diff options
Merge branch 'master' of melanie@opensimulator.org:/var/git/opensim
Diffstat (limited to '')
| -rw-r--r-- | ThirdParty/SmartThreadPool/WorkItemsQueue.cs | 1245 |
1 files changed, 645 insertions, 600 deletions
diff --git a/ThirdParty/SmartThreadPool/WorkItemsQueue.cs b/ThirdParty/SmartThreadPool/WorkItemsQueue.cs index af5af07..156a131 100644 --- a/ThirdParty/SmartThreadPool/WorkItemsQueue.cs +++ b/ThirdParty/SmartThreadPool/WorkItemsQueue.cs | |||
| @@ -1,600 +1,645 @@ | |||
| 1 | // Ami Bar | 1 | using System; |
| 2 | // amibar@gmail.com | 2 | using System.Collections.Generic; |
| 3 | 3 | using System.Threading; | |
| 4 | using System; | 4 | |
| 5 | using System.Threading; | 5 | namespace Amib.Threading.Internal |
| 6 | 6 | { | |
| 7 | namespace Amib.Threading.Internal | 7 | #region WorkItemsQueue class |
| 8 | { | 8 | |
| 9 | #region WorkItemsQueue class | 9 | /// <summary> |
| 10 | 10 | /// WorkItemsQueue class. | |
| 11 | /// <summary> | 11 | /// </summary> |
| 12 | /// WorkItemsQueue class. | 12 | public class WorkItemsQueue : IDisposable |
| 13 | /// </summary> | 13 | { |
| 14 | public class WorkItemsQueue : IDisposable | 14 | #region Member variables |
| 15 | { | 15 | |
| 16 | #region Member variables | 16 | /// <summary> |
| 17 | 17 | /// Waiters queue (implemented as stack). | |
| 18 | /// <summary> | 18 | /// </summary> |
| 19 | /// Waiters queue (implemented as stack). | 19 | private readonly WaiterEntry _headWaiterEntry = new WaiterEntry(); |
| 20 | /// </summary> | 20 | |
| 21 | private WaiterEntry _headWaiterEntry = new WaiterEntry(); | 21 | /// <summary> |
| 22 | 22 | /// Waiters count | |
| 23 | /// <summary> | 23 | /// </summary> |
| 24 | /// Waiters count | 24 | private int _waitersCount = 0; |
| 25 | /// </summary> | 25 | |
| 26 | private int _waitersCount = 0; | 26 | /// <summary> |
| 27 | 27 | /// Work items queue | |
| 28 | /// <summary> | 28 | /// </summary> |
| 29 | /// Work items queue | 29 | private readonly PriorityQueue _workItems = new PriorityQueue(); |
| 30 | /// </summary> | 30 | |
| 31 | private PriorityQueue _workItems = new PriorityQueue(); | 31 | /// <summary> |
| 32 | 32 | /// Indicate that work items are allowed to be queued | |
| 33 | /// <summary> | 33 | /// </summary> |
| 34 | /// Indicate that work items are allowed to be queued | 34 | private bool _isWorkItemsQueueActive = true; |
| 35 | /// </summary> | 35 | |
| 36 | private bool _isWorkItemsQueueActive = true; | 36 | |
| 37 | 37 | #if (WINDOWS_PHONE) | |
| 38 | /// <summary> | 38 | private static readonly Dictionary<int, WaiterEntry> _waiterEntries = new Dictionary<int, WaiterEntry>(); |
| 39 | /// Each thread in the thread pool keeps its own waiter entry. | 39 | #elif (_WINDOWS_CE) |
| 40 | /// </summary> | 40 | private static LocalDataStoreSlot _waiterEntrySlot = Thread.AllocateDataSlot(); |
| 41 | [ThreadStatic] | 41 | #else |
| 42 | private static WaiterEntry _waiterEntry; | 42 | |
| 43 | 43 | [ThreadStatic] | |
| 44 | /// <summary> | 44 | private static WaiterEntry _waiterEntry; |
| 45 | /// A flag that indicates if the WorkItemsQueue has been disposed. | 45 | #endif |
| 46 | /// </summary> | 46 | |
| 47 | private bool _isDisposed = false; | 47 | |
| 48 | 48 | /// <summary> | |
| 49 | #endregion | 49 | /// Each thread in the thread pool keeps its own waiter entry. |
| 50 | 50 | /// </summary> | |
| 51 | #region Public properties | 51 | private static WaiterEntry CurrentWaiterEntry |
| 52 | 52 | { | |
| 53 | /// <summary> | 53 | #if (WINDOWS_PHONE) |
| 54 | /// Returns the current number of work items in the queue | 54 | get |
| 55 | /// </summary> | 55 | { |
| 56 | public int Count | 56 | lock (_waiterEntries) |
| 57 | { | 57 | { |
| 58 | get | 58 | WaiterEntry waiterEntry; |
| 59 | { | 59 | if (_waiterEntries.TryGetValue(Thread.CurrentThread.ManagedThreadId, out waiterEntry)) |
| 60 | lock(this) | 60 | { |
| 61 | { | 61 | return waiterEntry; |
| 62 | ValidateNotDisposed(); | 62 | } |
| 63 | return _workItems.Count; | 63 | } |
| 64 | } | 64 | return null; |
| 65 | } | 65 | } |
| 66 | } | 66 | set |
| 67 | 67 | { | |
| 68 | /// <summary> | 68 | lock (_waiterEntries) |
| 69 | /// Returns the current number of waiters | 69 | { |
| 70 | /// </summary> | 70 | _waiterEntries[Thread.CurrentThread.ManagedThreadId] = value; |
| 71 | public int WaitersCount | 71 | } |
| 72 | { | 72 | } |
| 73 | get | 73 | #elif (_WINDOWS_CE) |
| 74 | { | 74 | get |
| 75 | lock(this) | 75 | { |
| 76 | { | 76 | return Thread.GetData(_waiterEntrySlot) as WaiterEntry; |
| 77 | ValidateNotDisposed(); | 77 | } |
| 78 | return _waitersCount; | 78 | set |
