trace_gen.hh revision 12811 
1/*
2 * Copyright (c) 2012-2013, 2017-2018 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 here under.  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 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Thomas Grass
38 *          Andreas Hansson
39 *          Sascha Bischoff
40 *          Neha Agarwal
41 */
42
43/**
44 * @file
45 * Declaration of the trace generator that reads a trace file
46 * and plays the transactions.
47 */
48
49#ifndef __CPU_TRAFFIC_GEN_TRACE_GEN_HH__
50#define __CPU_TRAFFIC_GEN_TRACE_GEN_HH__
51
52#include "base/bitfield.hh"
53#include "base/intmath.hh"
54#include "base_gen.hh"
55#include "mem/packet.hh"
56#include "proto/protoio.hh"
57
58/**
59 * The trace replay generator reads a trace file and plays
60 * back the transactions. The trace is offset with respect to
61 * the time when the state was entered.
62 */
63class TraceGen : public BaseGen
64{
65
66  private:
67
68    /**
69     * This struct stores a line in the trace file.
70     */
71    struct TraceElement {
72
73        /** Specifies if the request is to be a read or a write */
74        MemCmd cmd;
75
76        /** The address for the request */
77        Addr addr;
78
79        /** The size of the access for the request */
80        Addr blocksize;
81
82        /** The time at which the request should be sent */
83        Tick tick;
84
85        /** Potential request flags to use */
86        Request::FlagsType flags;
87
88        /**
89         * Check validity of this element.
90         *
91         * @return if this element is valid
92         */
93        bool isValid() const {
94            return cmd != MemCmd::InvalidCmd;
95        }
96
97        /**
98         * Make this element invalid.
99         */
100        void clear() {
101            cmd = MemCmd::InvalidCmd;
102        }
103    };
104
105    /**
106     * The InputStream encapsulates a trace file and the
107     * internal buffers and populates TraceElements based on
108     * the input.
109     */
110    class InputStream
111    {
112
113      private:
114
115        /// Input file stream for the protobuf trace
116        ProtoInputStream trace;
117
118      public:
119
120        /**
121         * Create a trace input stream for a given file name.
122         *
123         * @param filename Path to the file to read from
124         */
125        InputStream(const std::string& filename);
126
127        /**
128         * Reset the stream such that it can be played once
129         * again.
130         */
131        void reset();
132
133        /**
134         * Check the trace header to make sure that it is of the right
135         * format.
136         */
137        void init();
138
139        /**
140         * Attempt to read a trace element from the stream,
141         * and also notify the caller if the end of the file
142         * was reached.
143         *
144         * @param element Trace element to populate
145         * @return True if an element could be read successfully
146         */
147        bool read(TraceElement& element);
148    };
149
150  public:
151
152    /**
153     * Create a trace generator.
154     *
155     * @param gen Traffic generator owning this sequence generator
156     * @param _duration duration of this state before transitioning
157     * @param trace_file File to read the transactions from
158     * @param addr_offset Positive offset to add to trace address
159     */
160    TraceGen(BaseTrafficGen &gen, Tick _duration,
161             const std::string& trace_file, Addr addr_offset)
162        : BaseGen(gen, _duration),
163          trace(trace_file),
164          tickOffset(0),
165          addrOffset(addr_offset),
166          traceComplete(false)
167    {
168    }
169
170    void enter();
171
172    PacketPtr getNextPacket();
173
174    void exit();
175
176    /**
177     * Returns the tick when the next request should be generated. If
178     * the end of the file has been reached, it returns MaxTick to
179     * indicate that there will be no more requests.
180     */
181    Tick nextPacketTick(bool elastic, Tick delay) const;
182
183  private:
184
185    /** Input stream used for reading the input trace file */
186    InputStream trace;
187
188    /** Store the current and next element in the trace */
189    TraceElement currElement;
190    TraceElement nextElement;
191
192    /**
193     * Stores the time when the state was entered. This is to add an
194     * offset to the times stored in the trace file. This is mutable
195     * to allow us to change it as part of nextPacketTick.
196     */
197    mutable Tick tickOffset;
198
199    /**
200     * Offset for memory requests. Used to shift the trace
201     * away from the CPU address space.
202     */
203    Addr addrOffset;
204
205    /**
206     * Set to true when the trace replay for one instance of
207     * state is complete.
208     */
209    bool traceComplete;
210};
211
212#endif
213