etherlink.cc revision 2665 
1/*
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Nathan Binkert
29 *          Ron Dreslinski
30 */
31
32/* @file
33 * Device module for modelling a fixed bandwidth full duplex ethernet link
34 */
35
36#include <cmath>
37#include <deque>
38#include <string>
39#include <vector>
40
41#include "base/random.hh"
42#include "base/trace.hh"
43#include "dev/etherdump.hh"
44#include "dev/etherint.hh"
45#include "dev/etherlink.hh"
46#include "dev/etherpkt.hh"
47#include "sim/builder.hh"
48#include "sim/serialize.hh"
49#include "sim/system.hh"
50#include "sim/root.hh"
51
52using namespace std;
53
54EtherLink::EtherLink(const string &name, EtherInt *peer0, EtherInt *peer1,
55                     double rate, Tick delay, Tick delayVar, EtherDump *dump)
56    : SimObject(name)
57{
58    link[0] = new Link(name + ".link0", this, 0, rate, delay, delayVar, dump);
59    link[1] = new Link(name + ".link1", this, 1, rate, delay, delayVar, dump);
60
61    interface[0] = new Interface(name + ".int0", link[0], link[1]);
62    interface[1] = new Interface(name + ".int1", link[1], link[0]);
63
64    interface[0]->setPeer(peer0);
65    peer0->setPeer(interface[0]);
66    interface[1]->setPeer(peer1);
67    peer1->setPeer(interface[1]);
68}
69
70EtherLink::~EtherLink()
71{
72    delete link[0];
73    delete link[1];
74
75    delete interface[0];
76    delete interface[1];
77}
78
79EtherLink::Interface::Interface(const string &name, Link *tx, Link *rx)
80    : EtherInt(name), txlink(tx)
81{
82    tx->setTxInt(this);
83    rx->setRxInt(this);
84}
85
86EtherLink::Link::Link(const string &name, EtherLink *p, int num,
87                      double rate, Tick delay, Tick delay_var, EtherDump *d)
88    : objName(name), parent(p), number(num), txint(NULL), rxint(NULL),
89      ticksPerByte(rate), linkDelay(delay), delayVar(delay_var), dump(d),
90      doneEvent(this)
91{ }
92
93void
94EtherLink::serialize(ostream &os)
95{
96    link[0]->serialize("link0", os);
97    link[1]->serialize("link1", os);
98}
99
100void
101EtherLink::unserialize(Checkpoint *cp, const string &section)
102{
103    link[0]->unserialize("link0", cp, section);
104    link[1]->unserialize("link1", cp, section);
105}
106
107void
108EtherLink::Link::txComplete(EthPacketPtr packet)
109{
110    DPRINTF(Ethernet, "packet received: len=%d\n", packet->length);
111    DDUMP(EthernetData, packet->data, packet->length);
112    rxint->sendPacket(packet);
113}
114
115class LinkDelayEvent : public Event
116{
117  protected:
118    EtherLink::Link *link;
119    EthPacketPtr packet;
120
121  public:
122    // non-scheduling version for createForUnserialize()
123    LinkDelayEvent();
124    LinkDelayEvent(EtherLink::Link *link, EthPacketPtr pkt, Tick when);
125
126    void process();
127
128    virtual void serialize(ostream &os);
129    virtual void unserialize(Checkpoint *cp, const string &section);
130    static Serializable *createForUnserialize(Checkpoint *cp,
131                                              const string &section);
132};
133
134void
135EtherLink::Link::txDone()
136{
137    if (dump)
138        dump->dump(packet);
139
140    if (linkDelay > 0) {
141        DPRINTF(Ethernet, "packet delayed: delay=%d\n", linkDelay);
142        new LinkDelayEvent(this, packet, curTick + linkDelay);
143    } else {
144        txComplete(packet);
145    }
146
147    packet = 0;
148    assert(!busy());
149
150    txint->sendDone();
151}
152
153bool
154EtherLink::Link::transmit(EthPacketPtr pkt)
155{
156    if (busy()) {
157        DPRINTF(Ethernet, "packet not sent, link busy\n");
158        return false;
159    }
160
161    DPRINTF(Ethernet, "packet sent: len=%d\n", pkt->length);
162    DDUMP(EthernetData, pkt->data, pkt->length);
163
164    packet = pkt;
165    Tick delay = (Tick)ceil(((double)pkt->length * ticksPerByte) + 1.0);