| 79 | } | 79 | { |
| 80 | } | 80 | Thread.SetData(_waiterEntrySlot, value); |
| 81 | } | 81 | } |
| 82 | 82 | #else | |
| 83 | 83 | get | |
| 84 | #endregion | 84 | { |
| 85 | 85 | return _waiterEntry; | |
| 86 | #region Public methods | 86 | } |
| 87 | 87 | set | |
| 88 | /// <summary> | 88 | { |
| 89 | /// Enqueue a work item to the queue. | 89 | _waiterEntry = value; |
| 90 | /// </summary> | 90 | } |
| 91 | public bool EnqueueWorkItem(WorkItem workItem) | 91 | #endif |
| 92 | { | 92 | } |
| 93 | // A work item cannot be null, since null is used in the | 93 | |
| 94 | // WaitForWorkItem() method to indicate timeout or cancel | 94 | /// <summary> |
| 95 | if (null == workItem) | 95 | /// A flag that indicates if the WorkItemsQueue has been disposed. |
| 96 | { | 96 | /// </summary> |
| 97 | throw new ArgumentNullException("workItem" , "workItem cannot be null"); | 97 | private bool _isDisposed = false; |
| 98 | } | 98 | |
| 99 | 99 | #endregion | |
| 100 | bool enqueue = true; | 100 | |
| 101 | 101 | #region Public properties | |
| 102 | // First check if there is a waiter waiting for work item. During | 102 | |
| 103 | // the check, timed out waiters are ignored. If there is no | 103 | /// <summary> |
| 104 | // waiter then the work item is queued. | 104 | /// Returns the current number of work items in the queue |
| 105 | lock(this) | 105 | /// </summary> |
| 106 | { | 106 | public int Count |
| 107 | ValidateNotDisposed(); | 107 | { |
| 108 | 108 | get | |
| 109 | if (!_isWorkItemsQueueActive) | 109 | { |
| 110 | { | 110 | return _workItems.Count; |
| 111 | return false; | 111 | } |
| 112 | } | 112 | } |
| 113 | 113 | ||
| 114 | while(_waitersCount > 0) | 114 | /// <summary> |
| 115 | { | 115 | /// Returns the current number of waiters |
| 116 | // Dequeue a waiter. | 116 | /// </summary> |
| 117 | WaiterEntry waiterEntry = PopWaiter(); | 117 | public int WaitersCount |
| 118 | 118 | { | |
| 119 | // Signal the waiter. On success break the loop | 119 | get |
| 120 | if (waiterEntry.Signal(workItem)) | 120 | { |
| 121 | { | 121 | return _waitersCount; |
| 122 | enqueue = false; | 122 | } |
| 123 | break; | 123 | } |
| 124 | } | 124 | |
| 125 | } | 125 | |
| 126 | 126 | #endregion | |
| 127 | if (enqueue) | 127 | |
| 128 | { | 128 | #region Public methods |
| 129 | // Enqueue the work item | 129 | |
| 130 | _workItems.Enqueue(workItem); | 130 | /// <summary> |
| 131 | } | 131 | /// Enqueue a work item to the queue. |
| 132 | } | 132 | /// </summary> |
| 133 | return true; | 133 | public bool EnqueueWorkItem(WorkItem workItem) |
| 134 | } | 134 | { |
| 135 | 135 | // A work item cannot be null, since null is used in the | |
| 136 | 136 | // WaitForWorkItem() method to indicate timeout or cancel | |
| 137 | /// <summary> | 137 | if (null == workItem) |
| 138 | /// Waits for a work item or exits on timeout or cancel | 138 | { |
| 139 | /// </summary> | 139 | throw new ArgumentNullException("workItem" , "workItem cannot be null"); |
| 140 | /// <param name="millisecondsTimeout">Timeout in milliseconds</param> | 140 | } |
| 141 | /// <param name="cancelEvent">Cancel wait handle</param> | 141 | |
| 142 | /// <returns>Returns true if the resource was granted</returns> | 142 | bool enqueue = true; |
| 143 | public WorkItem DequeueWorkItem( | 143 | |
| 144 | int millisecondsTimeout, | 144 | // First check if there is a waiter waiting for work item. During |
| 145 | WaitHandle cancelEvent) | 145 | // the check, timed out waiters are ignored. If there is no |
| 146 | { | 146 | // waiter then the work item is queued. |
| 147 | /// This method cause the caller to wait for a work item. | 147 | lock(this) |
| 148 | /// If there is at least one waiting work item then the | 148 | { |
| 149 | /// method returns immidiately with true. | 149 | ValidateNotDisposed(); |
| 150 | /// | 150 | |
| 151 | /// If there are no waiting work items then the caller | 151 | if (!_isWorkItemsQueueActive) |
| 152 | /// is queued between other waiters for a work item to arrive. | 152 | { |
| 153 | /// | 153 | return false; |
| 154 | /// If a work item didn't come within millisecondsTimeout or | 154 | } |
| 155 | /// the user canceled the wait by signaling the cancelEvent | 155 | |
| 156 | /// then the method returns false to indicate that the caller | 156 | while(_waitersCount > 0) |
| 157 | /// didn't get a work item. | 157 | { |
| 158 | 158 | // Dequeue a waiter. | |
| 159 | WaiterEntry waiterEntry = null; | 159 | WaiterEntry waiterEntry = PopWaiter(); |
| 160 | WorkItem workItem = null; | 160 | |
