mcs/class/System.Core/System.Linq/ParallelExecuter.cs

   1 #if NET_4_0
   2 //
   3 // ParallelExecuter.cs
   4 //
   5 // Author:
   6 //       Jérémie "Garuma" Laval <jeremie.laval@gmail.com>
   7 //
   8 // Copyright (c) 2010 Jérémie "Garuma" Laval
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining a copy
  11 // of this software and associated documentation files (the "Software"), to deal
  12 // in the Software without restriction, including without limitation the rights
  13 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14 // copies of the Software, and to permit persons to whom the Software is
  15 // furnished to do so, subject to the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be included in
  18 // all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  23 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  26 // THE SOFTWARE.
  27
  28 using System;
  29 using System.Threading;
  30 using System.Threading.Tasks;
  31 using System.Collections;
  32 using System.Collections.Generic;
  33 using System.Collections.Concurrent;
  34
  35 namespace System.Linq
  36 {
  37         // TODO: Refactory each of the Process method into one big entity
  38         // Check CancellationToken.Canceled parameter in the Task's action body too
  39         internal static class ParallelExecuter
  40         {
  41                 internal static QueryOptions CheckQuery<T> (QueryBaseNode<T> startingNode)
  42                 {
  43                         return CheckQuery<T> (startingNode, false);
  44                 }
  45
  46                 internal static QueryOptions CheckQuery<T> (QueryBaseNode<T> startingNode, bool blocking)
  47                 {
  48                         return CheckQuery (startingNode, GetBestWorkerNumber (blocking));
  49                 }
  50
  51                 internal static QueryOptions CheckQuery<T> (QueryBaseNode<T> startingNode, int partitionCount)
  52                 {
  53                         QueryCheckerVisitor visitor = new QueryCheckerVisitor (partitionCount);
  54                         startingNode.Visit (visitor);
  55
  56                         return visitor.Options;
  57                 }
  58
  59                 // QueryOptions.ImplementerToken = QueryOptions.ImplementerToken.Chain (myOperatorSource);
  60                 internal static CancellationToken Chain (this CancellationToken self, CancellationTokenSource other)
  61                 {
  62                         CancellationTokenSource linked = CancellationTokenSource.CreateLinkedTokenSource (self, other.Token);
  63                         return linked.Token;
  64                 }
  65
  66                 internal static int GetBestWorkerNumber ()
  67                 {
  68                         return GetBestWorkerNumber (false);
  69                 }
  70
  71                 internal static int GetBestWorkerNumber (bool blocking)
  72                 {
  73                         return blocking ? Environment.ProcessorCount + 1 : Environment.ProcessorCount;
  74                 }
  75
  76                 internal static Task[] Process<TSource, TElement> (QueryBaseNode<TSource> node, Action<TElement> call,
  77                                                                    Func<QueryBaseNode<TSource>, QueryOptions, IList<IEnumerable<TElement>>> acquisitionFunc,
  78                                                                    QueryOptions options)
  79                 {
  80                         return Process<TSource, TElement> (node, call, acquisitionFunc, null, options);
  81                 }
  82
  83                 internal static Task[] Process<TSource, TElement> (QueryBaseNode<TSource> node, Action<TElement> call,
  84                                                                    Func<QueryBaseNode<TSource>, QueryOptions, IList<IEnumerable<TElement>>> acquisitionFunc,
  85                                                                    Action endAction,
  86                                                                    QueryOptions options)
  87                 {
  88                         return Process<TSource, TElement> (node,
  89                                                            (e, i) => call (e),
  90                                                            acquisitionFunc,
  91                                                            endAction == null ? ((Action<int>)null) : (i) => endAction (),
  92                                                            options);
  93                 }
  94
  95                 internal static Task[] Process<TSource, TElement> (QueryBaseNode<TSource> node, Action<TElement, int> call,
  96                                                                    Func<QueryBaseNode<TSource>, QueryOptions, IList<IEnumerable<TElement>>> acquisitionFunc,
  97                                                                    Action<int> endAction,
  98                                                                    QueryOptions options)
  99                 {
 100                         IList<IEnumerable<TElement>> enumerables = acquisitionFunc (node, options);
 101
 102                         Task[] tasks = new Task[enumerables.Count];
 103
 104                         for (int i = 0; i < tasks.Length; i++) {
 105                                 int index = i;
 106                                 tasks[i] = Task.Factory.StartNew (() => {
 107                                         foreach (TElement item in enumerables[index]) {
 108                                                 // This is from specific operators
