gem5/src/mem/ruby/network/garnet/flexible-pipeline/NetworkInterface.cc
2015-10-14 00:29:38 -05:00

385 lines
12 KiB
C++

/*
* Copyright (c) 2008 Princeton University
* 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: Niket Agarwal
*/
#include <cassert>
#include <cmath>
#include "base/cast.hh"
#include "base/stl_helpers.hh"
#include "debug/RubyNetwork.hh"
#include "mem/ruby/network/MessageBuffer.hh"
#include "mem/ruby/network/garnet/flexible-pipeline/NetworkInterface.hh"
#include "mem/ruby/network/garnet/flexible-pipeline/flitBuffer.hh"
#include "mem/ruby/slicc_interface/Message.hh"
using namespace std;
using m5::stl_helpers::deletePointers;
NetworkInterface::NetworkInterface(const Params *p)
: ClockedObject(p), FlexibleConsumer(this)
{
m_id = p->id;
m_virtual_networks = p->virt_nets;
m_vc_per_vnet = p->vcs_per_vnet;
m_num_vcs = m_vc_per_vnet*m_virtual_networks;
m_vc_round_robin = 0;
// instantiating the NI flit buffers
m_ni_buffers.resize(m_num_vcs);
for (int i =0; i < m_num_vcs; i++)
m_ni_buffers[i] = new flitBuffer();
m_vc_allocator.resize(m_virtual_networks);
for (int i = 0; i < m_virtual_networks; i++) {
m_vc_allocator[i] = 0;
}
for (int i = 0; i < m_num_vcs; i++) {
m_out_vc_state.push_back(new OutVcState(i));
}
}
NetworkInterface::~NetworkInterface()
{
deletePointers(m_out_vc_state);
deletePointers(m_ni_buffers);
delete outSrcQueue;
}
void
NetworkInterface::addInPort(NetworkLink *in_link)
{
inNetLink = in_link;
in_link->setLinkConsumer(this);
}
void
NetworkInterface::addOutPort(NetworkLink *out_link)
{
outNetLink = out_link;
outSrcQueue = new flitBuffer();
out_link->setSourceQueue(outSrcQueue);
out_link->setSource(this);
}
void
NetworkInterface::addNode(vector<MessageBuffer*>& in,
vector<MessageBuffer*>& out)
{
inNode_ptr = in;
outNode_ptr = out;
for (auto& it: in) {
if (it != nullptr) {
it->setConsumer(this);
}
}
}
void
NetworkInterface::request_vc(int in_vc, int in_port, NetDest destination,
Cycles request_time)
{
inNetLink->grant_vc_link(in_vc, request_time);
}
bool
NetworkInterface::flitisizeMessage(MsgPtr msg_ptr, int vnet)
{
Message *net_msg_ptr = msg_ptr.get();
NetDest net_msg_dest = net_msg_ptr->getDestination();
// get all the destinations associated with this message.
vector<NodeID> dest_nodes = net_msg_dest.getAllDest();
// Number of flits is dependent on the link bandwidth available.
// This is expressed in terms of bytes/cycle or the flit size
int num_flits = (int) ceil((double) m_net_ptr->MessageSizeType_to_int(
net_msg_ptr->getMessageSize())/m_net_ptr->getNiFlitSize());
// loop to convert all multicast messages into unicast messages
for (int ctr = 0; ctr < dest_nodes.size(); ctr++) {
int vc = calculateVC(vnet); // this will return a free output vc
if (vc == -1) {
// did not find a free output vc
return false ;
}
MsgPtr new_msg_ptr = msg_ptr->clone();
NodeID destID = dest_nodes[ctr];
Message *new_net_msg_ptr = new_msg_ptr.get();
if (dest_nodes.size() > 1) {
NetDest personal_dest;
for (int m = 0; m < (int) MachineType_NUM; m++) {
if ((destID >= MachineType_base_number((MachineType) m)) &&
destID < MachineType_base_number((MachineType) (m+1))) {
// calculating the NetDest associated with this destID
personal_dest.clear();
personal_dest.add((MachineID) {(MachineType) m, (destID -
MachineType_base_number((MachineType) m))});
new_net_msg_ptr->getDestination() = personal_dest;
break;
}
}
net_msg_dest.removeNetDest(personal_dest);
// removing the destination from the original message to reflect
// that a message with this particular destination has been
// flitisized and an output vc is acquired
net_msg_ptr->getDestination().removeNetDest(personal_dest);
}
for (int i = 0; i < num_flits; i++) {
m_net_ptr->increment_injected_flits(vnet);
flit *fl = new flit(i, vc, vnet, num_flits, new_msg_ptr,
curCycle());
fl->set_delay(curCycle() - ticksToCycles(msg_ptr->getTime()));
m_ni_buffers[vc]->insert(fl);
}
m_out_vc_state[vc]->setState(VC_AB_, curCycle());
// setting an output vc request for the next hop.
// This flit will be ready to traverse the link and into the next hop
// only when an output vc is acquired at the next hop
outNetLink->request_vc_link(
vc, new_net_msg_ptr->getDestination(), curCycle());
}
return true ;
}
// An output vc has been granted at the next hop to one of the vc's.