| 161 | 161 | // Signal the waiter. On success break the loop | |
| 162 | lock(this) | 162 | if (waiterEntry.Signal(workItem)) |
| 163 | { | 163 | { |
| 164 | ValidateNotDisposed(); | 164 | enqueue = false; |
| 165 | 165 | break; | |
| 166 | // If there are waiting work items then take one and return. | 166 | } |
| 167 | if (_workItems.Count > 0) | 167 | } |
| 168 | { | 168 | |
| 169 | workItem = _workItems.Dequeue() as WorkItem; | 169 | if (enqueue) |
| 170 | return workItem; | 170 | { |
| 171 | } | 171 | // Enqueue the work item |
| 172 | // No waiting work items ... | 172 | _workItems.Enqueue(workItem); |
| 173 | else | 173 | } |
| 174 | { | 174 | } |
| 175 | // Get the wait entry for the waiters queue | 175 | return true; |
| 176 | waiterEntry = GetThreadWaiterEntry(); | 176 | } |
| 177 | 177 | ||
| 178 | // Put the waiter with the other waiters | 178 | |
| 179 | PushWaiter(waiterEntry); | 179 | /// <summary> |
| 180 | } | 180 | /// Waits for a work item or exits on timeout or cancel |
| 181 | } | 181 | /// </summary> |
| 182 | 182 | /// <param name="millisecondsTimeout">Timeout in milliseconds</param> | |
| 183 | // Prepare array of wait handle for the WaitHandle.WaitAny() | 183 | /// <param name="cancelEvent">Cancel wait handle</param> |
| 184 | WaitHandle [] waitHandles = new WaitHandle [] { | 184 | /// <returns>Returns true if the resource was granted</returns> |
| 185 | waiterEntry.WaitHandle, | 185 | public WorkItem DequeueWorkItem( |
| 186 | cancelEvent }; | 186 | int millisecondsTimeout, |
| 187 | 187 | WaitHandle cancelEvent) | |
| 188 | // Wait for an available resource, cancel event, or timeout. | 188 | { |
| 189 | 189 | // This method cause the caller to wait for a work item. | |
| 190 | // During the wait we are supposes to exit the synchronization | 190 | // If there is at least one waiting work item then the |
| 191 | // domain. (Placing true as the third argument of the WaitAny()) | 191 | // method returns immidiately with it. |
| 192 | // It just doesn't work, I don't know why, so I have lock(this) | 192 | // |
| 193 | // statments insted of one. | 193 | // If there are no waiting work items then the caller |
| 194 | 194 | // is queued between other waiters for a work item to arrive. | |
| 195 | int index = WaitHandle.WaitAny( | 195 | // |
| 196 | waitHandles, | 196 | // If a work item didn't come within millisecondsTimeout or |
| 197 | millisecondsTimeout, | 197 | // the user canceled the wait by signaling the cancelEvent |
| 198 | true); | 198 | // then the method returns null to indicate that the caller |
| 199 | 199 | // didn't get a work item. | |
| 200 | lock(this) | 200 | |
| 201 | { | 201 | WaiterEntry waiterEntry; |
| 202 | // success is true if it got a work item. | 202 | WorkItem workItem = null; |
| 203 | bool success = (0 == index); | 203 | lock (this) |
| 204 | 204 | { | |
| 205 | // The timeout variable is used only for readability. | 205 | ValidateNotDisposed(); |
| 206 | // (We treat cancel as timeout) | 206 | |
| 207 | bool timeout = !success; | 207 | // If there are waiting work items then take one and return. |
| 208 | 208 | if (_workItems.Count > 0) | |
| 209 | // On timeout update the waiterEntry that it is timed out | 209 | { |
| 210 | if (timeout) | 210 | workItem = _workItems.Dequeue() as WorkItem; |
| 211 | { | 211 | return workItem; |
| 212 | // The Timeout() fails if the waiter has already been signaled | 212 | } |
| 213 | timeout = waiterEntry.Timeout(); | 213 | |
| 214 | 214 | // No waiting work items ... | |
| 215 | // On timeout remove the waiter from the queue. | 215 | |
| 216 | // Note that the complexity is O(1). | 216 | // Get the waiter entry for the waiters queue |
| 217 | if(timeout) | 217 | waiterEntry = GetThreadWaiterEntry(); |
| 218 | { | 218 | |
| 219 | RemoveWaiter(waiterEntry, false); | 219 | // Put the waiter with the other waiters |
| 220 | } | 220 | PushWaiter(waiterEntry); |
| 221 | 221 | } | |
| 222 | // Again readability | 222 | |
| 223 | success = !timeout; | 223 | // Prepare array of wait handle for the WaitHandle.WaitAny() |
| 224 | } | 224 | WaitHandle [] waitHandles = new WaitHandle[] { |
| 225 | 225 | waiterEntry.WaitHandle, | |
| 226 | // On success return the work item | 226 | cancelEvent }; |
| 227 | if (success) | 227 | |
| 228 | { | 228 | // Wait for an available resource, cancel event, or timeout. |
| 229 | workItem = waiterEntry.WorkItem; | 229 | |
| 230 | 230 | // During the wait we are supposes to exit the synchronization | |
| 231 | if (null == workItem) | 231 | // domain. (Placing true as the third argument of the WaitAny()) |
