aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/OpenSim/Region/ScriptEngine/DotNetEngine/EventQueueManager.cs
blob: 31c0d4da20953295dcd230f151e35342fcfd7da4 (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
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
/*
 * Copyright (c) Contributors, http://opensimulator.org/
 * See CONTRIBUTORS.TXT for a full list of copyright holders.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the OpenSim Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

using System;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;
using OpenMetaverse;
using OpenSim.Region.ScriptEngine.Shared;
using log4net;

namespace OpenSim.Region.ScriptEngine.DotNetEngine
{
    /// <summary>
    /// EventQueueManager handles event queues
    /// Events are queued and executed in separate thread
    /// </summary>
    [Serializable]
    public class EventQueueManager
    {
        //
        // Class is instanced in "ScriptEngine" and used by "EventManager" which is also instanced in "ScriptEngine".
        //
        // Class purpose is to queue and execute functions that are received by "EventManager":
        //   - allowing "EventManager" to release its event thread immediately, thus not interrupting server execution.
        //   - allowing us to prioritize and control execution of script functions.
        // Class can use multiple threads for simultaneous execution. Mutexes are used for thread safety.
        //
        // 1. Hold an execution queue for scripts
        // 2. Use threads to process queue, each thread executes one script function on each pass.
        // 3. Catch any script error and process it
        //
        //
        // Notes:
        // * Current execution load balancing is optimized for 1 thread, and can cause unfair execute balancing between scripts.
        //   Not noticeable unless server is under high load.
        //

        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

        public ScriptEngine m_ScriptEngine;

        /// <summary>
        /// List of threads (classes) processing event queue
        /// Note that this may or may not be a reference to a static object depending on PrivateRegionThreads config setting.
        /// </summary>
        internal static List<EventQueueThreadClass> eventQueueThreads = new List<EventQueueThreadClass>();                             // Thread pool that we work on
        /// <summary>
        /// Locking access to eventQueueThreads AND staticGlobalEventQueueThreads.
        /// </summary>
//        private object eventQueueThreadsLock = new object();
        // Static objects for referencing the objects above if we don't have private threads:
        //internal static List<EventQueueThreadClass> staticEventQueueThreads;                // A static reference used if we don't use private threads
//        internal static object staticEventQueueThreadsLock;                                 // Statick lock object reference for same reason

        /// <summary>
        /// Global static list of all threads (classes) processing event queue -- used by max enforcment thread
        /// </summary>
        //private List<EventQueueThreadClass> staticGlobalEventQueueThreads = new List<EventQueueThreadClass>();

        /// <summary>
        /// Used internally to specify how many threads should exit gracefully
        /// </summary>
        public static int ThreadsToExit;
        public static object ThreadsToExitLock = new object();


        //public object queueLock = new object(); // Mutex lock object

        /// <summary>
        /// How many threads to process queue with
        /// </summary>
        internal static int numberOfThreads;

        internal static int EventExecutionMaxQueueSize;

        /// <summary>
        /// Maximum time one function can use for execution before we perform a thread kill.
        /// </summary>
        private static int maxFunctionExecutionTimems
        {
            get { return (int)(maxFunctionExecutionTimens / 10000); }
            set { maxFunctionExecutionTimens = value * 10000; }
        }

        /// <summary>
        /// Contains nanoseconds version of maxFunctionExecutionTimems so that it matches time calculations better (performance reasons).
        /// WARNING! ONLY UPDATE maxFunctionExecutionTimems, NEVER THIS DIRECTLY.
        /// </summary>
        public static long maxFunctionExecutionTimens;
        /// <summary>
        /// Enforce max execution time
        /// </summary>
        public static bool EnforceMaxExecutionTime;
        /// <summary>
        /// Kill script (unload) when it exceeds execution time
        /// </summary>
        private static bool KillScriptOnMaxFunctionExecutionTime;

        /// <summary>
        /// List of localID locks for mutex processing of script events
        /// </summary>
        private List<uint> objectLocks = new List<uint>();
        private object tryLockLock = new object(); // Mutex lock object

        /// <summary>
        /// Queue containing events waiting to be executed
        /// </summary>
        public Queue<QueueItemStruct> eventQueue = new Queue<QueueItemStruct>();

        #region " Queue structures "
        /// <summary>
        /// Queue item structure
        /// </summary>
        public struct QueueItemStruct
        {
            public uint localID;
            public UUID itemID;
            public string functionName;
            public DetectParams[] llDetectParams;
            public object[] param;
            public Dictionary<KeyValuePair<int,int>,KeyValuePair<int,int>>
                    LineMap;
        }

        #endregion

        #region " Initialization / Startup "
        public EventQueueManager(ScriptEngine _ScriptEngine)
        {
            m_ScriptEngine = _ScriptEngine;

