PerfectSwitch.cc revision 8608:02d7ac5fb855
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 "debug/RubyNetwork.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 to_string(m_switch_id), to_string(port), to_string(j)); 75 m_in[port][j]->setDescription(desc); 76 m_in[port][j]->setIncomingLink(port); 77 m_in[port][j]->setVnet(j); 78 } 79} 80 81void 82PerfectSwitch::addOutPort(const vector<MessageBuffer*>& out, 83 const NetDest& routing_table_entry) 84{ 85 assert(out.size() == m_virtual_networks); 86 87 // Setup link order 88 LinkOrder l; 89 l.m_value = 0; 90 l.m_link = m_out.size(); 91 m_link_order.push_back(l); 92 93 // Add to routing table 94 m_out.push_back(out); 95 m_routing_table.push_back(routing_table_entry); 96} 97 98void 99PerfectSwitch::clearRoutingTables() 100{ 101 m_routing_table.clear(); 102} 103 104void 105PerfectSwitch::clearBuffers() 106{ 107 for (int i = 0; i < m_in.size(); i++){ 108 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 109 m_in[i][vnet]->clear(); 110 } 111 } 112 113 for (int i = 0; i < m_out.size(); i++){ 114 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 115 m_out[i][vnet]->clear(); 116 } 117 } 118} 119 120void 121PerfectSwitch::reconfigureOutPort(const NetDest& routing_table_entry) 122{ 123 m_routing_table.push_back(routing_table_entry); 124} 125 126PerfectSwitch::~PerfectSwitch() 127{ 128} 129 130void 131PerfectSwitch::wakeup() 132{ 133 MsgPtr msg_ptr; 134 135 // Give the highest numbered link priority most of the time 136 m_wakeups_wo_switch++; 137 int highest_prio_vnet = m_virtual_networks-1; 138 int lowest_prio_vnet = 0; 139 int decrementer = 1; 140 NetworkMessage* net_msg_ptr = NULL; 141 142 // invert priorities to avoid starvation seen in the component network 143 if (m_wakeups_wo_switch > PRIORITY_SWITCH_LIMIT) { 144 m_wakeups_wo_switch = 0; 145 highest_prio_vnet = 0; 146 lowest_prio_vnet = m_virtual_networks-1; 147 decrementer = -1; 148 } 149 150 // For all components incoming queues 151 for (int vnet = highest_prio_vnet; 152 (vnet * decrementer) >= (decrementer * lowest_prio_vnet); 153 vnet -= decrementer) { 154 155 // This is for round-robin scheduling 156 int incoming = m_round_robin_start; 157 m_round_robin_start++; 158 if (m_round_robin_start >= m_in.size()) { 159 m_round_robin_start = 0; 160 } 161 162 if(m_pending_message_count[vnet] > 0) { 163 // for all input ports, use round robin scheduling 164 for (int counter = 0; counter < m_in.size(); counter++) { 165 // Round robin scheduling 166 incoming++; 167 if (incoming >= m_in.size()) { 168 incoming = 0; 169 } 170 171 // temporary vectors to store the routing results 172 vector<LinkID> output_links; 173 vector<NetDest> output_link_destinations; 174 175 // Is there a message waiting? 176 while (m_in[incoming][vnet]->isReady()) { 177 DPRINTF(RubyNetwork, "incoming: %d\n", incoming); 178 179 // Peek at message 180 msg_ptr = m_in[incoming][vnet]->peekMsgPtr(); 181 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 182 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 183 184 output_links.clear(); 185 output_link_destinations.clear(); 186 NetDest msg_dsts = 187 net_msg_ptr->getInternalDestination(); 188 189 // Unfortunately, the token-protocol sends some 190 // zero-destination messages, so this assert isn't valid 191 // assert(msg_dsts.count() > 0); 192 193 assert(m_link_order.size() == m_routing_table.size()); 194 assert(m_link_order.size() == m_out.size()); 195 196 if (m_network_ptr->getAdaptiveRouting()) { 197 if (m_network_ptr->isVNetOrdered(vnet)) { 198 // Don't adaptively route 199 for (int out = 0; out < m_out.size(); out++) { 200 m_link_order[out].m_link = out; 201 m_link_order[out].m_value = 0; 202 } 203 } else { 204 // Find how clogged each link is 205 for (int out = 0; out < m_out.size(); out++) { 206 int out_queue_length = 