packet_queue.cc revision 10745
12914SN/A/* 210713Sandreas.hansson@arm.com * Copyright (c) 2012,2015 ARM Limited 38856SN/A * All rights reserved. 48856SN/A * 58856SN/A * The license below extends only to copyright in the software and shall 68856SN/A * not be construed as granting a license to any other intellectual 78856SN/A * property including but not limited to intellectual property relating 88856SN/A * to a hardware implementation of the functionality of the software 98856SN/A * licensed hereunder. You may use the software subject to the license 108856SN/A * terms below provided that you ensure that this notice is replicated 118856SN/A * unmodified and in its entirety in all distributions of the software, 128856SN/A * modified or unmodified, in source code or in binary form. 138856SN/A * 142914SN/A * Copyright (c) 2006 The Regents of The University of Michigan 152914SN/A * All rights reserved. 162914SN/A * 172914SN/A * Redistribution and use in source and binary forms, with or without 182914SN/A * modification, are permitted provided that the following conditions are 192914SN/A * met: redistributions of source code must retain the above copyright 202914SN/A * notice, this list of conditions and the following disclaimer; 212914SN/A * redistributions in binary form must reproduce the above copyright 222914SN/A * notice, this list of conditions and the following disclaimer in the 232914SN/A * documentation and/or other materials provided with the distribution; 242914SN/A * neither the name of the copyright holders nor the names of its 252914SN/A * contributors may be used to endorse or promote products derived from 262914SN/A * this software without specific prior written permission. 272914SN/A * 282914SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 292914SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 302914SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 312914SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 322914SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 332914SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 342914SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 352914SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 362914SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 372914SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 382914SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 392914SN/A * 402914SN/A * Authors: Ali Saidi 418856SN/A * Andreas Hansson 422914SN/A */ 432914SN/A 449356Snilay@cs.wisc.edu#include "base/trace.hh" 459152Satgutier@umich.edu#include "debug/Drain.hh" 468914Sandreas.hansson@arm.com#include "debug/PacketQueue.hh" 478914Sandreas.hansson@arm.com#include "mem/packet_queue.hh" 482914SN/A 495740SN/Ausing namespace std; 505740SN/A 518975Sandreas.hansson@arm.comPacketQueue::PacketQueue(EventManager& _em, const std::string& _label) 529342SAndreas.Sandberg@arm.com : em(_em), sendEvent(this), drainManager(NULL), label(_label), 535740SN/A waitingOnRetry(false) 545740SN/A{ 555740SN/A} 565740SN/A 578914Sandreas.hansson@arm.comPacketQueue::~PacketQueue() 585740SN/A{ 595740SN/A} 605740SN/A 618914Sandreas.hansson@arm.comvoid 628914Sandreas.hansson@arm.comPacketQueue::retry() 638914Sandreas.hansson@arm.com{ 648914Sandreas.hansson@arm.com DPRINTF(PacketQueue, "Queue %s received retry\n", name()); 658914Sandreas.hansson@arm.com assert(waitingOnRetry); 6610713Sandreas.hansson@arm.com waitingOnRetry = false; 678914Sandreas.hansson@arm.com sendDeferredPacket(); 688914Sandreas.hansson@arm.com} 