            ReadConfig();
            AdjustNumberOfScriptThreads();
        }

        public void ReadConfig()
        {
            // Refresh config
            numberOfThreads = m_ScriptEngine.ScriptConfigSource.GetInt("NumberOfScriptThreads", 2);
            maxFunctionExecutionTimems = m_ScriptEngine.ScriptConfigSource.GetInt("MaxEventExecutionTimeMs", 5000);
            EnforceMaxExecutionTime = m_ScriptEngine.ScriptConfigSource.GetBoolean("EnforceMaxEventExecutionTime", false);
            KillScriptOnMaxFunctionExecutionTime = m_ScriptEngine.ScriptConfigSource.GetBoolean("DeactivateScriptOnTimeout", false);
            EventExecutionMaxQueueSize = m_ScriptEngine.ScriptConfigSource.GetInt("EventExecutionMaxQueueSize", 300);

            // Now refresh config in all threads
            lock (eventQueueThreads)
            {
                foreach (EventQueueThreadClass EventQueueThread in eventQueueThreads)
                {
                    EventQueueThread.ReadConfig();
                }
            }
        }

        #endregion

        #region " Shutdown all threads "
        ~EventQueueManager()
        {
            Stop();
        }

        private void Stop()
        {
            if (eventQueueThreads != null)
            {
                // Kill worker threads
                lock (eventQueueThreads)
                {
                    foreach (EventQueueThreadClass EventQueueThread in new ArrayList(eventQueueThreads))
                    {
                        AbortThreadClass(EventQueueThread);
                    }
                    //eventQueueThreads.Clear();
                    //staticGlobalEventQueueThreads.Clear();
                }
            }

                // Remove all entries from our event queue
                lock (eventQueue)
                {
                    eventQueue.Clear();
                }
        }

        #endregion

        #region " Start / stop script execution threads (ThreadClasses) "
        private void StartNewThreadClass()
        {
            EventQueueThreadClass eqtc = new EventQueueThreadClass();
            eventQueueThreads.Add(eqtc);
            //m_log.Debug("[" + m_ScriptEngine.ScriptEngineName + "]: Started new script execution thread. Current thread count: " + eventQueueThreads.Count);
        }

        private void AbortThreadClass(EventQueueThreadClass threadClass)
        {
            if (eventQueueThreads.Contains(threadClass))
                eventQueueThreads.Remove(threadClass);

            try
            {
                threadClass.Stop();
            }
            catch (Exception)
            {
                //m_log.Error("[" + m_ScriptEngine.ScriptEngineName + ":EventQueueManager]: If you see this, could you please report it to Tedd:");
                //m_log.Error("[" + m_ScriptEngine.ScriptEngineName + ":EventQueueManager]: Script thread execution timeout kill ended in exception: " + ex.ToString());
            }
            //m_log.Debug("[" + m_ScriptEngine.ScriptEngineName + "]: Killed script execution thread. Remaining thread count: " + eventQueueThreads.Count);
        }
        #endregion

        #region " Mutex locks for queue access "
        /// <summary>
        /// Try to get a mutex lock on localID
        /// </summary>
        /// <param name="localID"></param>
        /// <returns></returns>
        public bool TryLock(uint localID)
        {
            lock (tryLockLock)
            {
                if (objectLocks.Contains(localID) == true)
                {
                    return false;
                }
                else
                {
                    objectLocks.Add(localID);
                    return true;
                }
            }
        }

        /// <summary>
        /// Release mutex lock on localID
        /// </summary>
        /// <param name="localID"></param>
        public void ReleaseLock(uint localID)
        {
            lock (tryLockLock)
            {
                if (objectLocks.Contains(localID) == true)
                {
                    objectLocks.Remove(localID);
                }
            }
        }
        #endregion
        
        #region " Check execution queue for a specified Event"
        /// <summary>
        /// checks to see if a specified event type is already in the queue
        /// </summary>
        /// <param name="localID">Region object ID</param>
        /// <param name="FunctionName">Name of the function, will be state + "_event_" + FunctionName</param>
        /// <returns>true if event is found , false if not found</returns>
        /// 
        public bool CheckEeventQueueForEvent(uint localID, string FunctionName)
        {
            if (eventQueue.Count > 0)
            {
                lock (eventQueue)
                {
                    foreach (EventQueueManager.QueueItemStruct QIS in eventQueue)
                    {
                        if ((QIS.functionName == FunctionName) && (QIS.localID == localID))
                            return true;
                    }
                }
            }
            return false;
        }
        #endregion

        #region " Add events to execution queue "
        /// <summary>
        /// Add event to event execution queue
        /// </summary>
        /// <param name="localID">Region object ID</param>
        /// <param name="FunctionName">Name of the function, will be state + "_event_" + FunctionName</param>
        /// <param name="param">Array of parameters to match event mask</param>
        public bool AddToObjectQueue(uint localID, string FunctionName, DetectParams[] qParams, params object[] param)
        {
            // Determine all scripts in Object and add to their queue
            //myScriptEngine.log.Info("[" + ScriptEngineName + "]: EventQueueManager Adding localID: " + localID + ", FunctionName: " + FunctionName);

