PerfectSwitch.cc revision 9508:dde110931867
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 "base/cast.hh" 32#include "debug/RubyNetwork.hh" 33#include "mem/ruby/buffers/MessageBuffer.hh" 34#include "mem/ruby/network/simple/PerfectSwitch.hh" 35#include "mem/ruby/network/simple/SimpleNetwork.hh" 36#include "mem/ruby/network/simple/Switch.hh" 37#include "mem/ruby/slicc_interface/NetworkMessage.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, Switch *sw, uint32_t virt_nets) 51 : Consumer(sw) 52{ 53 m_switch_id = sid; 54 m_round_robin_start = 0; 55 m_wakeups_wo_switch = 0; 56 m_virtual_networks = virt_nets; 57} 58 59void 60PerfectSwitch::init(SimpleNetwork *network_ptr) 61{ 62 m_network_ptr = network_ptr; 63 64 for(int i = 0;i < m_virtual_networks;++i) 65 { 66 m_pending_message_count.push_back(0); 67 } 68} 69 70void 71PerfectSwitch::addInPort(const vector<MessageBuffer*>& in) 72{ 73 assert(in.size() == m_virtual_networks); 74 NodeID port = m_in.size(); 75 m_in.push_back(in); 76 77 for (int j = 0; j < m_virtual_networks; j++) { 78 m_in[port][j]->setConsumer(this); 79 80 string desc = csprintf("[Queue from port %s %s %s to PerfectSwitch]", 81 to_string(m_switch_id), to_string(port), to_string(j)); 82 m_in[port][j]->setDescription(desc); 83 m_in[port][j]->setIncomingLink(port); 84 m_in[port][j]->setVnet(j); 85 } 86} 87 88void 89PerfectSwitch::addOutPort(const vector<MessageBuffer*>& out, 90 const NetDest& routing_table_entry) 91{ 92 assert(out.size() == m_virtual_networks); 93 94 // Setup link order 95 LinkOrder l; 96 l.m_value = 0; 97 l.m_link = m_out.size(); 98 m_link_order.push_back(l); 99 100 // Add to routing table 101 m_out.push_back(out); 102 m_routing_table.push_back(routing_table_entry); 103} 104 105void 106PerfectSwitch::clearRoutingTables() 107{ 108 m_routing_table.clear(); 109} 110 111void 112PerfectSwitch::clearBuffers() 113{ 114 for (int i = 0; i < m_in.size(); i++){ 115 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 116 m_in[i][vnet]->clear(); 117 } 118 } 119 120 for (int i = 0; i < m_out.size(); i++){ 121 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 122 m_out[i][vnet]->clear(); 123 } 124 } 125} 126 127void 128PerfectSwitch::reconfigureOutPort(const NetDest& routing_table_entry) 129{ 130 m_routing_table.push_back(routing_table_entry); 131} 132 133PerfectSwitch::~PerfectSwitch() 134{ 135} 136 137void 138PerfectSwitch::wakeup() 139{ 140 MsgPtr msg_ptr; 141 142 // Give the highest numbered link priority most of the time 143 m_wakeups_wo_switch++; 144 int highest_prio_vnet = m_virtual_networks-1; 145 int lowest_prio_vnet = 0; 146 int decrementer = 1; 147 NetworkMessage* net_msg_ptr = NULL; 148 149 // invert priorities to avoid starvation seen in the component network 150 if (m_wakeups_wo_switch > PRIORITY_SWITCH_LIMIT) { 151 m_wakeups_wo_switch = 0; 152 highest_prio_vnet = 0; 153 lowest_prio_vnet = m_virtual_networks-1; 154 decrementer = -1; 155 } 156 157 // For all components incoming queues 158 for (int vnet = highest_prio_vnet; 159 (vnet * decrementer) >= (decrementer * lowest_prio_vnet); 160 vnet -= decrementer) { 161 162 // This is for round-robin scheduling 163 int incoming = m_round_robin_start; 164 m_round_robin_start++; 165 if (m_round_robin_start >= m_in.size()) { 166 m_round_robin_start = 0; 167 } 168 169 if(m_pending_message_count[vnet] > 0) { 170 // for all input ports, use round robin scheduling 171 for (int counter = 0; counter < m_in.size(); counter++) { 172 // Round robin scheduling 173 incoming++; 174 if (incoming >= m_in.size()) { 175 incoming = 0; 176 } 177 178 // temporary vectors to store the routing results 179 vector<LinkID> output_links; 180 vector<NetDest> output_link_destinations; 181 182 // Is there a message waiting? 