MessageBuffer.cc revision 11797:f61fbb7ceb88
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 "mem/ruby/network/MessageBuffer.hh" 30 31#include <cassert> 32 33#include "base/cprintf.hh" 34#include "base/misc.hh" 35#include "base/random.hh" 36#include "base/stl_helpers.hh" 37#include "debug/RubyQueue.hh" 38#include "mem/ruby/system/RubySystem.hh" 39 40using namespace std; 41using m5::stl_helpers::operator<<; 42 43MessageBuffer::MessageBuffer(const Params *p) 44 : SimObject(p), m_stall_map_size(0), 45 m_max_size(p->buffer_size), m_time_last_time_size_checked(0), 46 m_time_last_time_enqueue(0), m_time_last_time_pop(0), 47 m_last_arrival_time(0), m_strict_fifo(p->ordered), 48 m_randomization(p->randomization) 49{ 50 m_msg_counter = 0; 51 m_consumer = NULL; 52 m_size_last_time_size_checked = 0; 53 m_size_at_cycle_start = 0; 54 m_msgs_this_cycle = 0; 55 m_priority_rank = 0; 56 57 m_stall_msg_map.clear(); 58 m_input_link_id = 0; 59 m_vnet_id = 0; 60 61 m_buf_msgs = 0; 62 m_stall_time = 0; 63 64 m_dequeue_callback = nullptr; 65} 66 67unsigned int 68MessageBuffer::getSize(Tick curTime) 69{ 70 if (m_time_last_time_size_checked != curTime) { 71 m_time_last_time_size_checked = curTime; 72 m_size_last_time_size_checked = m_prio_heap.size(); 73 } 74 75 return m_size_last_time_size_checked; 76} 77 78bool 79MessageBuffer::areNSlotsAvailable(unsigned int n, Tick current_time) 80{ 81 82 // fast path when message buffers have infinite size 83 if (m_max_size == 0) { 84 return true; 85 } 86 87 // determine the correct size for the current cycle 88 // pop operations shouldn't effect the network's visible size 89 // until schd cycle, but enqueue operations effect the visible 90 // size immediately 91 unsigned int current_size = 0; 92 93 if (m_time_last_time_pop < current_time) { 94 // no pops this cycle - heap size is correct 95 current_size = m_prio_heap.size(); 96 } else { 97 if (m_time_last_time_enqueue < current_time) { 98 // no enqueues this cycle - m_size_at_cycle_start is correct 99 current_size = m_size_at_cycle_start; 100 } else { 101 // both pops and enqueues occured this cycle - add new 102 // enqueued msgs to m_size_at_cycle_start 103 current_size = m_size_at_cycle_start + m_msgs_this_cycle; 104 } 105 } 106 107 // now compare the new size with our max size 108 if (current_size + m_stall_map_size + n <= m_max_size) { 109 return true; 110 } else { 111 DPRINTF(RubyQueue, "n: %d, current_size: %d, heap size: %d, " 112 "m_max_size: %d\n", 113 n, current_size, m_prio_heap.size(), m_max_size); 114 m_not_avail_count++; 115 return false; 116 } 117} 118 119const Message* 120MessageBuffer::peek() const 121{ 122 DPRINTF(RubyQueue, "Peeking at head of queue.\n"); 123 const Message* msg_ptr = m_prio_heap.front().get(); 124 assert(msg_ptr); 125 126 DPRINTF(RubyQueue, "Message: %s\n", (*msg_ptr)); 127 return msg_ptr; 128} 129 130// FIXME - move me somewhere else 131Tick 132random_time() 133{ 134 Tick time = 1; 135 time += random_mt.random(0, 3); // [0...3] 136 if (random_mt.random(0, 7) == 0) { // 1 in 8 chance 137 time += 100 + random_mt.random(1, 15); // 100 + [1...15] 138 } 139 return time; 140} 141 142void 143MessageBuffer::enqueue(MsgPtr message, Tick current_time, Tick delta) 144{ 145 // record current time incase we have a pop that also adjusts my size 146 if (m_time_last_time_enqueue < current_time) { 147 m_msgs_this_cycle = 0; // first msg this cycle 148 m_time_last_time_enqueue = current_time; 149 } 150 151 m_msg_counter++; 152 m_msgs_this_cycle++; 153 154 // Calculate the arrival time of the message, that is, the first 155 // cycle the message can be dequeued. 