write_queue_entry.hh revision 12724:4f6fac3191d2 
1/*
2 * Copyright (c) 2012-2013, 2015-2016 ARM Limited
3 * All rights reserved.
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2002-2005 The Regents of The University of Michigan
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions are
19 * met: redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer;
21 * redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution;
24 * neither the name of the copyright holders nor the names of its
25 * contributors may be used to endorse or promote products derived from
26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Erik Hallnor
41 *          Andreas Hansson
42 */
43
44/**
45 * @file
46 * Write queue entry
47 */
48
49#ifndef __MEM_CACHE_WRITE_QUEUE_ENTRY_HH__
50#define __MEM_CACHE_WRITE_QUEUE_ENTRY_HH__
51
52#include <list>
53
54#include "base/printable.hh"
55#include "mem/cache/queue_entry.hh"
56
57class BaseCache;
58
59/**
60 * Write queue entry
61 */
62class WriteQueueEntry : public QueueEntry, public Printable
63{
64
65    /**
66     * Consider the queues friends to avoid making everything public.
67     */
68    template<typename Entry>
69    friend class Queue;
70    friend class WriteQueue;
71
72  public:
73
74    class Target {
75      public:
76
77        const Tick recvTime;  //!< Time when request was received (for stats)
78        const Tick readyTime; //!< Time when request is ready to be serviced
79        const Counter order;  //!< Global order (for memory consistency mgmt)
80        const PacketPtr pkt;  //!< Pending request packet.
81
82        Target(PacketPtr _pkt, Tick _readyTime, Counter _order)
83            : recvTime(curTick()), readyTime(_readyTime), order(_order),
84              pkt(_pkt)
85        {}
86    };
87
88    class TargetList : public std::list<Target> {
89
90      public:
91
92        TargetList() {}
93        void add(PacketPtr pkt, Tick readyTime, Counter order);
94        bool checkFunctional(PacketPtr pkt);
95        void print(std::ostream &os, int verbosity,
96                   const std::string &prefix) const;
97    };
98
99    /** A list of write queue entriess. */
100    typedef std::list<WriteQueueEntry *> List;
101    /** WriteQueueEntry list iterator. */
102    typedef List::iterator Iterator;
103
104    bool sendPacket(BaseCache &cache);
105
106  private:
107
108    /**
109     * Pointer to this entry on the ready list.
110     * @sa MissQueue, WriteQueue::readyList
111     */
112    Iterator readyIter;
113
114    /**
115     * Pointer to this entry on the allocated list.
116     * @sa MissQueue, WriteQueue::allocatedList
117     */
118    Iterator allocIter;
119
120    /** List of all requests that match the address */
121    TargetList targets;
122
123  public:
124
125    /** A simple constructor. */
126    WriteQueueEntry() {}
127
128    /**
129     * Allocate a miss to this entry.
130     * @param blk_addr The address of the block.
131     * @param blk_size The number of bytes to request.
132     * @param pkt The original write.
133     * @param when_ready When should the write be sent out.
134     * @param _order The logical order of this write.
135     */
136    void allocate(Addr blk_addr, unsigned blk_size, PacketPtr pkt,
137                  Tick when_ready, Counter _order);
138
139
140    /**
141     * Mark this entry as free.
142     */
143    void deallocate();
144
145    /**
146     * Returns the current number of allocated targets.
147     * @return The current number of allocated targets.
148     */
149    int getNumTargets() const
150    { return targets.size(); }
151
152    /**
153     * Returns true if there are targets left.
154     * @return true if there are targets
155     */
156    bool hasTargets() const { return !targets.empty(); }
157
158    /**
159     * Returns a reference to the first target.
160     * @return A pointer to the first target.
161     */
162    Target *getTarget()
163    {
164        assert(hasTargets());
165        return &targets.front();
166    }
167
168    /**
169     * Pop first target.
170     */
171    void popTarget()
172    {
173        targets.pop_front();
174    }
175
176    bool checkFunctional(PacketPtr pkt);
177
178    /**
179     * Prints the contents of this MSHR for debugging.
180     */
181    void print(std::ostream &os,
182               int verbosity = 0,
183               const std::string &prefix = "") const;
184    /**
185     * A no-args wrapper of print(std::ostream...)  meant to be
186     * invoked from DPRINTFs avoiding string overheads in fast mode
187     *
188     * @return string with mshr fields
189     */
190    std::string print() const;
191};
192
193#endif // __MEM_CACHE_WRITE_QUEUE_ENTRY_HH__
194