src/dev/etherlink.cc

   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 "params/EtherLink.hh"
  48 #include "sim/serialize.hh"
  49 #include "sim/system.hh"
  50 #include "sim/core.hh"
  51
  52 using namespace std;
  53
  54 EtherLink::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
  70 EtherLink::~EtherLink()
  71 {
  72     delete link[0];
  73     delete link[1];
  74
  75     delete interface[0];
  76     delete interface[1];
  77 }
  78
  79 EtherLink::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
  86 EtherLink::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
  93 void
  94 EtherLink::serialize(ostream &os)
  95 {
  96     link[0]->serialize("link0", os);
  97     link[1]->serialize("link1", os);
  98 }
  99
 100 void
 101 EtherLink::unserialize(Checkpoint *cp, const string &section)
 102 {
 103     link[0]->unserialize("link0", cp, section);
 104     link[1]->unserialize("link1", cp, section);
 105 }
 106
 107 void
 108 EtherLink::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
 115 class 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
 134 void
 135 EtherLink::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
 153 bool
 154 EtherLink::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
 177 void
 178 EtherLink::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
 194 void
 195 EtherLink::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
 214 LinkDelayEvent::LinkDelayEvent()
 215     : Event(&mainEventQueue), link(NULL)
 216 {
 217     setFlags(AutoSerialize);
 218     setFlags(AutoDelete);
 219 }
 220
 221 LinkDelayEvent::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
 229 void
 230 LinkDelayEvent::process()
 231 {
 232     link->txComplete(packet);
 233 }
 234
 235 void
 236 LinkDelayEvent::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
 250 void
 251 LinkDelayEvent::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
 267 Serializable *
 268 LinkDelayEvent::createForUnserialize(Checkpoint *cp, const string &section)
 269 {
 270     return new LinkDelayEvent();
 271 }
 272
 273 REGISTER_SERIALIZEABLE("LinkDelayEvent", LinkDelayEvent)
 274
 275 EtherLink *
 276 EtherLinkParams::create()
 277 {
 278     return new EtherLink(name, int1, int2, speed, delay, delay_var, dump);
 279 }