698914Sandreas.hansson@arm.com 704929SN/Abool 7110713Sandreas.hansson@arm.comPacketQueue::hasAddr(Addr addr) const 7210713Sandreas.hansson@arm.com{ 7310713Sandreas.hansson@arm.com // caller is responsible for ensuring that all packets have the 7410713Sandreas.hansson@arm.com // same alignment 7510713Sandreas.hansson@arm.com for (const auto& p : transmitList) { 7610713Sandreas.hansson@arm.com if (p.pkt->getAddr() == addr) 7710713Sandreas.hansson@arm.com return true; 7810713Sandreas.hansson@arm.com } 7910713Sandreas.hansson@arm.com return false; 8010713Sandreas.hansson@arm.com} 8110713Sandreas.hansson@arm.com 8210713Sandreas.hansson@arm.combool 838914Sandreas.hansson@arm.comPacketQueue::checkFunctional(PacketPtr pkt) 843091SN/A{ 858856SN/A pkt->pushLabel(label); 868856SN/A 8710322Sandreas.hansson@arm.com auto i = transmitList.begin(); 888856SN/A bool found = false; 893296SN/A 9010322Sandreas.hansson@arm.com while (!found && i != transmitList.end()) { 918856SN/A // If the buffered packet contains data, and it overlaps the 928856SN/A // current packet, then update data 938856SN/A found = pkt->checkFunctional(i->pkt); 948856SN/A ++i; 953284SN/A } 964929SN/A 978856SN/A pkt->popLabel(); 988856SN/A 998856SN/A return found; 1004490SN/A} 1013342SN/A 1024490SN/Avoid 10310722Sstephan.diestelhorst@arm.comPacketQueue::schedSendTiming(PacketPtr pkt, Tick when, bool force_order) 1043403SN/A{ 10510722Sstephan.diestelhorst@arm.com DPRINTF(PacketQueue, "%s for %s address %x size %d when %lu ord: %i\n", 10610722Sstephan.diestelhorst@arm.com __func__, pkt->cmdString(), pkt->getAddr(), pkt->getSize(), when, 10710722Sstephan.diestelhorst@arm.com force_order); 10810713Sandreas.hansson@arm.com 1099160Sandreas.hansson@arm.com // we can still send a packet before the end of this tick 1109160Sandreas.hansson@arm.com assert(when >= curTick()); 1114492SN/A 1129163Sandreas.hansson@arm.com // express snoops should never be queued 1139163Sandreas.hansson@arm.com assert(!pkt->isExpressSnoop()); 1149163Sandreas.hansson@arm.com 1159390Sandreas.hansson@arm.com // add a very basic sanity check on the port to ensure the 1169390Sandreas.hansson@arm.com // invisible buffer is not growing beyond reasonable limits 1179390Sandreas.hansson@arm.com if (transmitList.size() > 100) { 1189390Sandreas.hansson@arm.com panic("Packet queue %s has grown beyond 100 packets\n", 1199390Sandreas.hansson@arm.com name()); 1209390Sandreas.hansson@arm.com } 1219390Sandreas.hansson@arm.com 12210722Sstephan.diestelhorst@arm.com // if requested, force the timing to be in-order by changing the when 12310722Sstephan.diestelhorst@arm.com // parameter 12410722Sstephan.diestelhorst@arm.com if (force_order && !transmitList.empty()) { 12510722Sstephan.diestelhorst@arm.com Tick back = transmitList.back().tick; 12610722Sstephan.diestelhorst@arm.com 12710722Sstephan.diestelhorst@arm.com // fudge timing if required; relies on the code below to do the right 12810722Sstephan.diestelhorst@arm.com // thing (push_back) with the updated time-stamp 12910722Sstephan.diestelhorst@arm.com if (when < back) { 13010722Sstephan.diestelhorst@arm.com DPRINTF(PacketQueue, "%s force_order shifted packet %s address "\ 13110722Sstephan.diestelhorst@arm.com "%x from %lu to %lu\n", __func__, pkt->cmdString(), 13210722Sstephan.diestelhorst@arm.com pkt->getAddr(), when, back); 13310722Sstephan.diestelhorst@arm.com when = back; 13410722Sstephan.diestelhorst@arm.com } 13510722Sstephan.diestelhorst@arm.com } 13610722Sstephan.diestelhorst@arm.com 