PerfectSwitch.cc revision 9499:b03b556a8fbb
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, Switch *sw) 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 m_in[port][j]->setClockObj(sw); 80 81 string desc = csprintf("[Queue from port %s %s %s to PerfectSwitch]", 82 to_string(m_switch_id), to_string(port), to_string(j)); 83 m_in[port][j]->setDescription(desc); 84 m_in[port][j]->setIncomingLink(port); 85 m_in[port][j]->setVnet(j); 86 } 87} 88 89void 90PerfectSwitch::addOutPort(const vector<MessageBuffer*>& out, 91 const NetDest& routing_table_entry) 92{ 93 assert(out.size() == m_virtual_networks); 94 95 // Setup link order 96 LinkOrder l; 97 l.m_value = 0; 98 l.m_link = m_out.size(); 99 m_link_order.push_back(l); 100 101 // Add to routing table 102 m_out.push_back(out); 103 m_routing_table.push_back(routing_table_entry); 104} 105 106void 107PerfectSwitch::clearRoutingTables() 108{ 109 m_routing_table.clear(); 110} 111 112void 113PerfectSwitch::clearBuffers() 114{ 115 for (int i = 0; i < m_in.size(); i++){ 116 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 117 m_in[i][vnet]->clear(); 118 } 119 } 120 121 for (int i = 0; i < m_out.size(); i++){ 122 for(int vnet = 0; vnet < m_virtual_networks; vnet++) { 123 m_out[i][vnet]->clear(); 124 } 125 } 126} 127 128void 129PerfectSwitch::reconfigureOutPort(const NetDest& routing_table_entry) 130{ 131 m_routing_table.push_back(routing_table_entry); 132} 133 134PerfectSwitch::~PerfectSwitch() 135{ 136} 137 138void 139PerfectSwitch::wakeup() 140{ 141 MsgPtr msg_ptr; 142 143 // Give the highest numbered link priority most of the time 144 m_wakeups_wo_switch++; 145 int highest_prio_vnet = m_virtual_networks-1; 146 int lowest_prio_vnet = 0; 147 int decrementer = 1; 148 NetworkMessage* net_msg_ptr = NULL; 149 150 // invert priorities to avoid starvation seen in the component network 151 if (m_wakeups_wo_switch > PRIORITY_SWITCH_LIMIT) { 152 m_wakeups_wo_switch = 0; 153 highest_prio_vnet = 0; 154 lowest_prio_vnet = m_virtual_networks-1; 155 decrementer = -1; 156 } 157 158 // For all components incoming queues 159 for (int vnet = highest_prio_vnet; 160 (vnet * decrementer) >= (decrementer * lowest_prio_vnet); 161 vnet -= decrementer) { 162 163 // This is for round-robin scheduling 164 int incoming = m_round_robin_start; 165 m_round_robin_start++; 166 if (m_round_robin_start >= m_in.size()) { 167 m_round_robin_start = 0; 168 } 169 170 if(m_pending_message_count[vnet] > 0) { 171 // for all input ports, use round robin scheduling 172 for (int counter = 0; counter < m_in.size(); counter++) { 173 // Round robin scheduling 174 incoming++; 175 if (incoming >= m_in.size()) { 176 incoming = 0; 177 } 178 179 // temporary vectors to store the routing results 180 vector<LinkID> output_links; 181 vector<NetDest> output_link_destinations; 182 183 // Is there a message waiting? 184 while (m_in[incoming][vnet]->isReady()) { 185 DPRINTF(RubyNetwork, "incoming: %d\n", incoming); 186 187 // Peek at message 188 msg_ptr = m_in[incoming][vnet]->peekMsgPtr(); 189 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 190 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 191 192 output_links.clear(); 193 output_link_destinations.clear(); 194 NetDest msg_dsts = 195 net_msg_ptr->getInternalDestination(); 196 197 // Unfortunately, the token-protocol sends some 198 // zero-destination messages, so this assert isn't valid 199 // assert(msg_dsts.count() > 0); 200 201 assert(m_link_order.size() == m_routing_table.size()); 202 assert(m_link_order.size() == m_out.size()); 203 204 if (m_network_ptr->getAdaptiveRouting()) { 205 if (m_network_ptr->isVNetOrdered(vnet)) { 206 // Don't adaptively route 207 for (int out = 0; out < m_out.size(); out++) { 208 m_link_order[out].m_link = out; 209 m_link_order[out].m_value = 0; 210 } 211 } else { 212 // Find