gem5/src/dev/net/etherswitch.cc
Brandon Potter a928a438b8 style: [patch 3/22] reduce include dependencies in some headers
Used cppclean to help identify useless includes and removed them. This
involved erroneously included headers, but also cases where forward
declarations could have been used rather than a full include.
2016-11-09 14:27:40 -06:00

357 lines
11 KiB
C++

/*
* Copyright (c) 2014 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Anthony Gutierrez
* Mohammad Alian
*/
/* @file
* Device model for an ethernet switch
*/
#include "dev/net/etherswitch.hh"
#include "base/random.hh"
#include "base/trace.hh"
#include "debug/EthernetAll.hh"
#include "sim/core.hh"
using namespace std;
EtherSwitch::EtherSwitch(const Params *p)
: EtherObject(p), ttl(p->time_to_live)
{
for (int i = 0; i < p->port_interface_connection_count; ++i) {
std::string interfaceName = csprintf("%s.interface%d", name(), i);
Interface *interface = new Interface(interfaceName, this,
p->output_buffer_size, p->delay,
p->delay_var, p->fabric_speed, i);
interfaces.push_back(interface);
}
}
EtherSwitch::~EtherSwitch()
{
for (auto it : interfaces)
delete it;
interfaces.clear();
}
EtherInt*
EtherSwitch::getEthPort(const std::string &if_name, int idx)
{
if (idx < 0 || idx >= interfaces.size())
return nullptr;
Interface *interface = interfaces.at(idx);
panic_if(interface->getPeer(), "interface already connected\n");
return interface;
}
bool
EtherSwitch::Interface::PortFifo::push(EthPacketPtr ptr, unsigned senderId)
{
assert(ptr->length);
_size += ptr->length;
fifo.emplace_hint(fifo.end(), ptr, curTick(), senderId);
// Drop the extra pushed packets from end of the fifo
while (avail() < 0) {
DPRINTF(Ethernet, "Fifo is full. Drop packet: len=%d\n",
std::prev(fifo.end())->packet->length);
_size -= std::prev(fifo.end())->packet->length;
fifo.erase(std::prev(fifo.end()));
}
if (empty()) {
warn("EtherSwitch: Packet length (%d) exceeds the maximum storage "
"capacity of port fifo (%d)", ptr->length, _maxsize);
}
// Return true if the newly pushed packet gets inserted
// at the head of the queue, otherwise return false
// We need this information to deschedule the event that has been
// scheduled for the old head of queue packet and schedule a new one
if (!empty() && fifo.begin()->packet == ptr) {
return true;
}
return false;
}
void
EtherSwitch::Interface::PortFifo::pop()
{
if (empty())
return;
assert(_size >= fifo.begin()->packet->length);
// Erase the packet at the head of the queue
_size -= fifo.begin()->packet->length;
fifo.erase(fifo.begin());
}
void
EtherSwitch::Interface::PortFifo::clear()
{
fifo.clear();
_size = 0;
}
EtherSwitch::Interface::Interface(const std::string &name,
EtherSwitch *etherSwitch,
uint64_t outputBufferSize, Tick delay,
Tick delay_var, double rate, unsigned id)
: EtherInt(name), ticksPerByte(rate), switchDelay(delay),
delayVar(delay_var), interfaceId(id), parent(etherSwitch),
outputFifo(name + ".outputFifo", outputBufferSize), txEvent(this)
{
}
bool
EtherSwitch::Interface::recvPacket(EthPacketPtr packet)
{
Net::EthAddr destMacAddr(packet->data);
Net::EthAddr srcMacAddr(&packet->data[6]);
learnSenderAddr(srcMacAddr, this);
Interface *receiver = lookupDestPort(destMacAddr);
if (!receiver || destMacAddr.multicast() || destMacAddr.broadcast()) {
for (auto it : parent->interfaces)
if (it != this)
it->enqueue(packet, interfaceId);
} else {
DPRINTF(Ethernet, "sending packet from MAC %x on port "
"%s to MAC %x on port %s\n", uint64_t(srcMacAddr),
this->name(), uint64_t(destMacAddr), receiver->name());
receiver->enqueue(packet, interfaceId);
}
// At the output port, we either have buffer space (no drop) or
// don't (drop packet); in both cases packet is received on
// the interface successfully and there is no notion of busy
// interface here (as we don't have inputFifo)
return true;
}
void
EtherSwitch::Interface::enqueue(EthPacketPtr packet, unsigned senderId)
{
// assuming per-interface transmission events,
// if the newly push packet gets inserted at the head of the queue
// (either there was nothing in the queue or the priority of the new
// packet was higher than the packets already in the fifo)
// then we need to schedule an event at
// "curTick" + "switchingDelay of the packet at the head of the fifo"
// to send this packet out the external link