| 232 | { | 232 | // It just doesn't work, I don't know why, so I have two lock(this) |
| 233 | workItem = _workItems.Dequeue() as WorkItem; | 233 | // statments instead of one. |
| 234 | } | 234 | |
| 235 | } | 235 | int index = STPEventWaitHandle.WaitAny( |
| 236 | } | 236 | waitHandles, |
| 237 | // On failure return null. | 237 | millisecondsTimeout, |
| 238 | return workItem; | 238 | true); |
| 239 | } | 239 | |
| 240 | 240 | lock(this) | |
| 241 | /// <summary> | 241 | { |
| 242 | /// Cleanup the work items queue, hence no more work | 242 | // success is true if it got a work item. |
| 243 | /// items are allowed to be queue | 243 | bool success = (0 == index); |
| 244 | /// </summary> | 244 | |
| 245 | protected virtual void Cleanup() | 245 | // The timeout variable is used only for readability. |
| 246 | { | 246 | // (We treat cancel as timeout) |
| 247 | lock(this) | 247 | bool timeout = !success; |
| 248 | { | 248 | |
| 249 | // Deactivate only once | 249 | // On timeout update the waiterEntry that it is timed out |
| 250 | if (!_isWorkItemsQueueActive) | 250 | if (timeout) |
| 251 | { | 251 | { |
| 252 | return; | 252 | // The Timeout() fails if the waiter has already been signaled |
| 253 | } | 253 | timeout = waiterEntry.Timeout(); |
| 254 | 254 | ||
| 255 | // Don't queue more work items | 255 | // On timeout remove the waiter from the queue. |
| 256 | _isWorkItemsQueueActive = false; | 256 | // Note that the complexity is O(1). |
| 257 | 257 | if(timeout) | |
| 258 | foreach(WorkItem workItem in _workItems) | 258 | { |
| 259 | { | 259 | RemoveWaiter(waiterEntry, false); |
| 260 | workItem.DisposeOfState(); | 260 | } |
| 261 | } | 261 | |
| 262 | 262 | // Again readability | |
| 263 | // Clear the work items that are already queued | 263 | success = !timeout; |
| 264 | _workItems.Clear(); | 264 | } |
| 265 | 265 | ||
| 266 | // Note: | 266 | // On success return the work item |
| 267 | // I don't iterate over the queue and dispose of work items's states, | 267 | if (success) |
| 268 | // since if a work item has a state object that is still in use in the | 268 | { |
| 269 | // application then I must not dispose it. | 269 | workItem = waiterEntry.WorkItem; |
| 270 | 270 | ||
| 271 | // Tell the waiters that they were timed out. | 271 | if (null == workItem) |
| 272 | // It won't signal them to exit, but to ignore their | 272 | { |
| 273 | // next work item. | 273 | workItem = _workItems.Dequeue() as WorkItem; |
| 274 | while(_waitersCount > 0) | 274 | } |
| 275 | { | 275 | } |
| 276 | WaiterEntry waiterEntry = PopWaiter(); | 276 | } |
| 277 | waiterEntry.Timeout(); | 277 | // On failure return null. |
| 278 | } | 278 | return workItem; |
| 279 | } | 279 | } |
| 280 | } | 280 | |
| 281 | 281 | /// <summary> | |
| 282 | #endregion | 282 | /// Cleanup the work items queue, hence no more work |
| 283 | 283 | /// items are allowed to be queue | |
| 284 | #region Private methods | 284 | /// </summary> |
| 285 | 285 | private void Cleanup() | |
| 286 | /// <summary> | 286 | { |
| 287 | /// Returns the WaiterEntry of the current thread | 287 | lock(this) |
| 288 | /// </summary> | 288 | { |
| 289 | /// <returns></returns> | 289 | // Deactivate only once |
| 290 | /// In order to avoid creation and destuction of WaiterEntry | 290 | if (!_isWorkItemsQueueActive) |
| 291 | /// objects each thread has its own WaiterEntry object. | 291 | { |
| 292 | private WaiterEntry GetThreadWaiterEntry() | 292 | return; |
| 293 | { | 293 | } |
| 294 | if (null == _waiterEntry) | 294 | |
| 295 | { | 295 | // Don't queue more work items |
| 296 | _waiterEntry = new WaiterEntry(); | 296 | _isWorkItemsQueueActive = false; |
| 297 | } | 297 | |
| 298 | _waiterEntry.Reset(); | 298 | foreach(WorkItem workItem in _workItems) |
| 299 | return _waiterEntry; | 299 | { |
| 300 | } | 300 | workItem.DisposeOfState(); |
| 301 | 301 | } | |
| 302 | #region Waiters stack methods | 302 | |
| 303 | 303 | // Clear the work items that are already queued | |
| 304 | /// <summary> | 304 | _workItems.Clear(); |
| 305 | /// Push a new waiter into the waiter's stack | 305 | |
| 306 | /// </summary> | 306 | // Note: |
| 307 | /// <param name="newWaiterEntry">A waiter to put in the stack</param> | 307 | // I don't iterate over the queue and dispose of work items's states, |
| 308 | public void PushWaiter(WaiterEntry newWaiterEntry) | 308 | // since if a work item has a state object that is still in use in the |
| 309 | { | 309 | // application then I must not dispose it. |
| 310 | // Remove the waiter if it is already in the stack and | 310 | |
