decode_packet_trace.py revision 9617:c503acb59e51 
1#!/usr/bin/env python
2
3# Copyright (c) 2013 ARM Limited
4# All rights reserved
5#
6# The license below extends only to copyright in the software and shall
7# not be construed as granting a license to any other intellectual
8# property including but not limited to intellectual property relating
9# to a hardware implementation of the functionality of the software
10# licensed hereunder.  You may use the software subject to the license
11# terms below provided that you ensure that this notice is replicated
12# unmodified and in its entirety in all distributions of the software,
13# modified or unmodified, in source code or in binary form.
14#
15# Redistribution and use in source and binary forms, with or without
16# modification, are permitted provided that the following conditions are
17# met: redistributions of source code must retain the above copyright
18# notice, this list of conditions and the following disclaimer;
19# redistributions in binary form must reproduce the above copyright
20# notice, this list of conditions and the following disclaimer in the
21# documentation and/or other materials provided with the distribution;
22# neither the name of the copyright holders nor the names of its
23# contributors may be used to endorse or promote products derived from
24# this software without specific prior written permission.
25#
26# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
27# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
28# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
29# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
30# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
31# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
32# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
36# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37#
38# Copyright 2008 Google Inc.  All rights reserved.
39# http://code.google.com/p/protobuf/
40#
41# Redistribution and use in source and binary forms, with or without
42# modification, are permitted provided that the following conditions are
43# met:
44#
45#     * Redistributions of source code must retain the above copyright
46# notice, this list of conditions and the following disclaimer.
47#     * Redistributions in binary form must reproduce the above
48# copyright notice, this list of conditions and the following disclaimer
49# in the documentation and/or other materials provided with the
50# distribution.
51#     * Neither the name of Google Inc. nor the names of its
52# contributors may be used to endorse or promote products derived from
53# this software without specific prior written permission.
54#
55# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
56# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
57# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
58# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
59# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
60# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
61# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
62# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
63# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
64# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
65# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
66#
67# Authors: Andreas Hansson
68#
69
70# This script is used to dump protobuf packet traces to ASCII
71# format. It assumes that protoc has been executed and already
72# generated the Python package for the packet messages. This can
73# be done manually using:
74# protoc --python_out=. --proto_path=src/proto src/proto/packet.proto
75#
76# The ASCII trace format uses one line per request on the format cmd,
77# addr, size, tick,flags. For example:
78# r,128,64,4000,0
79# w,232123,64,500000,0
80
81import struct
82import sys
83import packet_pb2
84
85def DecodeVarint(in_file):
86    """
87    The decoding of the Varint32 is copied from
88    google.protobuf.internal.decoder and is only repeated here to
89    avoid depending on the internal functions in the library. If the
90    end of file is reached, return (0, 0).
91    """
92    result = 0
93    shift = 0
94    pos = 0
95    # Use a 32-bit mask
96    mask = 0xffffffff
97    while 1:
98        c = in_file.read(1)
99        if len(c) == 0:
100            return (0, 0)
101        b = struct.unpack('<B', c)[0]
102        result |= ((b & 0x7f) << shift)
103        pos += 1
104        if not (b & 0x80):
105            if result > 0x7fffffffffffffff:
106                result -= (1 << 64)
107                result |= ~mask
108            else:
109                result &= mask
110                return (result, pos)
111            shift += 7
112            if shift >= 64:
113                raise IOError('Too many bytes when decoding varint.')
114
115def decodeMessage(in_file, message):
116    """
117    Attempt to read a message from the file and decode it. Return
118    False if no message could be read.
119    """
120    try:
121        size, pos = DecodeVarint(in_file)
122        if size == 0:
123            return False
124        buf = in_file.read(size)
125        message.ParseFromString(buf)
126        return True
127    except IOError:
128        return False
129
130def main():
131    if len(sys.argv) != 3:
132        print "Usage: ", sys.argv[0], " <protobuf input> <ASCII output>"
133        exit(-1)
134
135    try:
136       proto_in = open(sys.argv[1], 'rb')
137    except IOError:
138        print "Failed to open ", sys.argv[1], " for reading"
139        exit(-1)
140
141    try:
142        ascii_out = open(sys.argv[2], 'w')
143    except IOError:
144        print "Failed to open ", sys.argv[2], " for writing"
145        exit(-1)
146
147    # Read the magic number in 4-byte Little Endian
148    magic_number = proto_in.read(4)
149
150    if magic_number != "gem5":
151        print "Unrecognized file"
152        exit(-1)
153
154    print "Parsing packet header"
155
156    # Add the packet header
157    header = packet_pb2.PacketHeader()
158    decodeMessage(proto_in, header)
159
160    print "Object id:", header.obj_id
161    print "Tick frequency:", header.tick_freq
162
163    print "Parsing packets"
164
165    num_packets = 0
166    ignored_flags = False
167    packet = packet_pb2.Packet()
168
169    # Decode the packet messages until we hit the end of the file
170    while decodeMessage(proto_in, packet):
171        num_packets += 1
172        # ReadReq is 1 and WriteReq is 4 in src/mem/packet.hh Command enum
173        cmd = 'r' if packet.cmd == 1 else ('w' if packet.cmd == 4 else 'u')
174        if packet.HasField('flags'):
175            # Currently not printing flags
176            ignored_flags = True
177        ascii_out.write('%s,%s,%s,%s\n' % (cmd, packet.addr, packet.size,
178                                           packet.tick))
179
180    print "Parsed packets:", num_packets
181    if ignored_flags:
182        print "Encountered packet flags that were ignored"
183
184    # We're done
185    ascii_out.close()
186    proto_in.close()
187
188if __name__ == "__main__":
189    main()
190