PerfectSwitch.cc revision 7780:42da07116e12
1/* 2 * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood 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 29#include <algorithm> 30 31#include "mem/protocol/Protocol.hh" 32#include "mem/ruby/buffers/MessageBuffer.hh" 33#include "mem/ruby/network/simple/PerfectSwitch.hh" 34#include "mem/ruby/network/simple/SimpleNetwork.hh" 35#include "mem/ruby/profiler/Profiler.hh" 36#include "mem/ruby/slicc_interface/NetworkMessage.hh" 37#include "mem/ruby/system/System.hh" 38 39using namespace std; 40 41const int PRIORITY_SWITCH_LIMIT = 128; 42 43// Operator for helper class 44bool 45operator<(const LinkOrder& l1, const LinkOrder& l2) 46{ 47 return (l1.m_value < l2.m_value); 48} 49 50PerfectSwitch::PerfectSwitch(SwitchID sid, SimpleNetwork* network_ptr) 51{ 52 m_virtual_networks = network_ptr->getNumberOfVirtualNetworks(); 53 m_switch_id = sid; 54 m_round_robin_start = 0; 55 m_network_ptr = network_ptr; 56 m_wakeups_wo_switch = 0; 57} 58 59void 60PerfectSwitch::addInPort(const vector<MessageBuffer*>& in) 61{ 62 assert(in.size() == m_virtual_networks); 63 NodeID port = m_in.size(); 64 m_in.push_back(in); 65 for (int j = 0; j < m_virtual_networks; j++) { 66 m_in[port][j]->setConsumer(this); 67 string desc = csprintf("[Queue from port %s %s %s to PerfectSwitch]", 68 NodeIDToString(m_switch_id), NodeIDToString(port), 69 NodeIDToString(j)); 70 m_in[port][j]->setDescription(desc); 71 } 72} 73 74void 75PerfectSwitch::addOutPort(const vector<MessageBuffer*>& out, 76 const NetDest& routing_table_entry) 77{ 78 assert(out.size() == m_virtual_networks); 79 80 // Setup link order 81 LinkOrder l; 82 l.m_value = 0; 83 l.m_link = m_out.size(); 84 m_link_order.push_back(l); 85 86 // Add to routing table 87 m_out.push_back(out); 88 m_routing_table.push_back(routing_table_entry); 89} 90 91void 92PerfectSwitch::clearRoutingTables() 93{ 94 m_routing_table.clear(); 95} 96 97void 98PerfectSwitch::clearBuffers() 99{ 100 for (int i = 0; i < m_in.size(); i++){ 101 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 102 m_in[i][vnet]->clear(); 103 } 104 } 105 106 for (int i = 0; i < m_out.size(); i++){ 107 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 108 m_out[i][vnet]->clear(); 109 } 110 } 111} 112 113void 114PerfectSwitch::reconfigureOutPort(const NetDest& routing_table_entry) 115{ 116 m_routing_table.push_back(routing_table_entry); 117} 118 119PerfectSwitch::~PerfectSwitch() 120{ 121} 122 123void 124PerfectSwitch::wakeup() 125{ 126 DPRINTF(RubyNetwork, "m_switch_id: %d\n",m_switch_id); 127 128 MsgPtr msg_ptr; 129 130 // Give the highest numbered link priority most of the time 131 m_wakeups_wo_switch++; 132 int highest_prio_vnet = m_virtual_networks-1; 133 int lowest_prio_vnet = 0; 134 int decrementer = 1; 135 NetworkMessage* net_msg_ptr = NULL; 136 137 // invert priorities to avoid starvation seen in the component network 138 if (m_wakeups_wo_switch > PRIORITY_SWITCH_LIMIT) { 139 m_wakeups_wo_switch = 0; 140 highest_prio_vnet = 0; 141 lowest_prio_vnet = m_virtual_networks-1; 142 decrementer = -1; 143 } 144 145 // For all components incoming queues 146 for (int vnet = highest_prio_vnet; 147 (vnet * decrementer) >= (decrementer * lowest_prio_vnet); 148 vnet -= decrementer) { 149 150 // This is for round-robin scheduling 151 int incoming = m_round_robin_start; 152 m_round_robin_start++; 153 if (m_round_robin_start >= m_in.size()) { 154 m_round_robin_start = 0; 155 } 156 157 // for all input ports, use round robin scheduling 158 for (int counter = 0; counter < m_in.size(); counter++) { 159 // Round robin scheduling 160 incoming++; 161 if (incoming >= m_in.size()) { 162 incoming = 0; 163 } 164 165 // temporary vectors to store the routing results 166 vector<LinkID> output_links; 167 vector<NetDest> output_link_destinations; 168 169 // Is there a message waiting? 