| 311 | // update waiter's count as needed | 311 | // Tell the waiters that they were timed out. |
| 312 | RemoveWaiter(newWaiterEntry, false); | 312 | // It won't signal them to exit, but to ignore their |
| 313 | 313 | // next work item. | |
| 314 | // If the stack is empty then newWaiterEntry is the new head of the stack | 314 | while(_waitersCount > 0) |
| 315 | if (null == _headWaiterEntry._nextWaiterEntry) | 315 | { |
| 316 | { | 316 | WaiterEntry waiterEntry = PopWaiter(); |
| 317 | _headWaiterEntry._nextWaiterEntry = newWaiterEntry; | 317 | waiterEntry.Timeout(); |
| 318 | newWaiterEntry._prevWaiterEntry = _headWaiterEntry; | 318 | } |
| 319 | 319 | } | |
| 320 | } | 320 | } |
| 321 | // If the stack is not empty then put newWaiterEntry as the new head | 321 | |
| 322 | // of the stack. | 322 | public object[] GetStates() |
| 323 | else | 323 | { |
| 324 | { | 324 | lock (this) |
| 325 | // Save the old first waiter entry | 325 | { |
| 326 | WaiterEntry oldFirstWaiterEntry = _headWaiterEntry._nextWaiterEntry; | 326 | object[] states = new object[_workItems.Count]; |
| 327 | 327 | int i = 0; | |
| 328 | // Update the links | 328 | foreach (WorkItem workItem in _workItems) |
| 329 | _headWaiterEntry._nextWaiterEntry = newWaiterEntry; | 329 | { |
| 330 | newWaiterEntry._nextWaiterEntry = oldFirstWaiterEntry; | 330 | states[i] = workItem.GetWorkItemResult().State; |
| 331 | newWaiterEntry._prevWaiterEntry = _headWaiterEntry; | 331 | ++i; |
| 332 | oldFirstWaiterEntry._prevWaiterEntry = newWaiterEntry; | 332 | } |
| 333 | } | 333 | return states; |
| 334 | 334 | } | |
| 335 | // Increment the number of waiters | 335 | } |
| 336 | ++_waitersCount; | 336 | |
| 337 | } | 337 | #endregion |
| 338 | 338 | ||
| 339 | /// <summary> | 339 | #region Private methods |
| 340 | /// Pop a waiter from the waiter's stack | 340 | |
| 341 | /// </summary> | 341 | /// <summary> |
| 342 | /// <returns>Returns the first waiter in the stack</returns> | 342 | /// Returns the WaiterEntry of the current thread |
| 343 | private WaiterEntry PopWaiter() | 343 | /// </summary> |
| 344 | { | 344 | /// <returns></returns> |
| 345 | // Store the current stack head | 345 | /// In order to avoid creation and destuction of WaiterEntry |
| 346 | WaiterEntry oldFirstWaiterEntry = _headWaiterEntry._nextWaiterEntry; | 346 | /// objects each thread has its own WaiterEntry object. |
| 347 | 347 | private static WaiterEntry GetThreadWaiterEntry() | |
| 348 | // Store the new stack head | 348 | { |
| 349 | WaiterEntry newHeadWaiterEntry = oldFirstWaiterEntry._nextWaiterEntry; | 349 | if (null == CurrentWaiterEntry) |
| 350 | 350 | { | |
| 351 | // Update the old stack head list links and decrement the number | 351 | CurrentWaiterEntry = new WaiterEntry(); |
| 352 | // waiters. | 352 | } |
| 353 | RemoveWaiter(oldFirstWaiterEntry, true); | 353 | CurrentWaiterEntry.Reset(); |
| 354 | 354 | return CurrentWaiterEntry; | |
| 355 | // Update the new stack head | 355 | } |
| 356 | _headWaiterEntry._nextWaiterEntry = newHeadWaiterEntry; | 356 | |
| 357 | if (null != newHeadWaiterEntry) | 357 | #region Waiters stack methods |
| 358 | { | 358 | |
| 359 | newHeadWaiterEntry._prevWaiterEntry = _headWaiterEntry; | 359 | /// <summary> |
| 360 | } | 360 | /// Push a new waiter into the waiter's stack |
| 361 | 361 | /// </summary> | |
| 362 | // Return the old stack head | 362 | /// <param name="newWaiterEntry">A waiter to put in the stack</param> |
| 363 | return oldFirstWaiterEntry; | 363 | public void PushWaiter(WaiterEntry newWaiterEntry) |
| 364 | } | 364 | { |
| 365 | 365 | // Remove the waiter if it is already in the stack and | |
| 366 | /// <summary> | 366 | // update waiter's count as needed |
| 367 | /// Remove a waiter from the stack | 367 | RemoveWaiter(newWaiterEntry, false); |
| 368 | /// </summary> | 368 | |
| 369 | /// <param name="waiterEntry">A waiter entry to remove</param> | 369 | // If the stack is empty then newWaiterEntry is the new head of the stack |
| 370 | /// <param name="popDecrement">If true the waiter count is always decremented</param> | 370 | if (null == _headWaiterEntry._nextWaiterEntry) |
| 371 | private void RemoveWaiter(WaiterEntry waiterEntry, bool popDecrement) | 371 | { |
| 372 | { | 372 | _headWaiterEntry._nextWaiterEntry = newWaiterEntry; |
| 373 | // Store the prev entry in the list | 373 | newWaiterEntry._prevWaiterEntry = _headWaiterEntry; |
| 374 | WaiterEntry prevWaiterEntry = waiterEntry._prevWaiterEntry; | 374 | |
| 375 | 375 | } | |
| 376 | // Store the next entry in the list | 376 | // If the stack is not empty then put newWaiterEntry as the new head |
