PerfectSwitch.cc revision 7973:e5550966464a
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 for(int i = 0;i < m_virtual_networks;++i) 59 { 60 m_pending_message_count.push_back(0); 61 } 62} 63 64void 65PerfectSwitch::addInPort(const vector<MessageBuffer*>& in) 66{ 67 assert(in.size() == m_virtual_networks); 68 NodeID port = m_in.size(); 69 m_in.push_back(in); 70 71 for (int j = 0; j < m_virtual_networks; j++) { 72 m_in[port][j]->setConsumer(this); 73 string desc = csprintf("[Queue from port %s %s %s to PerfectSwitch]", 74 NodeIDToString(m_switch_id), NodeIDToString(port), 75 NodeIDToString(j)); 76 m_in[port][j]->setDescription(desc); 77 m_in[port][j]->setIncomingLink(port); 78 m_in[port][j]->setVnet(j); 79 } 80} 81 82void 83PerfectSwitch::addOutPort(const vector<MessageBuffer*>& out, 84 const NetDest& routing_table_entry) 85{ 86 assert(out.size() == m_virtual_networks); 87 88 // Setup link order 89 LinkOrder l; 90 l.m_value = 0; 91 l.m_link = m_out.size(); 92 m_link_order.push_back(l); 93 94 // Add to routing table 95 m_out.push_back(out); 96 m_routing_table.push_back(routing_table_entry); 97} 98 99void 100PerfectSwitch::clearRoutingTables() 101{ 102 m_routing_table.clear(); 103} 104 105void 106PerfectSwitch::clearBuffers() 107{ 108 for (int i = 0; i < m_in.size(); i++){ 109 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 110 m_in[i][vnet]->clear(); 111 } 112 } 113 114 for (int i = 0; i < m_out.size(); i++){ 115 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 116 m_out[i][vnet]->clear(); 117 } 118 } 119} 120 121void 122PerfectSwitch::reconfigureOutPort(const NetDest& routing_table_entry) 123{ 124 m_routing_table.push_back(routing_table_entry); 125} 126 127PerfectSwitch::~PerfectSwitch() 128{ 129} 130 131void 132PerfectSwitch::wakeup() 133{ 134 DPRINTF(RubyNetwork, "m_switch_id: %d\n",m_switch_id); 135 136 MsgPtr msg_ptr; 137 138 // Give the highest numbered link priority most of the time 139 m_wakeups_wo_switch++; 140 int highest_prio_vnet = m_virtual_networks-1; 141 int lowest_prio_vnet = 0; 142 int decrementer = 1; 143 NetworkMessage* net_msg_ptr = NULL; 144 145 // invert priorities to avoid starvation seen in the component network 146 if (m_wakeups_wo_switch > PRIORITY_SWITCH_LIMIT) { 147 m_wakeups_wo_switch = 0; 148 highest_prio_vnet = 0; 149 lowest_prio_vnet = m_virtual_networks-1; 150 decrementer = -1; 151 } 152 153 // For all components incoming queues 154 for (int vnet = highest_prio_vnet; 155 (vnet * decrementer) >= (decrementer * lowest_prio_vnet); 156 vnet -= decrementer) { 157 158 // This is for round-robin scheduling 159 int incoming = m_round_robin_start; 160 m_round_robin_start++; 161 if (m_round_robin_start >= m_in.size()) { 162 m_round_robin_start = 0; 163 } 164 165 if(m_pending_message_count[vnet] > 0) { 166 // for all input ports, use round robin scheduling 167 for (int counter = 0; counter < m_in.size(); counter++) { 168 // Round robin scheduling 169 incoming++; 170 if (incoming >= m_in.size()) { 171 incoming = 0; 172 } 173 174 // temporary vectors to store the routing results 175 vector<LinkID> output_links; 176 vector<NetDest> output_link_destinations; 177 178 // Is there a message waiting? 179 while (m_in[incoming][vnet]->isReady()) { 180 DPRINTF(RubyNetwork, "incoming: %d\n", incoming); 181 182 // Peek at message 183 msg_ptr = m_in[incoming][vnet]->peekMsgPtr(); 184 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 185 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 186 187 output_links.clear(); 188 output_link_destinations.clear(); 189 NetDest msg_dsts = 190 net_msg_ptr->getInternalDestination(); 191 192 // Unfortunately, the token-protocol sends some 193 // zero-destination messages, so this assert isn't valid 194 // assert(msg_dsts.count() > 0); 195 196 assert(m_link_order.size() == m_routing_table.size()); 197 assert(m_link_order.size() == m_out.size()); 198 199 if (m_network_ptr->getAdaptiveRouting()) { 200 if (m_network_ptr->isVNetOrdered(vnet)) { 201 // Don't adaptively route 202 for (int out = 0; out < m_out.size(); out++) { 203 