1378914Sandreas.hansson@arm.com // nothing on the list, or earlier than current front element, 1388914Sandreas.hansson@arm.com // schedule an event 1394666SN/A if (transmitList.empty() || when < transmitList.front().tick) { 14010722Sstephan.diestelhorst@arm.com // force_order-ed in here only when list is empty 14110722Sstephan.diestelhorst@arm.com assert(!force_order || transmitList.empty()); 1428914Sandreas.hansson@arm.com // note that currently we ignore a potentially outstanding retry 1438914Sandreas.hansson@arm.com // and could in theory put a new packet at the head of the 1448914Sandreas.hansson@arm.com // transmit list before retrying the existing packet 14510745Sandreas.hansson@arm.com transmitList.emplace_front(DeferredPacket(when, pkt)); 1464666SN/A schedSendEvent(when); 1474666SN/A return; 1484666SN/A } 1494666SN/A 15010713Sandreas.hansson@arm.com // we should either have an outstanding retry, or a send event 15110713Sandreas.hansson@arm.com // scheduled, but there is an unfortunate corner case where the 15210713Sandreas.hansson@arm.com // x86 page-table walker and timing CPU send out a new request as 15310713Sandreas.hansson@arm.com // part of the receiving of a response (called by 15410713Sandreas.hansson@arm.com // PacketQueue::sendDeferredPacket), in which we end up calling 15510713Sandreas.hansson@arm.com // ourselves again before we had a chance to update waitingOnRetry 15610713Sandreas.hansson@arm.com // assert(waitingOnRetry || sendEvent.scheduled()); 15710713Sandreas.hansson@arm.com 1588914Sandreas.hansson@arm.com // list is non-empty and this belongs at the end 1594666SN/A if (when >= transmitList.back().tick) { 16010745Sandreas.hansson@arm.com transmitList.emplace_back(DeferredPacket(when, pkt)); 1613450SN/A return; 1623403SN/A } 1633450SN/A 16410722Sstephan.diestelhorst@arm.com // forced orders never need insertion in the middle 16510722Sstephan.diestelhorst@arm.com assert(!force_order); 16610722Sstephan.diestelhorst@arm.com 1678914Sandreas.hansson@arm.com // this belongs in the middle somewhere, insertion sort 16810322Sandreas.hansson@arm.com auto i = transmitList.begin(); 1698914Sandreas.hansson@arm.com ++i; // already checked for insertion at front 1708914Sandreas.hansson@arm.com while (i != transmitList.end() && when >= i->tick) 1718914Sandreas.hansson@arm.com ++i; 17210745Sandreas.hansson@arm.com transmitList.emplace(i, DeferredPacket(when, pkt)); 1738856SN/A} 1748856SN/A 1758856SN/Avoid 17610713Sandreas.hansson@arm.comPacketQueue::schedSendEvent(Tick when) 1778856SN/A{ 17810713Sandreas.hansson@arm.com // if we are waiting on a retry just hold off 17910713Sandreas.hansson@arm.com if (waitingOnRetry) { 18010713Sandreas.hansson@arm.com DPRINTF(PacketQueue, "Not scheduling send as waiting for retry\n"); 18110713Sandreas.hansson@arm.com assert(!sendEvent.scheduled()); 18210713Sandreas.hansson@arm.com return; 18310713Sandreas.hansson@arm.com } 1848914Sandreas.hansson@arm.com 18510713Sandreas.hansson@arm.com if (when != MaxTick) { 18610713Sandreas.hansson@arm.com // we cannot go back in time, and to be consistent we stick to 18710713Sandreas.hansson@arm.com // one tick in the future 18810713Sandreas.hansson@arm.com when = std::max(when, curTick() + 1); 18910713Sandreas.hansson@arm.com // @todo Revisit the +1 19010713Sandreas.hansson@arm.com 19110423Sandreas.hansson@arm.com if (!sendEvent.scheduled()) { 19210713Sandreas.hansson@arm.com em.schedule(&sendEvent, when); 19310713Sandreas.hansson@arm.com } else if (when < sendEvent.when()) { 