how clogged each link is 213 for (int out = 0; out < m_out.size(); out++) { 214 int out_queue_length = 0; 215 for (int v = 0; v < m_virtual_networks; v++) { 216 out_queue_length += m_out[out][v]->getSize(); 217 } 218 int value = 219 (out_queue_length << 8) | (random() & 0xff); 220 m_link_order[out].m_link = out; 221 m_link_order[out].m_value = value; 222 } 223 224 // Look at the most empty link first 225 sort(m_link_order.begin(), m_link_order.end()); 226 } 227 } 228 229 for (int i = 0; i < m_routing_table.size(); i++) { 230 // pick the next link to look at 231 int link = m_link_order[i].m_link; 232 NetDest dst = m_routing_table[link]; 233 DPRINTF(RubyNetwork, "dst: %s\n", dst); 234 235 if (!msg_dsts.intersectionIsNotEmpty(dst)) 236 continue; 237 238 // Remember what link we're using 239 output_links.push_back(link); 240 241 // Need to remember which destinations need this 242 // message in another vector. This Set is the 243 // intersection of the routing_table entry and the 244 // current destination set. The intersection must 245 // not be empty, since we are inside "if" 246 output_link_destinations.push_back(msg_dsts.AND(dst)); 247 248 // Next, we update the msg_destination not to 249 // include those nodes that were already handled 250 // by this link 251 msg_dsts.removeNetDest(dst); 252 } 253 254 assert(msg_dsts.count() == 0); 255 //assert(output_links.size() > 0); 256 257 // Check for resources - for all outgoing queues 258 bool enough = true; 259 for (int i = 0; i < output_links.size(); i++) { 260 int outgoing = output_links[i]; 261 if (!m_out[outgoing][vnet]->areNSlotsAvailable(1)) 262 enough = false; 263 DPRINTF(RubyNetwork, "Checking if node is blocked ..." 264 "outgoing: %d, vnet: %d, enough: %d\n", 265 outgoing, vnet, enough); 266 } 267 268 // There were not enough resources 269 if (!enough) { 270 scheduleEvent(Cycles(1)); 271 DPRINTF(RubyNetwork, "Can't deliver message since a node " 272 "is blocked\n"); 273 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 274 break; // go to next incoming port 275 } 276 277 MsgPtr unmodified_msg_ptr; 278 279 if (output_links.size() > 1) { 280 // If we are sending this message down more than 281 // one link (size>1), we need to make a copy of 282 // the message so each branch can have a different 283 // internal destination we need to create an 284 // unmodified MsgPtr because the MessageBuffer 285 // enqueue func will modify the message 286 287 // This magic line creates a private copy of the 288 // message 289 unmodified_msg_ptr = msg_ptr->clone(); 290 } 291 292 // Enqueue it - for all outgoing queues 293 for (int i=0; i<output_links.size(); i++) { 294 int outgoing = output_links[i]; 295 296 if (i > 0) { 297 // create a private copy of the unmodified 298 // message 299 msg_ptr = unmodified_msg_ptr->clone(); 300 } 301 302 // Change the internal destination set of the 303 // message so it knows which destinations this 304 // link is responsible for. 305 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 306 net_msg_ptr->getInternalDestination() = 307 output_link_destinations[i]; 308 309 // Enqeue msg 310 DPRINTF(RubyNetwork, "Enqueuing net msg from " 311 "inport[%d][%d] to outport [%d][%d].\n", 312 incoming, vnet, outgoing, vnet); 313 314 m_out[outgoing][vnet]->enqueue(msg_ptr); 315 } 316 317 // Dequeue msg 318 m_in[incoming][vnet]->pop(); 319 m_pending_message_count[vnet]--; 320 } 321 } 322 } 323 } 324} 325 326void 327PerfectSwitch::storeEventInfo(int info) 328{ 329 m_pending_message_count[info]++; 330} 331 332void 333PerfectSwitch::printStats(std::ostream& out) const 334{ 335 out << "PerfectSwitch printStats" << endl; 336} 337 338void 339PerfectSwitch::clearStats() 340{ 341} 342 343void 344PerfectSwitch::print(std::ostream& out) const 345{ 346 out << "[PerfectSwitch " << m_switch_id << "]"; 347} 348