156 assert(delta > 0); 157 Tick arrival_time = 0; 158 159 if (!RubySystem::getRandomization() || !m_randomization) { 160 // No randomization 161 arrival_time = current_time + delta; 162 } else { 163 // Randomization - ignore delta 164 if (m_strict_fifo) { 165 if (m_last_arrival_time < current_time) { 166 m_last_arrival_time = current_time; 167 } 168 arrival_time = m_last_arrival_time + random_time(); 169 } else { 170 arrival_time = current_time + random_time(); 171 } 172 } 173 174 // Check the arrival time 175 assert(arrival_time > current_time); 176 if (m_strict_fifo) { 177 if (arrival_time < m_last_arrival_time) { 178 panic("FIFO ordering violated: %s name: %s current time: %d " 179 "delta: %d arrival_time: %d last arrival_time: %d\n", 180 *this, name(), current_time, delta, arrival_time, 181 m_last_arrival_time); 182 } 183 } 184 185 // If running a cache trace, don't worry about the last arrival checks 186 if (!RubySystem::getWarmupEnabled()) { 187 m_last_arrival_time = arrival_time; 188 } 189 190 // compute the delay cycles and set enqueue time 191 Message* msg_ptr = message.get(); 192 assert(msg_ptr != NULL); 193 194 assert(current_time >= msg_ptr->getLastEnqueueTime() && 195 "ensure we aren't dequeued early"); 196 197 msg_ptr->updateDelayedTicks(current_time); 198 msg_ptr->setLastEnqueueTime(arrival_time); 199 msg_ptr->setMsgCounter(m_msg_counter); 200 201 // Insert the message into the priority heap 202 m_prio_heap.push_back(message); 203 push_heap(m_prio_heap.begin(), m_prio_heap.end(), greater<MsgPtr>()); 204 // Increment the number of messages statistic 205 m_buf_msgs++; 206 207 DPRINTF(RubyQueue, "Enqueue arrival_time: %lld, Message: %s\n", 208 arrival_time, *(message.get())); 209 210 // Schedule the wakeup 211 assert(m_consumer != NULL); 212 m_consumer->scheduleEventAbsolute(arrival_time); 213 m_consumer->storeEventInfo(m_vnet_id); 214} 215 216Tick 217MessageBuffer::dequeue(Tick current_time, bool decrement_messages) 218{ 219 DPRINTF(RubyQueue, "Popping\n"); 220 assert(isReady(current_time)); 221 222 // get MsgPtr of the message about to be dequeued 223 MsgPtr message = m_prio_heap.front(); 224 225 // get the delay cycles 226 message->updateDelayedTicks(current_time); 227 Tick delay = message->getDelayedTicks(); 228 229 m_stall_time = curTick() - message->getTime(); 230 231 // record previous size and time so the current buffer size isn't 232 // adjusted until schd cycle 233 if (m_time_last_time_pop < current_time) { 234 m_size_at_cycle_start = m_prio_heap.size(); 235 m_time_last_time_pop = current_time; 236 } 237 238 pop_heap(m_prio_heap.begin(), m_prio_heap.end(), greater<MsgPtr>()); 239 m_prio_heap.pop_back(); 240 if (decrement_messages) { 241 // If the message will be removed from the queue, decrement the 242 // number of message in the queue. 243 m_buf_msgs--; 244 } 245 246 // if a dequeue callback was requested, call it now 247 if (m_dequeue_callback) { 248 m_dequeue_callback(); 249 } 250 251 return delay; 252} 253 254void 255MessageBuffer::registerDequeueCallback(std::function<void()> callback) 256{ 257 m_dequeue_callback = callback; 258} 259 260void 261MessageBuffer::unregisterDequeueCallback() 262{ 263 m_dequeue_callback = nullptr; 264} 265 266void 267MessageBuffer::clear() 268{ 269 m_prio_heap.clear(); 270 271 m_msg_counter = 0; 272 m_time_last_time_enqueue = 0; 273 m_time_last_time_pop = 0; 274 m_size_at_cycle_start = 0; 275 m_msgs_this_cycle = 0; 276} 277 278void 279MessageBuffer::recycle(Tick current_time, Tick recycle_latency) 280{ 281 DPRINTF(RubyQueue, "Recycling.\n"); 282 assert(isReady(current_time)); 283 MsgPtr node = m_prio_heap.front(); 284 pop_heap(m_prio_heap.begin(), m_prio_heap.end(), greater<MsgPtr>()); 285 286 Tick future_time = current_time + recycle_latency; 287 node->setLastEnqueueTime(future_time); 288 289 m_prio_heap.back() = node; 290 push_heap(m_prio_heap.begin(), m_prio_heap.end(), greater<MsgPtr>()); 291 m_consumer->scheduleEventAbsolute(future_time); 292} 293 294void 295MessageBuffer::reanalyzeList(list<MsgPtr> <, Tick schdTick) 296{ 297 while (!lt.empty()) { 298 m_msg_counter++; 299 MsgPtr m = lt.front(); 300 m->setLastEnqueueTime(schdTick); 301 m->setMsgCounter(m_msg_counter); 302 303 m_prio_heap.push_back(m); 304 push_heap(m_prio_heap.begin(), m_prio_heap.end(), 305 greater<MsgPtr>()); 306 307 m_consumer->scheduleEventAbsolute(schdTick); 308 lt.pop_front(); 309 } 310} 311 312void 313MessageBuffer::reanalyzeMessages(Addr addr, Tick current_time) 314{ 315 DPRINTF(RubyQueue, "ReanalyzeMessages %#x\n", addr); 316 assert(m_stall_msg_map.count(addr) > 0); 317 318 // 319 // Put all stalled messages associated with this address back on the 320 // prio heap. The reanalyzeList call will make sure the consumer is 321 // scheduled for the current