PerfectSwitch.cc revision 9117:49116b947194
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/profiler/Profiler.hh" 37#include "mem/ruby/slicc_interface/NetworkMessage.hh" 38#include "mem/ruby/system/System.hh" 39 40using namespace std; 41 42const int PRIORITY_SWITCH_LIMIT = 128; 43 44// Operator for helper class 45bool 46operator<(const LinkOrder& l1, const LinkOrder& l2) 47{ 48 return (l1.m_value < l2.m_value); 49} 50 51PerfectSwitch::PerfectSwitch(SwitchID sid, SimpleNetwork* network_ptr) 52{ 53 m_virtual_networks = network_ptr->getNumberOfVirtualNetworks(); 54 m_switch_id = sid; 55 m_round_robin_start = 0; 56 m_network_ptr = network_ptr; 57 m_wakeups_wo_switch = 0; 58 59 for(int i = 0;i < m_virtual_networks;++i) 60 { 61 m_pending_message_count.push_back(0); 62 } 63} 64 65void 66PerfectSwitch::addInPort(const vector<MessageBuffer*>& in) 67{ 68 assert(in.size() == m_virtual_networks); 69 NodeID port = m_in.size(); 70 m_in.push_back(in); 71 72 for (int j = 0; j < m_virtual_networks; j++) { 73 m_in[port][j]->setConsumer(this); 74 string desc = csprintf("[Queue from port %s %s %s to PerfectSwitch]", 75 to_string(m_switch_id), to_string(port), to_string(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 MsgPtr msg_ptr; 135 136 // Give the highest numbered link priority most of the time 137 m_wakeups_wo_switch++; 138 int highest_prio_vnet = m_virtual_networks-1; 139 int lowest_prio_vnet = 0; 140 int decrementer = 1; 141 NetworkMessage* net_msg_ptr = NULL; 142 143 // invert priorities to avoid starvation seen in the component network 144 if (m_wakeups_wo_switch > PRIORITY_SWITCH_LIMIT) { 145 m_wakeups_wo_switch = 0; 146 highest_prio_vnet = 0; 147 lowest_prio_vnet = m_virtual_networks-1; 148 decrementer = -1; 149 } 150 151 // For all components incoming queues 152 for (int vnet = highest_prio_vnet; 153 (vnet * decrementer) >= (decrementer * lowest_prio_vnet); 154 vnet -= decrementer) { 155 156 // This is for round-robin scheduling 157 int incoming = m_round_robin_start; 158 m_round_robin_start++; 159 if (m_round_robin_start >= m_in.size()) { 160 m_round_robin_start = 0; 161 } 162 163 if(m_pending_message_count[vnet] > 0) { 164 // for all input ports, use round robin scheduling 165 for (int counter = 0; counter < m_in.size(); counter++) { 166 // Round robin scheduling 167 incoming++; 168 if (incoming >= m_in.size()) { 169 incoming = 0; 170 } 171 172 // temporary vectors to store the routing results 173 vector<LinkID> output_links; 174 vector<NetDest> output_link_destinations; 175 176 // Is there a message waiting? 177 while (m_in[incoming][vnet]->isReady()) { 178 DPRINTF(RubyNetwork, "incoming: %d\n", incoming); 179 180 // Peek at message 181 msg_ptr = m_in[incoming][vnet]->peekMsgPtr(); 182 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 183 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 184 185 output_links.clear(); 186 output_link_destinations.clear(); 187 NetDest msg_dsts = 188 net_msg_ptr->getInternalDestination(); 189 190 // Unfortunately, the token-protocol sends some 191 // zero-destination messages, so this assert isn't valid 192 // assert(msg_dsts.count() > 0); 193 194 assert(m_link_order.size() == m_routing_table.size()); 195 assert(m_link_order.size() == m_out.size()); 196 197 if (m_network_ptr->getAdaptiveRouting()) { 198 if (m_network_ptr->isVNetOrdered(vnet)) { 199 // Don't adaptively route 200 for (int out = 0; out < m_out.size(); out++) { 201 m_link_order[out].m_link = out; 202 m_link_order[out].m_value = 0; 203 } 204 } else { 205 // Find how clogged each link is 206 for (int out = 0; out < m_out.size(); out++) { 207 int out_queue_length = 0; 208 for (int v = 0; v < m_virtual_networks; v++) { 