0; 207 for (int v = 0; v < m_virtual_networks; v++) { 208 out_queue_length += m_out[out][v]->getSize(); 209 } 210 int value = 211 (out_queue_length << 8) | (random() & 0xff); 212 m_link_order[out].m_link = out; 213 m_link_order[out].m_value = value; 214 } 215 216 // Look at the most empty link first 217 sort(m_link_order.begin(), m_link_order.end()); 218 } 219 } 220 221 for (int i = 0; i < m_routing_table.size(); i++) { 222 // pick the next link to look at 223 int link = m_link_order[i].m_link; 224 NetDest dst = m_routing_table[link]; 225 DPRINTF(RubyNetwork, "dst: %s\n", dst); 226 227 if (!msg_dsts.intersectionIsNotEmpty(dst)) 228 continue; 229 230 // Remember what link we're using 231 output_links.push_back(link); 232 233 // Need to remember which destinations need this 234 // message in another vector. This Set is the 235 // intersection of the routing_table entry and the 236 // current destination set. The intersection must 237 // not be empty, since we are inside "if" 238 output_link_destinations.push_back(msg_dsts.AND(dst)); 239 240 // Next, we update the msg_destination not to 241 // include those nodes that were already handled 242 // by this link 243 msg_dsts.removeNetDest(dst); 244 } 245 246 assert(msg_dsts.count() == 0); 247 //assert(output_links.size() > 0); 248 249 // Check for resources - for all outgoing queues 250 bool enough = true; 251 for (int i = 0; i < output_links.size(); i++) { 252 int outgoing = output_links[i]; 253 if (!m_out[outgoing][vnet]->areNSlotsAvailable(1)) 254 enough = false; 255 DPRINTF(RubyNetwork, "Checking if node is blocked ..." 256 "outgoing: %d, vnet: %d, enough: %d\n", 257 outgoing, vnet, enough); 258 } 259 260 // There were not enough resources 261 if (!enough) { 262 g_eventQueue_ptr->scheduleEvent(this, 1); 263 DPRINTF(RubyNetwork, "Can't deliver message since a node " 264 "is blocked\n"); 265 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 266 break; // go to next incoming port 267 } 268 269 MsgPtr unmodified_msg_ptr; 270 271 if (output_links.size() > 1) { 272 // If we are sending this message down more than 273 // one link (size>1), we need to make a copy of 274 // the message so each branch can have a different 275 // internal destination we need to create an 276 // unmodified MsgPtr because the MessageBuffer 277 // enqueue func will modify the message 278 279 // This magic line creates a private copy of the 280 // message 281 unmodified_msg_ptr = msg_ptr->clone(); 282 } 283 284 // Enqueue it - for all outgoing queues 285 for (int i=0; i<output_links.size(); i++) { 286 int outgoing = output_links[i]; 287 288 if (i > 0) { 289 // create a private copy of the unmodified 290 // message 291 msg_ptr = unmodified_msg_ptr->clone(); 292 } 293 294 // Change the internal destination set of the 295 // message so it knows which destinations this 296 // link is responsible for. 297 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 298 net_msg_ptr->getInternalDestination() = 299 output_link_destinations[i]; 300 301 // Enqeue msg 302 DPRINTF(RubyNetwork, "Enqueuing net msg from " 303 "inport[%d][%d] to outport [%d][%d].\n", 304 incoming, vnet, outgoing, vnet); 305 306 m_out[outgoing][vnet]->enqueue(msg_ptr); 307 } 308 309 // Dequeue msg 310 m_in[incoming][vnet]->pop(); 311 m_pending_message_count[vnet]--; 312 } 313 } 314 } 315 } 316} 317 318void 319PerfectSwitch::storeEventInfo(int info) 320{ 321 m_pending_message_count[info]++; 322} 323 324void 325PerfectSwitch::printStats(std::ostream& out) const 326{ 327 out << "PerfectSwitch printStats" << endl; 328} 329 330void 331PerfectSwitch::clearStats() 332{ 333} 334 335void 336PerfectSwitch::printConfig(std::ostream& out) const 337{ 338} 339 340void 341PerfectSwitch::print(std::ostream& out) const 342{ 343 out << "[PerfectSwitch " << m_switch_id << "]"; 344} 345 346