cycle so that the previously stalled messages 322 // will be observed before any younger messages that may arrive this cycle 323 // 324 m_stall_map_size -= m_stall_msg_map[addr].size(); 325 assert(m_stall_map_size >= 0); 326 reanalyzeList(m_stall_msg_map[addr], current_time); 327 m_stall_msg_map.erase(addr); 328} 329 330void 331MessageBuffer::reanalyzeAllMessages(Tick current_time) 332{ 333 DPRINTF(RubyQueue, "ReanalyzeAllMessages\n"); 334 335 // 336 // Put all stalled messages associated with this address back on the 337 // prio heap. The reanalyzeList call will make sure the consumer is 338 // scheduled for the current cycle so that the previously stalled messages 339 // will be observed before any younger messages that may arrive this cycle. 340 // 341 for (StallMsgMapType::iterator map_iter = m_stall_msg_map.begin(); 342 map_iter != m_stall_msg_map.end(); ++map_iter) { 343 m_stall_map_size -= map_iter->second.size(); 344 assert(m_stall_map_size >= 0); 345 reanalyzeList(map_iter->second, current_time); 346 } 347 m_stall_msg_map.clear(); 348} 349 350void 351MessageBuffer::stallMessage(Addr addr, Tick current_time) 352{ 353 DPRINTF(RubyQueue, "Stalling due to %#x\n", addr); 354 assert(isReady(current_time)); 355 assert(getOffset(addr) == 0); 356 MsgPtr message = m_prio_heap.front(); 357 358 // Since the message will just be moved to stall map, indicate that the 359 // buffer should not decrement the m_buf_msgs statistic 360 dequeue(current_time, false); 361 362 // 363 // Note: no event is scheduled to analyze the map at a later time. 364 // Instead the controller is responsible to call reanalyzeMessages when 365 // these addresses change state. 366 // 367 (m_stall_msg_map[addr]).push_back(message); 368 m_stall_map_size++; 369 m_stall_count++; 370} 371 372void 373MessageBuffer::print(ostream& out) const 374{ 375 ccprintf(out, "[MessageBuffer: "); 376 if (m_consumer != NULL) { 377 ccprintf(out, " consumer-yes "); 378 } 379 380 vector<MsgPtr> copy(m_prio_heap); 381 sort_heap(copy.begin(), copy.end(), greater<MsgPtr>()); 382 ccprintf(out, "%s] %s", copy, name()); 383} 384 385bool 386MessageBuffer::isReady(Tick current_time) const 387{ 388 return ((m_prio_heap.size() > 0) && 389 (m_prio_heap.front()->getLastEnqueueTime() <= current_time)); 390} 391 392void 393MessageBuffer::regStats() 394{ 395 m_not_avail_count 396 .name(name() + ".not_avail_count") 397 .desc("Number of times this buffer did not have N slots available") 398 .flags(Stats::nozero); 399 400 m_buf_msgs 401 .name(name() + ".avg_buf_msgs") 402 .desc("Average number of messages in buffer") 403 .flags(Stats::nozero); 404 405 m_stall_count 406 .name(name() + ".num_msg_stalls") 407 .desc("Number of times messages were stalled") 408 .flags(Stats::nozero); 409 410 m_occupancy 411 .name(name() + ".avg_buf_occ") 412 .desc("Average occupancy of buffer capacity") 413 .flags(Stats::nozero); 414 415 m_stall_time 416 .name(name() + ".avg_stall_time") 417 .desc("Average number of cycles messages are stalled in this MB") 418 .flags(Stats::nozero); 419 420 if (m_max_size > 0) { 421 m_occupancy = m_buf_msgs / m_max_size; 422 } else { 423 m_occupancy = 0; 424 } 425} 426 427uint32_t 428MessageBuffer::functionalWrite(Packet *pkt) 429{ 430 uint32_t num_functional_writes = 0; 431 432 // Check the priority heap and write any messages that may 433 // correspond to the address in the packet. 434 for (unsigned int i = 0; i < m_prio_heap.size(); ++i) { 435 Message *msg = m_prio_heap[i].get(); 436 if (msg->functionalWrite(pkt)) { 437 num_functional_writes++; 438 } 439 } 440 441 // Check the stall queue and write any messages that may 442 // correspond to the address in the packet. 443 for (StallMsgMapType::iterator map_iter = m_stall_msg_map.begin(); 444 map_iter != m_stall_msg_map.end(); 445 ++map_iter) { 446 447 for (std::list<MsgPtr>::iterator it = (map_iter->second).begin(); 448 it != (map_iter->second).end(); ++it) { 449 450 Message *msg = (*it).get(); 451 if (msg->functionalWrite(pkt)) { 452 num_functional_writes++; 453 } 454 } 455 } 456 457 return num_functional_writes; 458} 459 460MessageBuffer * 461MessageBufferParams::create() 462{ 463 return new MessageBuffer(this); 464} 465