summaryrefslogtreecommitdiff
path: root/indra/llcommon/llworkerthread.h
blob: 803fff78d9773eb28faba9f5771533ad269c999a (plain)
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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
/**
 * @file llworkerthread.h
 *
 * $LicenseInfo:firstyear=2004&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_LLWORKERTHREAD_H
#define LL_LLWORKERTHREAD_H

#include <list>
#include <map>
#include <queue>
#include <set>
#include <string>

#include "llqueuedthread.h"
#include "llatomic.h"
#include "llmutex.h"

#define USE_FRAME_CALLBACK_MANAGER 0

//============================================================================

class LLWorkerClass;

//============================================================================
// Note: ~LLWorkerThread is O(N) N=# of worker threads, assumed to be small
//   It is assumed that LLWorkerThreads are rarely created/destroyed.

class LL_COMMON_API LLWorkerThread : public LLQueuedThread
{
    friend class LLWorkerClass;
public:
    class WorkRequest : public LLQueuedThread::QueuedRequest
    {
    protected:
        virtual ~WorkRequest(); // use deleteRequest()

    public:
        WorkRequest(handle_t handle, LLWorkerClass* workerclass, S32 param);

        S32 getParam()
        {
            return mParam;
        }
        LLWorkerClass* getWorkerClass()
        {
            return mWorkerClass;
        }

        /*virtual*/ bool processRequest();
        /*virtual*/ void finishRequest(bool completed);
        /*virtual*/ void deleteRequest();

    private:
        LLWorkerClass* mWorkerClass;
        S32 mParam;
    };

protected:
    void clearDeleteList() ;

private:
    typedef std::list<LLWorkerClass*> delete_list_t;
    delete_list_t mDeleteList;
    LLMutex* mDeleteMutex;

public:
    LLWorkerThread(const std::string& name, bool threaded = true, bool should_pause = false);
    ~LLWorkerThread();

    /*virtual*/ size_t update(F32 max_time_ms);

    handle_t addWorkRequest(LLWorkerClass* workerclass, S32 param);

    S32 getNumDeletes() { return (S32)mDeleteList.size(); } // debug

private:
    void deleteWorker(LLWorkerClass* workerclass); // schedule for deletion

};

//============================================================================

// This is a base class which any class with worker functions should derive from.
// Example Usage:
//  LLMyWorkerClass* foo = new LLMyWorkerClass();
//  foo->fetchData(); // calls addWork()
//  while(1) // main loop
//  {
//     if (foo->hasData()) // calls checkWork()
//        foo->processData();
//  }
//
// WorkerClasses only have one set of work functions. If they need to do multiple
//  background tasks, use 'param' to switch amnong them.
// Only one background task can be active at a time (per instance).
//  i.e. don't call addWork() if haveWork() returns true

class LL_COMMON_API LLWorkerClass
{
    friend class LLWorkerThread;
    friend class LLWorkerThread::WorkRequest;

public:
    typedef LLWorkerThread::handle_t handle_t;
    enum FLAGS
    {
        WCF_HAVE_WORK = 0x01,
        WCF_WORKING = 0x02,
        WCF_WORK_FINISHED = 0x10,
        WCF_WORK_ABORTED = 0x20,
        WCF_DELETE_REQUESTED = 0x40,
        WCF_ABORT_REQUESTED = 0x80
    };

public:
    LLWorkerClass(LLWorkerThread* workerthread, const std::string& name);
    virtual ~LLWorkerClass();

    // pure virtual, called from WORKER THREAD, returns true if done
    virtual bool doWork(S32 param)=0; // Called from WorkRequest::processRequest()
    // virtual, called from finishRequest() after completed or aborted
    virtual void finishWork(S32 param, bool completed); // called from finishRequest() (WORK THREAD)
    // virtual, returns true if safe to delete the worker
    virtual bool deleteOK(); // called from update() (WORK THREAD)

    // schedlueDelete(): schedules deletion once aborted or completed
    void scheduleDelete();

    bool haveWork() { return getFlags(WCF_HAVE_WORK); } // may still be true if aborted
    bool isWorking() { return getFlags(WCF_WORKING); }
    bool wasAborted() { return getFlags(WCF_ABORT_REQUESTED); }

    const std::string& getName() const { return mWorkerClassName; }

protected:
    // called from WORKER THREAD
    void setWorking(bool working);

    // Call from doWork only to avoid eating up cpu time.
    // Returns true if work has been aborted
    // yields the current thread and calls mWorkerThread->checkPause()
    bool yield();

    void setWorkerThread(LLWorkerThread* workerthread);

    // addWork(): calls startWork, adds doWork() to queue
    void addWork(S32 param);

    // abortWork(): requests that work be aborted
    void abortWork(bool autocomplete);

    // checkWork(): if doWork is complete or aborted, call endWork() and return true
    bool checkWork(bool aborting = false);

private:
    void setFlags(U32 flags) { mWorkFlags = mWorkFlags | flags; }
    void clearFlags(U32 flags) { mWorkFlags = mWorkFlags & ~flags; }
    U32  getFlags() { return mWorkFlags; }
public:
    bool getFlags(U32 flags) { return (mWorkFlags & flags) != 0; }

private:
    // pure virtuals
    virtual void startWork(S32 param)=0; // called from addWork() (MAIN THREAD)
    virtual void endWork(S32 param, bool aborted)=0; // called from doWork() (MAIN THREAD)

protected:
    LLWorkerThread* mWorkerThread;
    std::string mWorkerClassName;
    handle_t mRequestHandle;

private:
    LLMutex mMutex;
    LLAtomicU32 mWorkFlags;
};

//============================================================================


#endif // LL_LLWORKERTHREAD_H