            // Do we have any scripts in this object at all? If not, return
            if (m_ScriptEngine.m_ScriptManager.Scripts.ContainsKey(localID) == false)
            {
                //Console.WriteLine("Event \String.Empty + FunctionName + "\" for localID: " + localID + ". No scripts found on this localID.");
                return false;
            }

            List<UUID> scriptKeys =
                m_ScriptEngine.m_ScriptManager.GetScriptKeys(localID);

            foreach (UUID itemID in scriptKeys)
            {
                // Add to each script in that object
                // TODO: Some scripts may not subscribe to this event. Should we NOT add it? Does it matter?
                AddToScriptQueue(localID, itemID, FunctionName, qParams, param);
            }
            return true;
        }

        /// <summary>
        /// Add event to event execution queue
        /// </summary>
        /// <param name="localID">Region object ID</param>
        /// <param name="itemID">Region script ID</param>
        /// <param name="FunctionName">Name of the function, will be state + "_event_" + FunctionName</param>
        /// <param name="param">Array of parameters to match event mask</param>
        public bool AddToScriptQueue(uint localID, UUID itemID, string FunctionName, DetectParams[] qParams, params object[] param)
        {
            List<UUID> keylist = m_ScriptEngine.m_ScriptManager.GetScriptKeys(localID);

            if (!keylist.Contains(itemID)) // We don't manage that script
            {
                return false;
            }

            lock (eventQueue)
            {
                if (eventQueue.Count >= EventExecutionMaxQueueSize)
                {
                    m_log.Error("[" + m_ScriptEngine.ScriptEngineName + "]: ERROR: Event execution queue item count is at " + eventQueue.Count + ". Config variable \"EventExecutionMaxQueueSize\" is set to " + EventExecutionMaxQueueSize + ", so ignoring new event.");
                    m_log.Error("[" + m_ScriptEngine.ScriptEngineName + "]: Event ignored: localID: " + localID + ", itemID: " + itemID + ", FunctionName: " + FunctionName);
                    return false;
                }

                InstanceData id = m_ScriptEngine.m_ScriptManager.GetScript(
                        localID, itemID);

                // Create a structure and add data
                QueueItemStruct QIS = new QueueItemStruct();
                QIS.localID = localID;
                QIS.itemID = itemID;
                QIS.functionName = FunctionName;
                QIS.llDetectParams = qParams;
                QIS.param = param;
                if (id != null)
                    QIS.LineMap = id.LineMap;

                // Add it to queue
                eventQueue.Enqueue(QIS);
            }
            return true;
        }
        #endregion

        #region " Maintenance thread "

        /// <summary>
        /// Adjust number of script thread classes. It can start new, but if it needs to stop it will just set number of threads in "ThreadsToExit" and threads will have to exit themselves.
        /// Called from MaintenanceThread
        /// </summary>
        public void AdjustNumberOfScriptThreads()
        {
            // Is there anything here for us to do?
            if (eventQueueThreads.Count == numberOfThreads)
                return;

            lock (eventQueueThreads)
            {
                int diff = numberOfThreads - eventQueueThreads.Count;
                // Positive number: Start
                // Negative number: too many are running
                if (diff > 0)
                {
                    // We need to add more threads
                    for (int ThreadCount = eventQueueThreads.Count; ThreadCount < numberOfThreads; ThreadCount++)
                    {
                        StartNewThreadClass();
                    }
                }
                if (diff < 0)
                {
                    // We need to kill some threads
                    lock (ThreadsToExitLock)
                    {
                        ThreadsToExit = Math.Abs(diff);
                    }
                }
            }
        }

        /// <summary>
        /// Check if any thread class has been executing an event too long
        /// </summary>
        public void CheckScriptMaxExecTime()
        {
            // Iterate through all ScriptThreadClasses and check how long their current function has been executing
            lock (eventQueueThreads)
            {
                foreach (EventQueueThreadClass EventQueueThread in eventQueueThreads)
                {
                    // Is thread currently executing anything?
                    if (EventQueueThread.InExecution)
                    {
                        // Has execution time expired?
                        if (DateTime.Now.Ticks - EventQueueThread.LastExecutionStarted >
                            maxFunctionExecutionTimens)
                        {
                            // Yes! We need to kill this thread!

                            // Set flag if script should be removed or not
                            EventQueueThread.KillCurrentScript = KillScriptOnMaxFunctionExecutionTime;

                            // Abort this thread
                            AbortThreadClass(EventQueueThread);

                            // We do not need to start another, MaintenenceThread will do that for us
                            //StartNewThreadClass();
                        }
                    }
                }
            }
        }
        #endregion

        ///// <summary>
        ///// If set to true then threads and stuff should try to make a graceful exit
        ///// </summary>
        //public bool PleaseShutdown
        //{
        //    get { return _PleaseShutdown; }
        //    set { _PleaseShutdown = value; }
        //}
        //private bool _PleaseShutdown = false;
    }
}