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#ifndef ANDROID_HWUI_TASK_MANAGER_H
18#define ANDROID_HWUI_TASK_MANAGER_H
19
20#include <utils/Mutex.h>
21#include <utils/String8.h>
22#include <utils/Thread.h>
23#include <utils/Vector.h>
24
25#include "Signal.h"
26
27namespace android {
28namespace uirenderer {
29
30template <typename T>
31class Task;
32class TaskBase;
33
34template <typename T>
35class TaskProcessor;
36class TaskProcessorBase;
37
38class TaskManager {
39public:
40    TaskManager();
41    ~TaskManager();
42
43    /**
44     * Returns true if this task  manager can run tasks,
45     * false otherwise. This method will typically return
46     * true on a single CPU core device.
47     */
48    bool canRunTasks() const;
49
50    /**
51     * Stops all allocated threads. Adding tasks will start
52     * the threads again as necessary.
53     */
54    void stop();
55
56private:
57    template <typename T>
58    friend class TaskProcessor;
59
60    template<typename T>
61    bool addTask(const sp<Task<T> >& task, const sp<TaskProcessor<T> >& processor) {
62        return addTaskBase(sp<TaskBase>(task), sp<TaskProcessorBase>(processor));
63    }
64
65    bool addTaskBase(const sp<TaskBase>& task, const sp<TaskProcessorBase>& processor);
66
67    struct TaskWrapper {
68        TaskWrapper(): mTask(), mProcessor() { }
69
70        TaskWrapper(const sp<TaskBase>& task, const sp<TaskProcessorBase>& processor):
71            mTask(task), mProcessor(processor) {
72        }
73
74        sp<TaskBase> mTask;
75        sp<TaskProcessorBase> mProcessor;
76    };
77
78    class WorkerThread: public Thread {
79    public:
80        WorkerThread(const String8 name): mSignal(Condition::WAKE_UP_ONE), mName(name) { }
81
82        bool addTask(TaskWrapper task);
83        size_t getTaskCount() const;
84        void exit();
85
86    private:
87        virtual bool threadLoop();
88
89        // Lock for the list of tasks
90        mutable Mutex mLock;
91        Vector<TaskWrapper> mTasks;
92
93        // Signal used to wake up the thread when a new
94        // task is available in the list
95        mutable Signal mSignal;
96
97        const String8 mName;
98    };
99
100    Vector<sp<WorkerThread> > mThreads;
101};
102
103}; // namespace uirenderer
104}; // namespace android
105
106#endif // ANDROID_HWUI_TASK_MANAGER_H
107