183 while (m_in[incoming][vnet]->isReady()) { 184 DPRINTF(RubyNetwork, "incoming: %d\n", incoming); 185 186 // Peek at message 187 msg_ptr = m_in[incoming][vnet]->peekMsgPtr(); 188 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 189 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 190 191 output_links.clear(); 192 output_link_destinations.clear(); 193 NetDest msg_dsts = 194 net_msg_ptr->getInternalDestination(); 195 196 // Unfortunately, the token-protocol sends some 197 // zero-destination messages, so this assert isn't valid 198 // assert(msg_dsts.count() > 0); 199 200 assert(m_link_order.size() == m_routing_table.size()); 201 assert(m_link_order.size() == m_out.size()); 202 203 if (m_network_ptr->getAdaptiveRouting()) { 204 if (m_network_ptr->isVNetOrdered(vnet)) { 205 // Don't adaptively route 206 for (int out = 0; out < m_out.size(); out++) { 207 m_link_order[out].m_link = out; 208 m_link_order[out].m_value = 0; 209 } 210 } else { 211 // Find how clogged each link is 212 for (int out = 0; out < m_out.size(); out++) { 213 int out_queue_length = 0; 214 for (int v = 0; v < m_virtual_networks; v++) { 215 out_queue_length += m_out[out][v]->getSize(); 216 } 217 int value = 218 (out_queue_length << 8) | (random() & 0xff); 219 m_link_order[out].m_link = out; 220 m_link_order[out].m_value = value; 221 } 222 223 // Look at the most empty link first 224 sort(m_link_order.begin(), m_link_order.end()); 225 } 226 } 227 228 for (int i = 0; i < m_routing_table.size(); i++) { 229 // pick the next link to look at 230 int link = m_link_order[i].m_link; 231 NetDest dst = m_routing_table[link]; 232 DPRINTF(RubyNetwork, "dst: %s\n", dst); 233 234 if (!msg_dsts.intersectionIsNotEmpty(dst)) 235 continue; 236 237 // Remember what link we're using 238 output_links.push_back(link); 239 240 // Need to remember which destinations need this 241 // message in another vector. This Set is the 242 // intersection of the routing_table entry and the 243 // current destination set. The intersection must 244 // not be empty, since we are inside "if" 245 output_link_destinations.push_back(msg_dsts.AND(dst)); 246 247 // Next, we update the msg_destination not to 248 // include those nodes that were already handled 249 // by this link 250 msg_dsts.removeNetDest(dst); 251 } 252 253 assert(msg_dsts.count() == 0); 254 //assert(output_links.size() > 0); 255 256 // Check for resources - for all outgoing queues 257 bool enough = true; 258 for (int i = 0; i < output_links.size(); i++) { 259 int outgoing = output_links[i]; 260 if (!m_out[outgoing][vnet]->areNSlotsAvailable(1)) 261 enough = false; 262 DPRINTF(RubyNetwork, "Checking if node is blocked ..." 263 "outgoing: %d, vnet: %d, enough: %d\n", 264 outgoing, vnet, enough); 265 } 266 267 // There were not enough resources 268 if (!enough) { 269 scheduleEvent(Cycles(1)); 270 DPRINTF(RubyNetwork, "Can't deliver message since a node " 271 "is blocked\n"); 272 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 273 break; // go to next incoming port 274 } 275 276 MsgPtr unmodified_msg_ptr; 277 278 if (output_links.size() > 1) { 279 // If we are sending this message down more than 280 // one link (size>1), we need to make a copy of 281 // the message so each branch can have a different 282 // internal destination we need to create an 283 // unmodified MsgPtr because the MessageBuffer 284 // enqueue func will modify the message 285 286 // This magic line creates a private copy of the 287 // message 288 unmodified_msg_ptr = msg_ptr->clone(); 289 } 290 291 // Enqueue it - for all outgoing queues 292 for (int i=0; i<output_links.size(); i++) { 293 int outgoing = output_links[i]; 294 295 if (i > 0) { 296 // create a private copy of the unmodified 297 // message 298 msg_ptr = unmodified_msg_ptr->clone(); 299 } 300 301 // Change the internal destination set of the 302 // message so it knows which destinations this 303 // link is responsible for. 304 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 305 net_msg_ptr->getInternalDestination() = 306 output_link_destinations[i]; 307 308 // Enqeue msg 309 DPRINTF(RubyNetwork, "Enqueuing net msg from " 310 "inport[%d][%d] to outport [%d][%d].\n", 311 incoming, vnet, outgoing, vnet); 312 313 m_out[outgoing][vnet]->enqueue(msg_ptr); 314 } 315 316 // Dequeue msg 317 m_in[incoming][vnet]->pop(); 318 m_pending_message_count[vnet]--; 319 } 320 } 321 } 322 } 323} 324 325void 326PerfectSwitch::storeEventInfo(int info) 327{ 328 m_pending_message_count[info]++; 329} 330 331void 332PerfectSwitch::printStats(std::ostream& out) const 333{ 334 out << "PerfectSwitch printStats" << endl; 335} 336 337void 338PerfectSwitch::clearStats() 339{ 340} 341 342void 343PerfectSwitch::print(std::ostream& out) const 344{ 345 out << "[PerfectSwitch " << m_switch_id << "]"; 346} 347