mshr_queue.cc revision 11278:18411ccc4f3c
1/* 2 * Copyright (c) 2012-2013, 2015 ARM Limited 3 * All rights reserved. 4 * 5 * The license below extends only to copyright in the software and shall 6 * not be construed as granting a license to any other intellectual 7 * property including but not limited to intellectual property relating 8 * to a hardware implementation of the functionality of the software 9 * licensed hereunder. You may use the software subject to the license 10 * terms below provided that you ensure that this notice is replicated 11 * unmodified and in its entirety in all distributions of the software, 12 * modified or unmodified, in source code or in binary form. 13 * 14 * Copyright (c) 2003-2005 The Regents of The University of Michigan 15 * All rights reserved. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions are 19 * met: redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer; 21 * redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution; 24 * neither the name of the copyright holders nor the names of its 25 * contributors may be used to endorse or promote products derived from 26 * this software without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 39 * 40 * Authors: Erik Hallnor 41 * Andreas Sandberg 42 */ 43 44/** @file 45 * Definition of MSHRQueue class functions. 46 */ 47 48#include "base/trace.hh" 49#include "mem/cache/mshr_queue.hh" 50#include "debug/Drain.hh" 51 52using namespace std; 53 54MSHRQueue::MSHRQueue(const std::string &_label, 55 int num_entries, int reserve, int demand_reserve, 56 int _index) 57 : label(_label), numEntries(num_entries + reserve - 1), 58 numReserve(reserve), demandReserve(demand_reserve), 59 registers(numEntries), allocated(0), 60 inServiceEntries(0), index(_index) 61{ 62 for (int i = 0; i < numEntries; ++i) { 63 registers[i].queue = this; 64 freeList.push_back(®isters[i]); 65 } 66} 67 68MSHR * 69MSHRQueue::findMatch(Addr blk_addr, bool is_secure) const 70{ 71 for (const auto& mshr : allocatedList) { 72 // we ignore any MSHRs allocated for uncacheable accesses and 73 // simply ignore them when matching, in the cache we never 74 // check for matches when adding new uncacheable entries, and 75 // we do not want normal cacheable accesses being added to an 76 // MSHR serving an uncacheable access 77 if (!mshr->isUncacheable() && mshr->blkAddr == blk_addr && 78 mshr->isSecure == is_secure) { 79 return mshr; 80 } 81 } 82 return NULL; 83} 84 85bool 86MSHRQueue::findMatches(Addr blk_addr, bool is_secure, 87 vector<MSHR*>& matches) const 88{ 89 // Need an empty vector 90 assert(matches.empty()); 91 bool retval = false; 92 for (const auto& mshr : allocatedList) { 93 if (!mshr->isUncacheable() && mshr->blkAddr == blk_addr && 94 mshr->isSecure == is_secure) { 95 retval = true; 96 matches.push_back(mshr); 97 } 98 } 99 return retval; 100} 101 102 103bool 104MSHRQueue::checkFunctional(PacketPtr pkt, Addr blk_addr) 105{ 106 pkt->pushLabel(label); 107 for (const auto& mshr : allocatedList) { 108 if (mshr->blkAddr == blk_addr && mshr->checkFunctional(pkt)) { 109 pkt->popLabel(); 110 return true; 111 } 112 } 113 pkt->popLabel(); 114 return false; 115} 116 117 118MSHR * 119MSHRQueue::findPending(Addr blk_addr, bool is_secure) const 120{ 121 for (const auto& mshr : readyList) { 122 if (mshr->blkAddr == blk_addr && mshr->isSecure == is_secure) { 123 return mshr; 124 } 125 } 126 return NULL; 127} 128 129 130MSHR::Iterator 131MSHRQueue::addToReadyList(MSHR *mshr) 132{ 133 if (readyList.empty() || readyList.back()->readyTime <= mshr->readyTime) { 134 return readyList.insert(readyList.end(), mshr); 135 } 136 137 for (auto i = readyList.begin(); i != readyList.end(); ++i) { 138 if ((*i)->readyTime > mshr->readyTime) { 139 return readyList.insert(i, mshr); 140 } 141 } 142 assert(false); 143 return readyList.end(); // keep stupid compilers happy 144} 145 146 147MSHR * 148MSHRQueue::allocate(Addr blk_addr, unsigned blk_size, PacketPtr pkt, 149 Tick when_ready, Counter order, bool alloc_on_fill) 150{ 151 assert(!freeList.empty()); 152 MSHR *mshr = freeList.front(); 153 assert(mshr->getNumTargets() == 0); 154 freeList.pop_front(); 155 156 mshr->allocate(blk_addr, blk_size, pkt, when_ready, order, alloc_on_fill); 157 mshr->allocIter = allocatedList.insert(allocatedList.end(), mshr); 158 mshr->readyIter = addToReadyList(mshr); 159 160 allocated += 1; 161 return mshr; 162} 163 164 165void 166MSHRQueue::deallocate(MSHR *mshr) 167{ 168 deallocateOne(mshr); 169} 170 171MSHR::Iterator 172MSHRQueue::deallocateOne(MSHR *mshr) 173{ 174 MSHR::Iterator retval = allocatedList.erase(mshr->allocIter); 175 freeList.push_front(mshr); 176 allocated--; 177 if (mshr->inService) { 178 inServiceEntries--; 179 } else { 180 readyList.erase(mshr->readyIter); 181 } 182 mshr->deallocate(); 183 if (drainState() == DrainState::Draining && allocated == 0) { 184 // Notify the drain manager that we have completed draining if 185 // there are no other outstanding requests in this MSHR queue. 186 DPRINTF(Drain, "MSHRQueue now empty, signalling drained\n"); 187 signalDrainDone(); 188 } 189 return retval; 190} 191 192void 193MSHRQueue::moveToFront(MSHR *mshr) 194{ 195 if (!mshr->inService) { 196 assert(mshr == *(mshr->readyIter)); 197 readyList.erase(mshr->readyIter); 198 mshr->readyIter = readyList.insert(readyList.begin(), mshr); 199 } 200} 201 202void 203MSHRQueue::markInService(MSHR *mshr, bool pending_dirty_resp) 204{ 205 if (mshr->markInService(pending_dirty_resp)) { 206 deallocate(mshr); 207 } else { 208 readyList.erase(mshr->readyIter); 209 inServiceEntries += 1; 210 } 211} 212 213void 214MSHRQueue::markPending(MSHR *mshr) 215{ 216 assert(mshr->inService); 217 mshr->inService = false; 218 --inServiceEntries; 219 /** 220 * @ todo might want to add rerequests to front of pending list for 221 * performance. 222 */ 223 mshr->readyIter = addToReadyList(mshr); 224} 225 226bool 227MSHRQueue::forceDeallocateTarget(MSHR *mshr) 228{ 229 bool was_full = isFull(); 230 assert(mshr->hasTargets()); 231 // Pop the prefetch off of the target list 232 mshr->popTarget(); 233 // Delete mshr if no remaining targets 234 if (!mshr->hasTargets() && !mshr->promoteDeferredTargets()) { 235 deallocateOne(mshr); 236 } 237 238 // Notify if MSHR queue no longer full 239 return was_full && !isFull(); 240} 241 242DrainState 243MSHRQueue::drain() 244{ 245 return allocated == 0 ? DrainState::Drained : DrainState::Draining; 246} 247