| 377 | WaiterEntry nextWaiterEntry = waiterEntry._nextWaiterEntry; | 377 | // of the stack. |
| 378 | 378 | else | |
| 379 | // A flag to indicate if we need to decrement the waiters count. | 379 | { |
| 380 | // If we got here from PopWaiter then we must decrement. | 380 | // Save the old first waiter entry |
| 381 | // If we got here from PushWaiter then we decrement only if | 381 | WaiterEntry oldFirstWaiterEntry = _headWaiterEntry._nextWaiterEntry; |
| 382 | // the waiter was already in the stack. | 382 | |
| 383 | bool decrementCounter = popDecrement; | 383 | // Update the links |
| 384 | 384 | _headWaiterEntry._nextWaiterEntry = newWaiterEntry; | |
| 385 | // Null the waiter's entry links | 385 | newWaiterEntry._nextWaiterEntry = oldFirstWaiterEntry; |
| 386 | waiterEntry._prevWaiterEntry = null; | 386 | newWaiterEntry._prevWaiterEntry = _headWaiterEntry; |
| 387 | waiterEntry._nextWaiterEntry = null; | 387 | oldFirstWaiterEntry._prevWaiterEntry = newWaiterEntry; |
| 388 | 388 | } | |
| 389 | // If the waiter entry had a prev link then update it. | 389 | |
| 390 | // It also means that the waiter is already in the list and we | 390 | // Increment the number of waiters |
| 391 | // need to decrement the waiters count. | 391 | ++_waitersCount; |
| 392 | if (null != prevWaiterEntry) | 392 | } |
| 393 | { | 393 | |
| 394 | prevWaiterEntry._nextWaiterEntry = nextWaiterEntry; | 394 | /// <summary> |
| 395 | decrementCounter = true; | 395 | /// Pop a waiter from the waiter's stack |
| 396 | } | 396 | /// </summary> |
| 397 | 397 | /// <returns>Returns the first waiter in the stack</returns> | |
| 398 | // If the waiter entry had a next link then update it. | 398 | private WaiterEntry PopWaiter() |
| 399 | // It also means that the waiter is already in the list and we | 399 | { |
| 400 | // need to decrement the waiters count. | 400 | // Store the current stack head |
| 401 | if (null != nextWaiterEntry) | 401 | WaiterEntry oldFirstWaiterEntry = _headWaiterEntry._nextWaiterEntry; |
| 402 | { | 402 | |
| 403 | nextWaiterEntry._prevWaiterEntry = prevWaiterEntry; | 403 | // Store the new stack head |
| 404 | decrementCounter = true; | 404 | WaiterEntry newHeadWaiterEntry = oldFirstWaiterEntry._nextWaiterEntry; |
| 405 | } | 405 | |
| 406 | 406 | // Update the old stack head list links and decrement the number | |
| 407 | // Decrement the waiters count if needed | 407 | // waiters. |
| 408 | if (decrementCounter) | 408 | RemoveWaiter(oldFirstWaiterEntry, true); |
| 409 | { | 409 | |
| 410 | --_waitersCount; | 410 | // Update the new stack head |
| 411 | } | 411 | _headWaiterEntry._nextWaiterEntry = newHeadWaiterEntry; |
| 412 | } | 412 | if (null != newHeadWaiterEntry) |
| 413 | 413 | { | |
| 414 | #endregion | 414 | newHeadWaiterEntry._prevWaiterEntry = _headWaiterEntry; |
| 415 | 415 | } | |
| 416 | #endregion | 416 | |
| 417 | 417 | // Return the old stack head | |
| 418 | #region WaiterEntry class | 418 | return oldFirstWaiterEntry; |
| 419 | 419 | } | |
| 420 | // A waiter entry in the _waiters queue. | 420 | |
| 421 | public class WaiterEntry : IDisposable | 421 | /// <summary> |
| 422 | { | 422 | /// Remove a waiter from the stack |
| 423 | #region Member variables | 423 | /// </summary> |
| 424 | 424 | /// <param name="waiterEntry">A waiter entry to remove</param> | |
| 425 | /// <summary> | 425 | /// <param name="popDecrement">If true the waiter count is always decremented</param> |
| 426 | /// Event to signal the waiter that it got the work item. | 426 | private void RemoveWaiter(WaiterEntry waiterEntry, bool popDecrement) |
| 427 | /// </summary> | 427 | { |
| 428 | private AutoResetEvent _waitHandle = new AutoResetEvent(false); | 428 | // Store the prev entry in the list |
| 429 | 429 | WaiterEntry prevWaiterEntry = waiterEntry._prevWaiterEntry; | |
| 430 | /// <summary> | 430 | |
| 431 | /// Flag to know if this waiter already quited from the queue | 431 | // Store the next entry in the list |
| 432 | /// because of a timeout. | 432 | WaiterEntry nextWaiterEntry = waiterEntry._nextWaiterEntry; |
| 433 | /// </summary> | 433 | |
| 434 | private bool _isTimedout = false; | 434 | // A flag to indicate if we need to decrement the waiters count. |
| 435 | 435 | // If we got here from PopWaiter then we must decrement. | |
| 436 | /// <summary> | 436 | // If we got here from PushWaiter then we decrement only if |
| 437 | /// Flag to know if the waiter was signaled and got a work item. | 437 | // the waiter was already in the stack. |
| 438 | /// </summary> | 438 | bool decrementCounter = popDecrement; |
