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 "debug/Ethernet.hh"
  44 #include "debug/EthernetData.hh"
  45 #include "dev/etherdump.hh"
  46 #include "dev/etherint.hh"
  47 #include "dev/etherlink.hh"
  48 #include "dev/etherpkt.hh"
  49 #include "params/EtherLink.hh"
  50 #include "sim/core.hh"
  51 #include "sim/serialize.hh"
  52 #include "sim/system.hh"
  53
  54 using namespace std;
  55
  56 EtherLink::EtherLink(const Params *p)
  57     : EtherObject(p)
  58 {
  59     link[0] = new Link(name() + ".link0", this, 0, p->speed,
  60                        p->delay, p->delay_var, p->dump);
  61     link[1] = new Link(name() + ".link1", this, 1, p->speed,
  62                        p->delay, p->delay_var, p->dump);
  63
  64     interface[0] = new Interface(name() + ".int0", link[0], link[1]);
  65     interface[1] = new Interface(name() + ".int1", link[1], link[0]);
  66 }
  67
  68
  69 EtherLink::~EtherLink()
  70 {
  71     delete link[0];
  72     delete link[1];
  73
  74     delete interface[0];
  75     delete interface[1];
  76 }
  77
  78 EtherInt*
  79 EtherLink::getEthPort(const std::string &if_name, int idx)
  80 {
  81     Interface *i;
  82     if (if_name == "int0")
  83         i = interface[0];
  84     else if (if_name == "int1")
  85         i = interface[1];
  86     else
  87         return NULL;
  88     if (i->getPeer())
  89         panic("interface already connected to\n");
  90
  91     return i;
  92 }
  93
  94
  95 EtherLink::Interface::Interface(const string &name, Link *tx, Link *rx)
  96     : EtherInt(name), txlink(tx)
  97 {
  98     tx->setTxInt(this);
  99     rx->setRxInt(this);
 100 }
 101
 102 EtherLink::Link::Link(const string &name, EtherLink *p, int num,
 103                       double rate, Tick delay, Tick delay_var, EtherDump *d)
 104     : objName(name), parent(p), number(num), txint(NULL), rxint(NULL),
 105       ticksPerByte(rate), linkDelay(delay), delayVar(delay_var), dump(d),
 106       doneEvent(this)
 107 { }
 108
 109 void
 110 EtherLink::serialize(ostream &os)
 111 {
 112     link[0]->serialize("link0", os);
 113     link[1]->serialize("link1", os);
 114 }
 115
 116 void
 117 EtherLink::unserialize(Checkpoint *cp, const string &section)
 118 {
 119     link[0]->unserialize("link0", cp, section);
 120     link[1]->unserialize("link1", cp, section);
 121 }
 122
 123 void
 124 EtherLink::Link::txComplete(EthPacketPtr packet)
 125 {
 126     DPRINTF(Ethernet, "packet received: len=%d\n", packet->length);
 127     DDUMP(EthernetData, packet->data, packet->length);
 128     rxint->sendPacket(packet);
 129 }
 130
 131 class LinkDelayEvent : public Event
 132 {
 133   protected:
 134     EtherLink::Link *link;
 135     EthPacketPtr packet;
 136
 137   public:
 138     // non-scheduling version for createForUnserialize()
 139     LinkDelayEvent();
 140     LinkDelayEvent(EtherLink::Link *link, EthPacketPtr pkt);
 141
 142     void process();
 143
 144     virtual void serialize(ostream &os);
 145     void unserialize(Checkpoint *cp, const string &section) {}
 146     void unserialize(Checkpoint *cp, const string &section,
 147                      EventQueue *eventq);
 148     static Serializable *createForUnserialize(Checkpoint *cp,
 149                                               const string &section);
 150 };
 151
 152 void
 153 EtherLink::Link::txDone()
 154 {
 155     if (dump)
 156         dump->dump(packet);
 157
 158     if (linkDelay > 0) {
 159         DPRINTF(Ethernet, "packet delayed: delay=%d\n", linkDelay);
 160         Event *event = new LinkDelayEvent(this, packet);
 161         parent->schedule(event, curTick() + linkDelay);
 162     } else {
 163         txComplete(packet);