// We have to update the state of the vc to reflect this
void
NetworkInterface::grant_vc(int out_port, int vc, Cycles grant_time)
{
assert(m_out_vc_state[vc]->isInState(VC_AB_, grant_time));
m_out_vc_state[vc]->grant_vc(grant_time);
scheduleEvent(Cycles(1));
}
// The tail flit corresponding to this vc has been buffered at the next hop
// and thus this vc is now free
void
NetworkInterface::release_vc(int out_port, int vc, Cycles release_time)
{
assert(m_out_vc_state[vc]->isInState(ACTIVE_, release_time));
m_out_vc_state[vc]->setState(IDLE_, release_time);
scheduleEvent(Cycles(1));
}
// Looking for a free output vc
int
NetworkInterface::calculateVC(int vnet)
{
int vc_per_vnet;
if (m_net_ptr->isVNetOrdered(vnet))
vc_per_vnet = 1;
else
vc_per_vnet = m_vc_per_vnet;
for (int i = 0; i < vc_per_vnet; i++) {
int delta = m_vc_allocator[vnet];
m_vc_allocator[vnet]++;
if (m_vc_allocator[vnet] == vc_per_vnet)
m_vc_allocator[vnet] = 0;
if (m_out_vc_state[(vnet*m_vc_per_vnet) + delta]->
isInState(IDLE_, curCycle())) {
return ((vnet*m_vc_per_vnet) + delta);
}
}
return -1;
}
/*
* The NI wakeup checks whether there are any ready messages in the protocol
* buffer. If yes, it picks that up, flitisizes it into a number of flits and
* puts it into an output buffer and schedules the output link.
* On a wakeup it also checks whether there are flits in the input link.
* If yes, it picks them up and if the flit is a tail, the NI inserts the
* corresponding message into the protocol buffer.
*/
void
NetworkInterface::wakeup()
{
MsgPtr msg_ptr;
//Checking for messages coming from the protocol
// can pick up a message/cycle for each virtual net
for (int vnet = 0; vnet < inNode_ptr.size(); ++vnet) {
MessageBuffer *b = inNode_ptr[vnet];
if (b == nullptr) {
continue;
}
while (b->isReady(clockEdge())) { // Is there a message waiting
msg_ptr = b->peekMsgPtr();
if (flitisizeMessage(msg_ptr, vnet)) {
b->dequeue(clockEdge());
} else {
break;
}
}
}
scheduleOutputLink();
checkReschedule();
/*********** Picking messages destined for this NI **********/
if (inNetLink->isReady()) {
flit *t_flit = inNetLink->consumeLink();
if (t_flit->get_type() == TAIL_ || t_flit->get_type() == HEAD_TAIL_) {
DPRINTF(RubyNetwork, "m_id: %d, Message delivered at time: %lld\n",
m_id, curCycle());
outNode_ptr[t_flit->get_vnet()]->enqueue(
t_flit->get_msg_ptr(), clockEdge(), cyclesToTicks(Cycles(1)));
// signal the upstream router that this vc can be freed now
inNetLink->release_vc_link(t_flit->get_vc(),
curCycle() + Cycles(1));
}
int vnet = t_flit->get_vnet();
m_net_ptr->increment_received_flits(vnet);
Cycles network_delay = curCycle() - t_flit->get_creation_time();
Cycles queueing_delay = t_flit->get_delay();
m_net_ptr->increment_network_latency(network_delay, vnet);
m_net_ptr->increment_queueing_latency(queueing_delay, vnet);
delete t_flit;
}
}
/* This function looks at the NI buffers and if some buffer has flits which
* are ready to traverse the link in the next cycle and also the downstream
* output vc associated with this flit has buffers left, the link is scheduled
* for the next cycle
*/
void
NetworkInterface::scheduleOutputLink()
{
int vc = m_vc_round_robin;
m_vc_round_robin++;
if (m_vc_round_robin == m_num_vcs)
m_vc_round_robin = 0;
for (int i = 0; i < m_num_vcs; i++) {
vc++;
if (vc == m_num_vcs)
vc = 0;
if (m_ni_buffers[vc]->isReady(curCycle())) {
if (m_out_vc_state[vc]->isInState(ACTIVE_, curCycle()) &&
outNetLink->isBufferNotFull_link(vc)) { // buffer backpressure
// Just removing the flit
flit *t_flit = m_ni_buffers[vc]->getTopFlit();
t_flit->set_time(curCycle() + Cycles(1));
outSrcQueue->insert(t_flit);
// schedule the out link
outNetLink->
scheduleEventAbsolute(clockEdge(Cycles(1)));
return;
}
}
}
}
void
NetworkInterface::checkReschedule()
{
for (const auto& it : inNode_ptr) {
if (it == nullptr) {
continue;
}
while (it->isReady(clockEdge())) { // Is there a message waiting
scheduleEvent(Cycles(1));
return;
}
}
for (int vc = 0; vc < m_num_vcs; vc++) {
if (m_ni_buffers[vc]->isReady(curCycle() + Cycles(1))) {
scheduleEvent(Cycles(1));
return;
}
}
}
bool
NetworkInterface::functionalRead(Packet *pkt)
{
// Go through the internal buffers
for (unsigned int i = 0; i < m_ni_buffers.size(); ++i) {
if (m_ni_buffers[i]->functionalRead(pkt)) {
return true;
}
}
// Go through the buffer between this network interface and the router
if (outSrcQueue->functionalRead(pkt)) {
return true;
}
return false;
}
uint32_t
NetworkInterface::functionalWrite(Packet *pkt)
{
uint32_t num_functional_writes = 0;
for (unsigned int i = 0; i < m_ni_buffers.size(); ++i) {
num_functional_writes += m_ni_buffers[i]->functionalWrite(pkt);
}
num_functional_writes += outSrcQueue->functionalWrite(pkt);
return num_functional_writes;
}
void
NetworkInterface::print(std::ostream& out) const
{
out << "[Network Interface]";
}
NetworkInterface *
GarnetNetworkInterfaceParams::create()
{
return new NetworkInterface(this);
}