170 while (m_in[incoming][vnet]->isReady()) { 171 DPRINTF(RubyNetwork, "incoming: %d\n", incoming); 172 173 // Peek at message 174 msg_ptr = m_in[incoming][vnet]->peekMsgPtr(); 175 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 176 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 177 178 output_links.clear(); 179 output_link_destinations.clear(); 180 NetDest msg_dsts = 181 net_msg_ptr->getInternalDestination(); 182 183 // Unfortunately, the token-protocol sends some 184 // zero-destination messages, so this assert isn't valid 185 // assert(msg_dsts.count() > 0); 186 187 assert(m_link_order.size() == m_routing_table.size()); 188 assert(m_link_order.size() == m_out.size()); 189 190 if (m_network_ptr->getAdaptiveRouting()) { 191 if (m_network_ptr->isVNetOrdered(vnet)) { 192 // Don't adaptively route 193 for (int out = 0; out < m_out.size(); out++) { 194 m_link_order[out].m_link = out; 195 m_link_order[out].m_value = 0; 196 } 197 } else { 198 // Find how clogged each link is 199 for (int out = 0; out < m_out.size(); out++) { 200 int out_queue_length = 0; 201 for (int v = 0; v < m_virtual_networks; v++) { 202 out_queue_length += m_out[out][v]->getSize(); 203 } 204 int value = 205 (out_queue_length << 8) | (random() & 0xff); 206 m_link_order[out].m_link = out; 207 m_link_order[out].m_value = value; 208 } 209 210 // Look at the most empty link first 211 sort(m_link_order.begin(), m_link_order.end()); 212 } 213 } 214 215 for (int i = 0; i < m_routing_table.size(); i++) { 216 // pick the next link to look at 217 int link = m_link_order[i].m_link; 218 NetDest dst = m_routing_table[link]; 219 DPRINTF(RubyNetwork, "dst: %s\n", dst); 220 221 if (!msg_dsts.intersectionIsNotEmpty(dst)) 222 continue; 223 224 // Remember what link we're using 225 output_links.push_back(link); 226 227 // Need to remember which destinations need this 228 // message in another vector. This Set is the 229 // intersection of the routing_table entry and the 230 // current destination set. The intersection must 231 // not be empty, since we are inside "if" 232 output_link_destinations.push_back(msg_dsts.AND(dst)); 233 234 // Next, we update the msg_destination not to 235 // include those nodes that were already handled 236 // by this link 237 msg_dsts.removeNetDest(dst); 238 } 239 240 assert(msg_dsts.count() == 0); 241 //assert(output_links.size() > 0); 242 243 // Check for resources - for all outgoing queues 244 bool enough = true; 245 for (int i = 0; i < output_links.size(); i++) { 246 int outgoing = output_links[i]; 247 if (!m_out[outgoing][vnet]->areNSlotsAvailable(1)) 248 enough = false; 249 DPRINTF(RubyNetwork, "Checking if node is blocked\n" 250 "outgoing: %d, vnet: %d, enough: %d\n", 251 outgoing, vnet, enough); 252 } 253 254 // There were not enough resources 255 if (!enough) { 256 g_eventQueue_ptr->scheduleEvent(this, 1); 257 DPRINTF(RubyNetwork, "Can't deliver message since a node " 258 "is blocked\n" 259 "Message: %s\n", (*net_msg_ptr)); 260 break; // go to next incoming port 261 } 262 263 MsgPtr unmodified_msg_ptr; 264 265 if (output_links.size() > 1) { 266 // If we are sending this message down more than 267 // one link (size>1), we need to make a copy of 268 // the message so each branch can have a different 269 // internal destination we need to create an 270 // unmodified MsgPtr because the MessageBuffer 271 // enqueue func will modify the message 272 273 // This magic line creates a private copy of the 274 // message 275 unmodified_msg_ptr = msg_ptr->clone(); 276 } 277 278 // Enqueue it - for all outgoing queues 279 for (int i=0; i<output_links.size(); i++) { 280 int outgoing = output_links[i]; 281 282 if (i > 0) { 283 // create a private copy of the unmodified 284 // message 285 msg_ptr = unmodified_msg_ptr->clone(); 286 } 287 288 // Change the internal destination set of the 289 // message so it knows which destinations this 290 // link is responsible for. 291 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 292 net_msg_ptr->getInternalDestination() = 293 output_link_destinations[i]; 294 295 // Enqeue msg 296 DPRINTF(RubyNetwork, "Switch: %d enqueuing net msg from " 297 "inport[%d][%d] to outport [%d][%d] time: %lld.\n", 298 m_switch_id, incoming, vnet, outgoing, vnet, 299 g_eventQueue_ptr->getTime()); 300 301 m_out[outgoing][vnet]->enqueue(msg_ptr); 302 } 303 304 // Dequeue msg 305 m_in[incoming][vnet]->pop(); 306 } 307 } 308 } 309} 310 311void 312PerfectSwitch::printStats(std::ostream& out) const 313{ 314 out << "PerfectSwitch printStats" << endl; 315} 316 317void 318PerfectSwitch::clearStats() 319{ 320} 321 322void 323PerfectSwitch::printConfig(std::ostream& out) const 324{ 325} 326 327void 328PerfectSwitch::print(std::ostream& out) const 329{ 330 out << "[PerfectSwitch " << m_switch_id << "]"; 331} 332 333