 109                                                 if (options.ImplementerToken.IsCancellationRequested)
 110                                                         break;
 111                                                 if (options.Token.IsCancellationRequested)
 112                                                         throw new OperationCanceledException (options.Token);
 113
 114                                                 call (item, index);
 115                                         }
 116                                         if (endAction != null)
 117                                                 endAction (index);
 118                                   }, options.Token);
 119                         }
 120
 121                         return tasks;
 122                 }
 123
 124                 internal static void ProcessAndBlock<T> (QueryBaseNode<T> node, Action<T> call)
 125                 {
 126                         QueryOptions options = CheckQuery (node, true);
 127
 128                         Task[] tasks = Process (node, call, (n, o) => n.GetEnumerables (o), options);
 129                         Task.WaitAll (tasks, options.Token);
 130                 }
 131
 132                 internal static Action ProcessAndCallback<T> (QueryBaseNode<T> node, Action<T> call,
 133                                                               Action callback, QueryOptions options)
 134                 {
 135                         Task[] tasks = Process (node, call, (n, o) => n.GetEnumerables (o), options);
 136                         if (callback != null)
 137                                 Task.Factory.ContinueWhenAll (tasks,  (_) => callback ());
 138
 139                         return () => Task.WaitAll (tasks, options.Token);
 140                 }
 141
 142                 internal static Action ProcessAndCallback<T> (QueryBaseNode<T> node, Action<KeyValuePair<long, T>, int> call,
 143                                                               Action callback, QueryOptions options)
 144                 {
 145                         return ProcessAndCallback<T> (node, call, null, callback, options);
 146                 }
 147
 148                 internal static Action ProcessAndCallback<T> (QueryBaseNode<T> node, Action<KeyValuePair<long, T>, int> call,
 149                                                               Action<int> endAction,
 150                                                               Action callback, QueryOptions options)
 151                 {
 152                         Task[] tasks = Process (node, call, (n, o) => n.GetOrderedEnumerables (o), endAction, options);
 153                         if (callback != null)
 154                                 Task.Factory.ContinueWhenAll (tasks,  (_) => callback ());
 155
 156                         return () => Task.WaitAll (tasks, options.Token);
 157                 }
 158
 159                 internal static void ProcessAndAggregate<T, U> (QueryBaseNode<T> node,
 160                                                     Func<U> seedFunc,
 161                                                     Func<U, T, U> localCall,
 162                                                     Action<IList<U>> call)
 163                 {
 164                         QueryOptions options = CheckQuery (node, true);
 165
 166                         IList<IEnumerable<T>> enumerables = node.GetEnumerables (options);
 167                         U[] locals = new U[enumerables.Count];
 168                         Task[] tasks = new Task[enumerables.Count];
 169
 170                         bool init = false;
 171                         if (seedFunc != null) {
 172                                 for (int i = 0; i < locals.Length; i++)
 173                                         locals[i] = seedFunc ();
 174                                 init = true;
 175                         }
 176
 177                         for (int i = 0; i < tasks.Length; i++) {
 178                                 int index = i;
 179                                 tasks[i] = Task.Factory.StartNew (() => {
 180                                         foreach (T item in enumerables[index]) {
 181                                                 // This is from specific operators
 182                                                 if (options.ImplementerToken.IsCancellationRequested)
 183                                                         break;
 184                                                 if (options.Token.IsCancellationRequested)
 185                                                         throw new OperationCanceledException (options.Token);
 186
 187                                                 if (!init) {
 188                                                         init = true;
 189                                                         // HACK: TODO: omfwtfitsomuchsucks
 190                                                         locals[index] = (U)(object)item;
 191                                                         continue;
 192                                                 }
 193
 194                                                 U acc = locals[index];
 195                                                 locals[index] = localCall (acc, item);
 196                                         }
 197                                 }, options.Token);
 198                         }
 199
 200                         Task.WaitAll (tasks, options.Token);
 201
 202                         if (call != null)
 203                                 call (locals);
 204                 }
 205         }
 206 }
 207 #endif