| 439 | private bool _isSignaled = false; | 439 | |
| 440 | 440 | // Null the waiter's entry links | |
| 441 | /// <summary> | 441 | waiterEntry._prevWaiterEntry = null; |
| 442 | /// A work item that passed directly to the waiter withou going | 442 | waiterEntry._nextWaiterEntry = null; |
| 443 | /// through the queue | 443 | |
| 444 | /// </summary> | 444 | // If the waiter entry had a prev link then update it. |
| 445 | private WorkItem _workItem = null; | 445 | // It also means that the waiter is already in the list and we |
| 446 | 446 | // need to decrement the waiters count. | |
| 447 | private bool _isDisposed = false; | 447 | if (null != prevWaiterEntry) |
| 448 | 448 | { | |
| 449 | // Linked list members | 449 | prevWaiterEntry._nextWaiterEntry = nextWaiterEntry; |
| 450 | internal WaiterEntry _nextWaiterEntry = null; | 450 | decrementCounter = true; |
| 451 | internal WaiterEntry _prevWaiterEntry = null; | 451 | } |
| 452 | 452 | ||
| 453 | #endregion | 453 | // If the waiter entry had a next link then update it. |
| 454 | 454 | // It also means that the waiter is already in the list and we | |
| 455 | #region Construction | 455 | // need to decrement the waiters count. |
| 456 | 456 | if (null != nextWaiterEntry) | |
| 457 | public WaiterEntry() | 457 | { |
| 458 | { | 458 | nextWaiterEntry._prevWaiterEntry = prevWaiterEntry; |
| 459 | Reset(); | 459 | decrementCounter = true; |
| 460 | } | 460 | } |
| 461 | 461 | ||
| 462 | #endregion | 462 | // Decrement the waiters count if needed |
| 463 | 463 | if (decrementCounter) | |
| 464 | #region Public methods | 464 | { |
| 465 | 465 | --_waitersCount; | |
| 466 | public WaitHandle WaitHandle | 466 | } |
| 467 | { | 467 | } |
| 468 | get { return _waitHandle; } | 468 | |
| 469 | } | 469 | #endregion |
| 470 | 470 | ||
| 471 | public WorkItem WorkItem | 471 | #endregion |
| 472 | { | 472 | |
| 473 | get | 473 | #region WaiterEntry class |
| 474 | { | 474 | |
| 475 | lock(this) | 475 | // A waiter entry in the _waiters queue. |
| 476 | { | 476 | public sealed class WaiterEntry : IDisposable |
| 477 | return _workItem; | 477 | { |
| 478 | } | 478 | #region Member variables |
| 479 | } | 479 | |
| 480 | } | 480 | /// <summary> |
| 481 | 481 | /// Event to signal the waiter that it got the work item. | |
| 482 | /// <summary> | 482 | /// </summary> |
| 483 | /// Signal the waiter that it got a work item. | 483 | //private AutoResetEvent _waitHandle = new AutoResetEvent(false); |
| 484 | /// </summary> | 484 | private AutoResetEvent _waitHandle = EventWaitHandleFactory.CreateAutoResetEvent(); |
| 485 | /// <returns>Return true on success</returns> | 485 | |
| 486 | /// The method fails if Timeout() preceded its call | 486 | /// <summary> |
| 487 | public bool Signal(WorkItem workItem) | 487 | /// Flag to know if this waiter already quited from the queue |
| 488 | { | 488 | /// because of a timeout. |
| 489 | lock(this) | 489 | /// </summary> |
| 490 | { | 490 | private bool _isTimedout = false; |
| 491 | if (!_isTimedout) | 491 | |
| 492 | { | 492 | /// <summary> |
| 493 | _workItem = workItem; | 493 | /// Flag to know if the waiter was signaled and got a work item. |
| 494 | _isSignaled = true; | 494 | /// </summary> |
| 495 | _waitHandle.Set(); | 495 | private bool _isSignaled = false; |
| 496 | return true; | 496 | |
| 497 | } | 497 | /// <summary> |
| 498 | } | 498 | /// A work item that passed directly to the waiter withou going |
| 499 | return false; | 499 | /// through the queue |
| 500 | } | 500 | /// </summary> |
| 501 | 501 | private WorkItem _workItem = null; | |
| 502 | /// <summary> | 502 | |
| 503 | /// Mark the wait entry that it has been timed out | 503 | private bool _isDisposed = false; |
| 504 | /// </summary> | 504 | |
| 505 | /// <returns>Return true on success</returns> | 505 | // Linked list members |
| 506 | /// The method fails if Signal() preceded its call | 506 | internal WaiterEntry _nextWaiterEntry = null; |
| 507 | public bool Timeout() | 507 | internal WaiterEntry _prevWaiterEntry = null; |
| 508 | { | 508 | |
| 509 | lock(this) | 509 | #endregion |
| 510 | { | 510 | |
| 511 | // Time out can happen only if the waiter wasn't marked as | 511 | #region Construction |
| 512 | // signaled | 512 | |
| 513 | if (!_isSignaled) | 513 | public WaiterEntry() |
| 514 | { | 514 | { |
| 515 | // We don't remove the waiter from the queue, the DequeueWorkItem | 515 | Reset(); |
| 516 | // method skips _waiters that were timed out. | 516 | } |
| 517 | _isTimedout = true; | 517 | |
| 518 | return true; | 518 | #endregion |
| 519 | } | 519 | |