m_link_order[out].m_link = out; 204 m_link_order[out].m_value = 0; 205 } 206 } else { 207 // Find how clogged each link is 208 for (int out = 0; out < m_out.size(); out++) { 209 int out_queue_length = 0; 210 for (int v = 0; v < m_virtual_networks; v++) { 211 out_queue_length += m_out[out][v]->getSize(); 212 } 213 int value = 214 (out_queue_length << 8) | (random() & 0xff); 215 m_link_order[out].m_link = out; 216 m_link_order[out].m_value = value; 217 } 218 219 // Look at the most empty link first 220 sort(m_link_order.begin(), m_link_order.end()); 221 } 222 } 223 224 for (int i = 0; i < m_routing_table.size(); i++) { 225 // pick the next link to look at 226 int link = m_link_order[i].m_link; 227 NetDest dst = m_routing_table[link]; 228 DPRINTF(RubyNetwork, "dst: %s\n", dst); 229 230 if (!msg_dsts.intersectionIsNotEmpty(dst)) 231 continue; 232 233 // Remember what link we're using 234 output_links.push_back(link); 235 236 // Need to remember which destinations need this 237 // message in another vector. This Set is the 238 // intersection of the routing_table entry and the 239 // current destination set. The intersection must 240 // not be empty, since we are inside "if" 241 output_link_destinations.push_back(msg_dsts.AND(dst)); 242 243 // Next, we update the msg_destination not to 244 // include those nodes that were already handled 245 // by this link 246 msg_dsts.removeNetDest(dst); 247 } 248 249 assert(msg_dsts.count() == 0); 250 //assert(output_links.size() > 0); 251 252 // Check for resources - for all outgoing queues 253 bool enough = true; 254 for (int i = 0; i < output_links.size(); i++) { 255 int outgoing = output_links[i]; 256 if (!m_out[outgoing][vnet]->areNSlotsAvailable(1)) 257 enough = false; 258 DPRINTF(RubyNetwork, "Checking if node is blocked\n" 259 "outgoing: %d, vnet: %d, enough: %d\n", 260 outgoing, vnet, enough); 261 } 262 263 // There were not enough resources 264 if (!enough) { 265 g_eventQueue_ptr->scheduleEvent(this, 1); 266 DPRINTF(RubyNetwork, "Can't deliver message since a node " 267 "is blocked\n" 268 "Message: %s\n", (*net_msg_ptr)); 269 break; // go to next incoming port 270 } 271 272 MsgPtr unmodified_msg_ptr; 273 274 if (output_links.size() > 1) { 275 // If we are sending this message down more than 276 // one link (size>1), we need to make a copy of 277 // the message so each branch can have a different 278 // internal destination we need to create an 279 // unmodified MsgPtr because the MessageBuffer 280 // enqueue func will modify the message 281 282 // This magic line creates a private copy of the 283 // message 284 unmodified_msg_ptr = msg_ptr->clone(); 285 } 286 287 // Enqueue it - for all outgoing queues 288 for (int i=0; i<output_links.size(); i++) { 289 int outgoing = output_links[i]; 290 291 if (i > 0) { 292 // create a private copy of the unmodified 293 // message 294 msg_ptr = unmodified_msg_ptr->clone(); 295 } 296 297 // Change the internal destination set of the 298 // message so it knows which destinations this 299 // link is responsible for. 300 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 301 net_msg_ptr->getInternalDestination() = 302 output_link_destinations[i]; 303 304 // Enqeue msg 305 DPRINTF(RubyNetwork, "Switch: %d enqueuing net msg from " 306 "inport[%d][%d] to outport [%d][%d] time: %lld.\n", 307 m_switch_id, incoming, vnet, outgoing, vnet, 308 g_eventQueue_ptr->getTime()); 309 310 m_out[outgoing][vnet]->enqueue(msg_ptr); 311 } 312 313 // Dequeue msg 314 m_in[incoming][vnet]->pop(); 315 m_pending_message_count[vnet]--; 316 } 317 } 318 } 319 } 320} 321 322void 323PerfectSwitch::storeEventInfo(int info) 324{ 325 m_pending_message_count[info]++; 326} 327 328void 329PerfectSwitch::printStats(std::ostream& out) const 330{ 331 out << "PerfectSwitch printStats" << endl; 332} 333 334void 335PerfectSwitch::clearStats() 336{ 337} 338 339void 340PerfectSwitch::printConfig(std::ostream& out) const 341{ 342} 343 344void 345PerfectSwitch::print(std::ostream& out) const 346{ 347 out << "[PerfectSwitch " << m_switch_id << "]"; 348} 349 350