// otherwise, there is already a txEvent scheduled
if (outputFifo.push(packet, senderId)) {
parent->reschedule(txEvent, curTick() + switchingDelay(), true);
}
}
void
EtherSwitch::Interface::transmit()
{
// there should be something in the output queue
assert(!outputFifo.empty());
if (!sendPacket(outputFifo.front())) {
DPRINTF(Ethernet, "output port busy...retry later\n");
if (!txEvent.scheduled())
parent->schedule(txEvent, curTick() + retryTime);
} else {
DPRINTF(Ethernet, "packet sent: len=%d\n", outputFifo.front()->length);
outputFifo.pop();
// schedule an event to send the pkt at
// the head of queue, if there is any
if (!outputFifo.empty()) {
parent->schedule(txEvent, curTick() + switchingDelay());
}
}
}
Tick
EtherSwitch::Interface::switchingDelay()
{
Tick delay = (Tick)ceil(((double)outputFifo.front()->simLength
* ticksPerByte) + 1.0);
if (delayVar != 0)
delay += random_mt.random<Tick>(0, delayVar);
delay += switchDelay;
return delay;
}
EtherSwitch::Interface*
EtherSwitch::Interface::lookupDestPort(Net::EthAddr destMacAddr)
{
auto it = parent->forwardingTable.find(uint64_t(destMacAddr));
if (it == parent->forwardingTable.end()) {
DPRINTF(Ethernet, "no entry in forwaring table for MAC: "
"%x\n", uint64_t(destMacAddr));
return nullptr;
}
// check if this entry is valid based on TTL and lastUseTime
if ((curTick() - it->second.lastUseTime) > parent->ttl) {
// TTL for this mapping has been expired, so this item is not
// valide anymore, let's remove it from the map
parent->forwardingTable.erase(it);
return nullptr;
}
DPRINTF(Ethernet, "found entry for MAC address %x on port %s\n",
uint64_t(destMacAddr), it->second.interface->name());
return it->second.interface;
}
void
EtherSwitch::Interface::learnSenderAddr(Net::EthAddr srcMacAddr,
Interface *sender)
{
// learn the port for the sending MAC address
auto it = parent->forwardingTable.find(uint64_t(srcMacAddr));
// if the port for sender's MAC address is not cached,
// cache it now, otherwise just update lastUseTime time
if (it == parent->forwardingTable.end()) {
DPRINTF(Ethernet, "adding forwarding table entry for MAC "
" address %x on port %s\n", uint64_t(srcMacAddr),
sender->name());
EtherSwitch::SwitchTableEntry forwardingTableEntry;
forwardingTableEntry.interface = sender;
forwardingTableEntry.lastUseTime = curTick();
parent->forwardingTable.insert(std::make_pair(uint64_t(srcMacAddr),
forwardingTableEntry));
} else {
it->second.lastUseTime = curTick();
}
}
void
EtherSwitch::serialize(CheckpointOut &cp) const
{
for (auto it : interfaces)
it->serializeSection(cp, it->name());
}
void
EtherSwitch::unserialize(CheckpointIn &cp)
{
for (auto it : interfaces)
it->unserializeSection(cp, it->name());
}
void
EtherSwitch::Interface::serialize(CheckpointOut &cp) const
{
bool event_scheduled = txEvent.scheduled();
SERIALIZE_SCALAR(event_scheduled);
if (event_scheduled) {
Tick event_time = txEvent.when();
SERIALIZE_SCALAR(event_time);
}
outputFifo.serializeSection(cp, "outputFifo");
}
void
EtherSwitch::Interface::unserialize(CheckpointIn &cp)
{
bool event_scheduled;
UNSERIALIZE_SCALAR(event_scheduled);
if (event_scheduled) {
Tick event_time;
UNSERIALIZE_SCALAR(event_time);
parent->schedule(txEvent, event_time);
}
outputFifo.unserializeSection(cp, "outputFifo");
}
void
EtherSwitch::Interface::PortFifoEntry::serialize(CheckpointOut &cp) const
{
packet->serialize("packet", cp);
SERIALIZE_SCALAR(recvTick);
SERIALIZE_SCALAR(srcId);
}
void
EtherSwitch::Interface::PortFifoEntry::unserialize(CheckpointIn &cp)
{
packet = make_shared<EthPacketData>(16384);
packet->unserialize("packet", cp);
UNSERIALIZE_SCALAR(recvTick);
UNSERIALIZE_SCALAR(srcId);
}
void
EtherSwitch::Interface::PortFifo::serialize(CheckpointOut &cp) const
{
SERIALIZE_SCALAR(_size);
int fifosize = fifo.size();
SERIALIZE_SCALAR(fifosize);
int i = 0;
for (const auto &entry : fifo)
entry.serializeSection(cp, csprintf("entry%d", i++));
}
void
EtherSwitch::Interface::PortFifo::unserialize(CheckpointIn &cp)
{
UNSERIALIZE_SCALAR(_size);
int fifosize;
UNSERIALIZE_SCALAR(fifosize);
fifo.clear();
for (int i = 0; i < fifosize; ++i) {
PortFifoEntry entry(nullptr, 0, 0);
entry.unserializeSection(cp, csprintf("entry%d", i));
fifo.insert(entry);
}
}
EtherSwitch *
EtherSwitchParams::create()
{
return new EtherSwitch(this);
}