| 520 | } | 520 | #region Public methods |
| 521 | return false; | 521 | |
| 522 | } | 522 | public WaitHandle WaitHandle |
| 523 | 523 | { | |
| 524 | /// <summary> | 524 | get { return _waitHandle; } |
| 525 | /// Reset the wait entry so it can be used again | 525 | } |
| 526 | /// </summary> | 526 | |
| 527 | public void Reset() | 527 | public WorkItem WorkItem |
| 528 | { | 528 | { |
| 529 | _workItem = null; | 529 | get |
| 530 | _isTimedout = false; | 530 | { |
| 531 | _isSignaled = false; | 531 | return _workItem; |
| 532 | _waitHandle.Reset(); | 532 | } |
| 533 | } | 533 | } |
| 534 | 534 | ||
| 535 | /// <summary> | 535 | /// <summary> |
| 536 | /// Free resources | 536 | /// Signal the waiter that it got a work item. |
| 537 | /// </summary> | 537 | /// </summary> |
| 538 | public void Close() | 538 | /// <returns>Return true on success</returns> |
| 539 | { | 539 | /// The method fails if Timeout() preceded its call |
| 540 | if (null != _waitHandle) | 540 | public bool Signal(WorkItem workItem) |
| 541 | { | 541 | { |
| 542 | _waitHandle.Close(); | 542 | lock(this) |
| 543 | _waitHandle = null; | 543 | { |
| 544 | } | 544 | if (!_isTimedout) |
| 545 | } | 545 | { |
| 546 | 546 | _workItem = workItem; | |
| 547 | #endregion | 547 | _isSignaled = true; |
| 548 | 548 | _waitHandle.Set(); | |
| 549 | #region IDisposable Members | 549 | return true; |
| 550 | 550 | } | |
| 551 | public void Dispose() | 551 | } |
| 552 | { | 552 | return false; |
| 553 | if (!_isDisposed) | 553 | } |
| 554 | { | 554 | |
| 555 | Close(); | 555 | /// <summary> |
| 556 | _isDisposed = true; | 556 | /// Mark the wait entry that it has been timed out |
| 557 | } | 557 | /// </summary> |
| 558 | } | 558 | /// <returns>Return true on success</returns> |
| 559 | 559 | /// The method fails if Signal() preceded its call | |
| 560 | ~WaiterEntry() | 560 | public bool Timeout() |
| 561 | { | 561 | { |
| 562 | Dispose(); | 562 | lock(this) |
| 563 | } | 563 | { |
| 564 | 564 | // Time out can happen only if the waiter wasn't marked as | |
| 565 | #endregion | 565 | // signaled |
| 566 | } | 566 | if (!_isSignaled) |
| 567 | 567 | { | |
| 568 | #endregion | 568 | // We don't remove the waiter from the queue, the DequeueWorkItem |
| 569 | 569 | // method skips _waiters that were timed out. | |
| 570 | #region IDisposable Members | 570 | _isTimedout = true; |
| 571 | 571 | return true; | |
| 572 | public void Dispose() | 572 | } |
| 573 | { | 573 | } |
| 574 | if (!_isDisposed) | 574 | return false; |
| 575 | { | 575 | } |
| 576 | Cleanup(); | 576 | |
| 577 | _isDisposed = true; | 577 | /// <summary> |
| 578 | GC.SuppressFinalize(this); | 578 | /// Reset the wait entry so it can be used again |
| 579 | } | 579 | /// </summary> |
| 580 | } | 580 | public void Reset() |
| 581 | 581 | { | |
| 582 | ~WorkItemsQueue() | 582 | _workItem = null; |
| 583 | { | 583 | _isTimedout = false; |
| 584 | Cleanup(); | 584 | _isSignaled = false; |
| 585 | } | 585 | _waitHandle.Reset(); |
| 586 | 586 | } | |
| 587 | private void ValidateNotDisposed() | 587 | |
| 588 | { | 588 | /// <summary> |
| 589 | if(_isDisposed) | 589 | /// Free resources |
| 590 | { | 590 | /// </summary> |
| 591 | throw new ObjectDisposedException(GetType().ToString(), "The SmartThreadPool has been shutdown"); | 591 | public void Close() |
| 592 | } | 592 | { |
| 593 | } | 593 | if (null != _waitHandle) |
| 594 | 594 | { | |
| 595 | #endregion | 595 | _waitHandle.Close(); |
| 596 | } | 596 | _waitHandle = null; |
| 597 | 597 | } | |
| 598 | #endregion | 598 | } |
| 599 | } | 599 | |
| 600 | 600 | #endregion | |
| 601 | |||
| 602 | #region IDisposable Members | ||
| 603 | |||
| 604 | public void Dispose() | ||
| 605 | { | ||
| 606 | lock (this) | ||
| 607 | { | ||
| 608 | if (!_isDisposed) | ||
| 609 | { | ||
| 610 | Close(); | ||
| 611 | } | ||
| 612 | _isDisposed = true; | ||
| 613 | } | ||
| 614 | } | ||
| 615 | |||
| 616 | #endregion | ||
| 617 | } | ||
| 618 | |||
| 619 | #endregion | ||
| 620 | |||
| 621 | #region IDisposable Members | ||
| 622 | |||
| 623 | public void Dispose() | ||
| 624 | { | ||
| 625 | if (!_isDisposed) | ||
| 626 | { | ||
| 627 | Cleanup(); | ||
| 628 | } | ||
| 629 | _isDisposed = true; | ||
| 630 | } | ||
| 631 | |||
| 632 | private void ValidateNotDisposed() | ||
| 633 | { | ||
| 634 | if(_isDisposed) | ||
| 635 | { | ||
| 636 | throw new ObjectDisposedException(GetType().ToString(), "The SmartThreadPool has been shutdown"); | ||
| 637 | } | ||
| 638 | } | ||
| 639 | |||
| 640 | #endregion | ||
| 641 | } | ||
| 642 | |||
| 643 | #endregion | ||
| 644 | } | ||
| 645 | |||