166    if (delayVar != 0) {
167        Random<Tick> var;
168        delay +=  var.uniform(0, delayVar);
169    }
170    DPRINTF(Ethernet, "scheduling packet: delay=%d, (rate=%f)\n",
171            delay, ticksPerByte);
172    doneEvent.schedule(curTick + delay);
173
174    return true;
175}
176
177void
178EtherLink::Link::serialize(const string &base, ostream &os)
179{
180    bool packet_exists = packet;
181    paramOut(os, base + ".packet_exists", packet_exists);
182    if (packet_exists)
183        packet->serialize(base + ".packet", os);
184
185    bool event_scheduled = doneEvent.scheduled();
186    paramOut(os, base + ".event_scheduled", event_scheduled);
187    if (event_scheduled) {
188        Tick event_time = doneEvent.when();
189        paramOut(os, base + ".event_time", event_time);
190    }
191
192}
193
194void
195EtherLink::Link::unserialize(const string &base, Checkpoint *cp,
196                             const string &section)
197{
198    bool packet_exists;
199    paramIn(cp, section, base + ".packet_exists", packet_exists);
200    if (packet_exists) {
201        packet = new EthPacketData(16384);
202        packet->unserialize(base + ".packet", cp, section);
203    }
204
205    bool event_scheduled;
206    paramIn(cp, section, base + ".event_scheduled", event_scheduled);
207    if (event_scheduled) {
208        Tick event_time;
209        paramIn(cp, section, base + ".event_time", event_time);
210        doneEvent.schedule(event_time);
211    }
212}
213
214LinkDelayEvent::LinkDelayEvent()
215    : Event(&mainEventQueue), link(NULL)
216{
217    setFlags(AutoSerialize);
218    setFlags(AutoDelete);
219}
220
221LinkDelayEvent::LinkDelayEvent(EtherLink::Link *l, EthPacketPtr p, Tick when)
222    : Event(&mainEventQueue), link(l), packet(p)
223{
224    setFlags(AutoSerialize);
225    setFlags(AutoDelete);
226    schedule(when);
227}
228
229void
230LinkDelayEvent::process()
231{
232    link->txComplete(packet);
233}
234
235void
236LinkDelayEvent::serialize(ostream &os)
237{
238    paramOut(os, "type", string("LinkDelayEvent"));
239    Event::serialize(os);
240
241    EtherLink *parent = link->parent;
242    bool number = link->number;
243    SERIALIZE_OBJPTR(parent);
244    SERIALIZE_SCALAR(number);
245
246    packet->serialize("packet", os);
247}
248
249
250void
251LinkDelayEvent::unserialize(Checkpoint *cp, const string &section)
252{
253    Event::unserialize(cp, section);
254
255    EtherLink *parent;
256    bool number;
257    UNSERIALIZE_OBJPTR(parent);
258    UNSERIALIZE_SCALAR(number);
259
260    link = parent->link[number];
261
262    packet = new EthPacketData(16384);
263    packet->unserialize("packet", cp, section);
264}
265
266
267Serializable *
268LinkDelayEvent::createForUnserialize(Checkpoint *cp, const string &section)
269{
270    return new LinkDelayEvent();
271}
272
273REGISTER_SERIALIZEABLE("LinkDelayEvent", LinkDelayEvent)
274
275BEGIN_DECLARE_SIM_OBJECT_PARAMS(EtherLink)
276
277    SimObjectParam<EtherInt *> int1;
278    SimObjectParam<EtherInt *> int2;
279    Param<double> speed;
280    Param<Tick> delay;
281    Param<Tick> delay_var;
282    SimObjectParam<EtherDump *> dump;
283
284END_DECLARE_SIM_OBJECT_PARAMS(EtherLink)
285
286BEGIN_INIT_SIM_OBJECT_PARAMS(EtherLink)
287
288    INIT_PARAM(int1, "interface 1"),
289    INIT_PARAM(int2, "interface 2"),
290    INIT_PARAM(speed, "link speed in bits per second"),
291    INIT_PARAM(delay, "transmit delay of packets in us"),
292    INIT_PARAM(delay_var, "Difference in amount of time to traverse wire"),
293    INIT_PARAM(dump, "object to dump network packets to")
294
295END_INIT_SIM_OBJECT_PARAMS(EtherLink)
296
297CREATE_SIM_OBJECT(EtherLink)
298{
299    return new EtherLink(getInstanceName(), int1, int2, speed, delay, delay_var,
300                         dump);
301}
302
303REGISTER_SIM_OBJECT("EtherLink", EtherLink)
304