i]->exit();
49     }
50 }
51 
canRunTasks() const52 bool TaskManager::canRunTasks() const {
53     return mThreads.size() > 0;
54 }
55 
stop()56 void TaskManager::stop() {
57     for (size_t i = 0; i < mThreads.size(); i++) {
58         mThreads[i]->exit();
59     }
60 }
61 
addTaskBase(const sp<TaskBase> & task,const sp<TaskProcessorBase> & processor)62 bool TaskManager::addTaskBase(const sp<TaskBase>& task, const sp<TaskProcessorBase>& processor) {
63     if (mThreads.size() > 0) {
64         TaskWrapper wrapper(task, processor);
65 
66         size_t minQueueSize = INT_MAX;
67         sp<WorkerThread> thread;
68 
69         for (size_t i = 0; i < mThreads.size(); i++) {
70             if (mThreads[i]->getTaskCount() < minQueueSize) {
71                 thread = mThreads[i];
72                 minQueueSize = mThreads[i]->getTaskCount();
73             }
74         }
75 
76         return thread->addTask(wrapper);
77     }
78     return false;
79 }
80 
81 ///////////////////////////////////////////////////////////////////////////////
82 // Thread
83 ///////////////////////////////////////////////////////////////////////////////
84 
readyToRun()85 status_t TaskManager::WorkerThread::readyToRun() {
86     setpriority(PRIO_PROCESS, 0, PRIORITY_FOREGROUND);
87     return NO_ERROR;
88 }
89 
threadLoop()90 bool TaskManager::WorkerThread::threadLoop() {
91     mSignal.wait();
92     std::vector<TaskWrapper> tasks;
93     {
94         Mutex::Autolock l(mLock);
95         tasks.swap(mTasks);
96     }
97 
98     for (size_t i = 0; i < tasks.size(); i++) {
99         const TaskWrapper& task = tasks[i];
100         task.mProcessor->process(task.mTask);
101     }
102 
103     return true;
104 }
105 
addTask(const TaskWrapper & task)106 bool TaskManager::WorkerThread::addTask(const TaskWrapper& task) {
107     if (!isRunning()) {
108         run(mName.string(), PRIORITY_DEFAULT);
109     } else if (exitPending()) {
110         return false;
111     }
112 
113     {
114         Mutex::Autolock l(mLock);
115         mTasks.push_back(task);
116     }
117     mSignal.signal();
118 
119     return true;
120 }
121 
getTaskCount() const122 size_t TaskManager::WorkerThread::getTaskCount() const {
123     Mutex::Autolock l(mLock);
124     return mTasks.size();
125 }
126 
exit()127 void TaskManager::WorkerThread::exit() {
128     requestExit();
129     mSignal.signal();
130 }
131 
132 }; // namespace uirenderer
133 }; // namespace android
134