src/mem/ruby/eventqueue/RubyEventQueue.hh

   1
   2 /*
   3  * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met: redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer;
  10  * redistributions in binary form must reproduce the above copyright
  11  * notice, this list of conditions and the following disclaimer in the
  12  * documentation and/or other materials provided with the distribution;
  13  * neither the name of the copyright holders nor the names of its
  14  * contributors may be used to endorse or promote products derived from
  15  * this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  20  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  21  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  22  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  23  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 /*
  31  * $Id$
  32  *
  33  * Description: The EventQueue class implements an event queue which
  34  * can be trigger events, allowing our simulation to be event driven.
  35  *
  36  * Currently, the only event we support is a Consumer being signaled
  37  * by calling the consumer's wakeup() routine.  Adding the event to
  38  * the queue does not require a virtual function call, though calling
  39  * wakeup() is a virtual function call.
  40  *
  41  * The method triggerEvents() is called with a global time.  All
  42  * events which are before or at this time are triggered in timestamp
  43  * order.  No ordering is enforced for events scheduled to occur at
  44  * the same time.  Events scheduled to wakeup the same consumer at the
  45  * same time are combined into a single event.
  46  *
  47  * The method scheduleConsumerWakeup() is called with a global time
  48  * and a consumer pointer.  The event queue will call the wakeup()
  49  * method of the consumer at the appropriate time.
  50  *
  51  * This implementation of EventQueue uses a dynamically sized array
  52  * managed as a heap.  The algorithms used has O(lg n) for insert and
  53  * O(lg n) for extract minimum element. (Based on chapter 7 of Cormen,
  54  * Leiserson, and Rivest.)  The array is dynamically sized and is
  55  * automatically doubled in size when necessary.
  56  *
  57  */
  58
  59 #ifndef RUBYEVENTQUEUE_H
  60 #define RUBYEVENTQUEUE_H
  61
  62 #include "config/no_vector_bounds_checks.hh"
  63 #include "mem/ruby/common/Global.hh"
  64 #include "mem/gems_common/Vector.hh"
  65
  66 class Consumer;
  67 template <class TYPE> class PrioHeap;
  68 class RubyEventQueueNode;
  69
  70 class RubyEventQueue {
  71 public:
  72   // Constructors
  73   RubyEventQueue();
  74
  75   // Destructor
  76   ~RubyEventQueue();
  77
  78   // Public Methods
  79
  80   Time getTime() const { return m_globalTime; }
  81   void scheduleEvent(Consumer* consumer, Time timeDelta) { scheduleEventAbsolute(consumer, timeDelta + m_globalTime); }
  82   void scheduleEventAbsolute(Consumer* consumer, Time timeAbs);
  83   void triggerEvents(Time t); // called to handle all events <= time t
  84   void triggerAllEvents();
  85   void print(ostream& out) const;
  86   bool isEmpty() const;
  87
  88   Time getTimeOfLastRecovery() {return m_timeOfLastRecovery;}
  89   void setTimeOfLastRecovery(Time t) {m_timeOfLastRecovery = t;}
  90
  91   // Private Methods
  92 private:
  93   // Private copy constructor and assignment operator
  94   void init();
  95   RubyEventQueue(const RubyEventQueue& obj);
  96   RubyEventQueue& operator=(const RubyEventQueue& obj);
  97
  98   // Data Members (m_ prefix)
  99   PrioHeap<RubyEventQueueNode>* m_prio_heap_ptr;
 100   Time m_globalTime;
 101   Time m_timeOfLastRecovery;
 102 };
 103
 104 // Output operator declaration
 105 inline extern
 106 ostream& operator<<(ostream& out, const RubyEventQueue& obj);
 107
 108 // ******************* Definitions *******************
 109
 110 // Output operator definition
 111 inline extern
 112 ostream& operator<<(ostream& out, const RubyEventQueue& obj)
 113 {
 114   obj.print(out);
 115   out << flush;
 116   return out;
 117 }
 118
 119 #endif //EVENTQUEUE_H