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/sysinfo.h>
18 #if defined(HAVE_PTHREADS)
19 #include <sys/resource.h>
20 #endif
21 
22 #include "TaskManager.h"
23 #include "Task.h"
24 #include "TaskProcessor.h"
25 #include "utils/MathUtils.h"
26 
27 namespace android {
28 namespace uirenderer {
29 
30 ///////////////////////////////////////////////////////////////////////////////
31 // Manager
32 ///////////////////////////////////////////////////////////////////////////////
33 
TaskManager()34 TaskManager::TaskManager() {
35     // Get the number of available CPUs. This value does not change over time.
36     int cpuCount = sysconf(_SC_NPROCESSORS_CONF);
37 
38     int workerCount = MathUtils::max(1, cpuCount / 2);
39     for (int i = 0; i < workerCount; i++) {
40         String8 name;
41         name.appendFormat("hwuiTask%d", i + 1);
42         mThreads.add(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 #if defined(HAVE_PTHREADS)
87     setpriority(PRIO_PROCESS, 0, PRIORITY_FOREGROUND);
88 #endif
89     return NO_ERROR;
90 }
91 
threadLoop()92 bool TaskManager::WorkerThread::threadLoop() {
93     mSignal.wait();
94     Vector<TaskWrapper> tasks;
95     {
96         Mutex::Autolock l(mLock);
97         tasks = mTasks;
98         mTasks.clear();
99     }
100 
101     for (size_t i = 0; i < tasks.size(); i++) {
102         const TaskWrapper& task = tasks.itemAt(i);
103         task.mProcessor->process(task.mTask);
104     }
105 
106     return true;
107 }
108 
addTask(TaskWrapper task)109 bool TaskManager::WorkerThread::addTask(TaskWrapper task) {
110     if (!isRunning()) {
111         run(mName.string(), PRIORITY_DEFAULT);
112     }
113 
114     Mutex::Autolock l(mLock);
115     ssize_t index = mTasks.add(task);
116     mSignal.signal();
117 
118     return index >= 0;
119 }
120 
getTaskCount() const121 size_t TaskManager::WorkerThread::getTaskCount() const {
122     Mutex::Autolock l(mLock);
123     return mTasks.size();
124 }
125 
exit()126 void TaskManager::WorkerThread::exit() {
127     {
128         Mutex::Autolock l(mLock);
129         mTasks.clear();
130     }
131     requestExit();
132     mSignal.signal();
133 }
134 
135 }; // namespace uirenderer
136 }; // namespace android
137