 164     }
 165
 166     packet = 0;
 167     assert(!busy());
 168
 169     txint->sendDone();
 170 }
 171
 172 bool
 173 EtherLink::Link::transmit(EthPacketPtr pkt)
 174 {
 175     if (busy()) {
 176         DPRINTF(Ethernet, "packet not sent, link busy\n");
 177         return false;
 178     }
 179
 180     DPRINTF(Ethernet, "packet sent: len=%d\n", pkt->length);
 181     DDUMP(EthernetData, pkt->data, pkt->length);
 182
 183     packet = pkt;
 184     Tick delay = (Tick)ceil(((double)pkt->length * ticksPerByte) + 1.0);
 185     if (delayVar != 0)
 186         delay += random_mt.random<Tick>(0, delayVar);
 187
 188     DPRINTF(Ethernet, "scheduling packet: delay=%d, (rate=%f)\n",
 189             delay, ticksPerByte);
 190     parent->schedule(doneEvent, curTick() + delay);
 191
 192     return true;
 193 }
 194
 195 void
 196 EtherLink::Link::serialize(const string &base, ostream &os)
 197 {
 198     bool packet_exists = packet != nullptr;
 199     paramOut(os, base + ".packet_exists", packet_exists);
 200     if (packet_exists)
 201         packet->serialize(base + ".packet", os);
 202
 203     bool event_scheduled = doneEvent.scheduled();
 204     paramOut(os, base + ".event_scheduled", event_scheduled);
 205     if (event_scheduled) {
 206         Tick event_time = doneEvent.when();
 207         paramOut(os, base + ".event_time", event_time);
 208     }
 209
 210 }
 211
 212 void
 213 EtherLink::Link::unserialize(const string &base, Checkpoint *cp,
 214                              const string &section)
 215 {
 216     bool packet_exists;
 217     paramIn(cp, section, base + ".packet_exists", packet_exists);
 218     if (packet_exists) {
 219         packet = make_shared<EthPacketData>(16384);
 220         packet->unserialize(base + ".packet", cp, section);
 221     }
 222
 223     bool event_scheduled;
 224     paramIn(cp, section, base + ".event_scheduled", event_scheduled);
 225     if (event_scheduled) {
 226         Tick event_time;
 227         paramIn(cp, section, base + ".event_time", event_time);
 228         parent->schedule(doneEvent, event_time);
 229     }
 230 }
 231
 232 LinkDelayEvent::LinkDelayEvent()
 233     : Event(Default_Pri, AutoSerialize | AutoDelete), link(NULL)
 234 {
 235 }
 236
 237 LinkDelayEvent::LinkDelayEvent(EtherLink::Link *l, EthPacketPtr p)
 238     : Event(Default_Pri, AutoSerialize | AutoDelete), link(l), packet(p)
 239 {
 240 }
 241
 242 void
 243 LinkDelayEvent::process()
 244 {
 245     link->txComplete(packet);
 246 }
 247
 248 void
 249 LinkDelayEvent::serialize(ostream &os)
 250 {
 251     paramOut(os, "type", string("LinkDelayEvent"));
 252     Event::serialize(os);
 253
 254     EtherLink *parent = link->parent;
 255     bool number = link->number;
 256     SERIALIZE_OBJPTR(parent);
 257     SERIALIZE_SCALAR(number);
 258
 259     packet->serialize("packet", os);
 260 }
 261
 262
 263 void
 264 LinkDelayEvent::unserialize(Checkpoint *cp, const string &section,
 265                             EventQueue *eventq)
 266 {
 267     Event::unserialize(cp, section, eventq);
 268
 269     EtherLink *parent;
 270     bool number;
 271     UNSERIALIZE_OBJPTR(parent);
 272     UNSERIALIZE_SCALAR(number);
 273
 274     link = parent->link[number];
 275
 276     packet = make_shared<EthPacketData>(16384);
 277     packet->unserialize("packet", cp, section);
 278 }
 279
 280
 281 Serializable *
 282 LinkDelayEvent::createForUnserialize(Checkpoint *cp, const string &section)
 283 {
 284     return new LinkDelayEvent();
 285 }
 286
 287 REGISTER_SERIALIZEABLE("LinkDelayEvent", LinkDelayEvent)
 288
 289 EtherLink *
 290 EtherLinkParams::create()
 291 {
 292     return new EtherLink(this);
 293 }