209 out_queue_length += m_out[out][v]->getSize(); 210 } 211 int value = 212 (out_queue_length << 8) | (random() & 0xff); 213 m_link_order[out].m_link = out; 214 m_link_order[out].m_value = value; 215 } 216 217 // Look at the most empty link first 218 sort(m_link_order.begin(), m_link_order.end()); 219 } 220 } 221 222 for (int i = 0; i < m_routing_table.size(); i++) { 223 // pick the next link to look at 224 int link = m_link_order[i].m_link; 225 NetDest dst = m_routing_table[link]; 226 DPRINTF(RubyNetwork, "dst: %s\n", dst); 227 228 if (!msg_dsts.intersectionIsNotEmpty(dst)) 229 continue; 230 231 // Remember what link we're using 232 output_links.push_back(link); 233 234 // Need to remember which destinations need this 235 // message in another vector. This Set is the 236 // intersection of the routing_table entry and the 237 // current destination set. The intersection must 238 // not be empty, since we are inside "if" 239 output_link_destinations.push_back(msg_dsts.AND(dst)); 240 241 // Next, we update the msg_destination not to 242 // include those nodes that were already handled 243 // by this link 244 msg_dsts.removeNetDest(dst); 245 } 246 247 assert(msg_dsts.count() == 0); 248 //assert(output_links.size() > 0); 249 250 // Check for resources - for all outgoing queues 251 bool enough = true; 252 for (int i = 0; i < output_links.size(); i++) { 253 int outgoing = output_links[i]; 254 if (!m_out[outgoing][vnet]->areNSlotsAvailable(1)) 255 enough = false; 256 DPRINTF(RubyNetwork, "Checking if node is blocked ..." 257 "outgoing: %d, vnet: %d, enough: %d\n", 258 outgoing, vnet, enough); 259 } 260 261 // There were not enough resources 262 if (!enough) { 263 g_eventQueue_ptr->scheduleEvent(this, 1); 264 DPRINTF(RubyNetwork, "Can't deliver message since a node " 265 "is blocked\n"); 266 DPRINTF(RubyNetwork, "Message: %s\n", (*net_msg_ptr)); 267 break; // go to next incoming port 268 } 269 270 MsgPtr unmodified_msg_ptr; 271 272 if (output_links.size() > 1) { 273 // If we are sending this message down more than 274 // one link (size>1), we need to make a copy of 275 // the message so each branch can have a different 276 // internal destination we need to create an 277 // unmodified MsgPtr because the MessageBuffer 278 // enqueue func will modify the message 279 280 // This magic line creates a private copy of the 281 // message 282 unmodified_msg_ptr = msg_ptr->clone(); 283 } 284 285 // Enqueue it - for all outgoing queues 286 for (int i=0; i<output_links.size(); i++) { 287 int outgoing = output_links[i]; 288 289 if (i > 0) { 290 // create a private copy of the unmodified 291 // message 292 msg_ptr = unmodified_msg_ptr->clone(); 293 } 294 295 // Change the internal destination set of the 296 // message so it knows which destinations this 297 // link is responsible for. 298 net_msg_ptr = safe_cast<NetworkMessage*>(msg_ptr.get()); 299 net_msg_ptr->getInternalDestination() = 300 output_link_destinations[i]; 301 302 // Enqeue msg 303 DPRINTF(RubyNetwork, "Enqueuing net msg from " 304 "inport[%d][%d] to outport [%d][%d].\n", 305 incoming, vnet, outgoing, vnet); 306 307 m_out[outgoing][vnet]->enqueue(msg_ptr); 308 } 309 310 // Dequeue msg 311 m_in[incoming][vnet]->pop(); 312 m_pending_message_count[vnet]--; 313 } 314 } 315 } 316 } 317} 318 319void 320PerfectSwitch::storeEventInfo(int info) 321{ 322 m_pending_message_count[info]++; 323} 324 325void 326PerfectSwitch::printStats(std::ostream& out) const 327{ 328 out << "PerfectSwitch printStats" << endl; 329} 330 331void 332PerfectSwitch::clearStats() 333{ 334} 335 336void 337PerfectSwitch::print(std::ostream& out) const 338{ 339 out << "[PerfectSwitch " << m_switch_id << "]"; 340} 341 342