19410423Sandreas.hansson@arm.com // if the new time is earlier than when the event 19510423Sandreas.hansson@arm.com // currently is scheduled, move it forward 19610713Sandreas.hansson@arm.com em.reschedule(&sendEvent, when); 19710423Sandreas.hansson@arm.com } 1988856SN/A } else { 19910713Sandreas.hansson@arm.com // we get a MaxTick when there is no more to send, so if we're 20010713Sandreas.hansson@arm.com // draining, we may be done at this point 2019342SAndreas.Sandberg@arm.com if (drainManager && transmitList.empty() && !sendEvent.scheduled()) { 2029152Satgutier@umich.edu DPRINTF(Drain, "PacketQueue done draining," 2039152Satgutier@umich.edu "processing drain event\n"); 2049342SAndreas.Sandberg@arm.com drainManager->signalDrainDone(); 2059342SAndreas.Sandberg@arm.com drainManager = NULL; 2068856SN/A } 2078856SN/A } 2088856SN/A} 2094492SN/A 2103403SN/Avoid 2118914Sandreas.hansson@arm.comPacketQueue::sendDeferredPacket() 2122914SN/A{ 21310713Sandreas.hansson@arm.com // sanity checks 21410713Sandreas.hansson@arm.com assert(!waitingOnRetry); 21510713Sandreas.hansson@arm.com assert(deferredPacketReady()); 21610713Sandreas.hansson@arm.com 21710713Sandreas.hansson@arm.com DeferredPacket dp = transmitList.front(); 21810713Sandreas.hansson@arm.com 21910713Sandreas.hansson@arm.com // take the packet of the list before sending it, as sending of 22010713Sandreas.hansson@arm.com // the packet in some cases causes a new packet to be enqueued 22110713Sandreas.hansson@arm.com // (most notaly when responding to the timing CPU, leading to a 22210713Sandreas.hansson@arm.com // new request hitting in the L1 icache, leading to a new 22310713Sandreas.hansson@arm.com // response) 22410713Sandreas.hansson@arm.com transmitList.pop_front(); 22510713Sandreas.hansson@arm.com 22610713Sandreas.hansson@arm.com // use the appropriate implementation of sendTiming based on the 22710713Sandreas.hansson@arm.com // type of queue 22810713Sandreas.hansson@arm.com waitingOnRetry = !sendTiming(dp.pkt); 2294492SN/A 2308856SN/A // if we succeeded and are not waiting for a retry, schedule the 2318856SN/A // next send 2328856SN/A if (!waitingOnRetry) { 23310713Sandreas.hansson@arm.com schedSendEvent(deferredPacketReadyTime()); 23410713Sandreas.hansson@arm.com } else { 23510713Sandreas.hansson@arm.com // put the packet back at the front of the list 23610745Sandreas.hansson@arm.com transmitList.emplace_front(dp); 2374492SN/A } 2384492SN/A} 2394492SN/A 2404492SN/Avoid 2418914Sandreas.hansson@arm.comPacketQueue::processSendEvent() 2424492SN/A{ 2434492SN/A assert(!waitingOnRetry); 2444492SN/A sendDeferredPacket(); 2452914SN/A} 2462914SN/A 2472914SN/Aunsigned int 2489342SAndreas.Sandberg@arm.comPacketQueue::drain(DrainManager *dm) 2492914SN/A{ 25010322Sandreas.hansson@arm.com if (transmitList.empty()) 2512914SN/A return 0; 2529152Satgutier@umich.edu DPRINTF(Drain, "PacketQueue not drained\n"); 2539342SAndreas.Sandberg@arm.com drainManager = dm; 2542914SN/A return 1; 2552914SN/A} 2568975Sandreas.hansson@arm.com 25710713Sandreas.hansson@arm.comReqPacketQueue::ReqPacketQueue(EventManager& _em, MasterPort& _masterPort, 25810713Sandreas.hansson@arm.com const std::string _label) 2598975Sandreas.hansson@arm.com : PacketQueue(_em, _label), masterPort(_masterPort) 2608975Sandreas.hansson@arm.com{ 2618975Sandreas.hansson@arm.com} 2628975Sandreas.hansson@arm.com 2638975Sandreas.hansson@arm.combool 26410713Sandreas.hansson@arm.comReqPacketQueue::sendTiming(PacketPtr pkt) 2658975Sandreas.hansson@arm.com{ 26610713Sandreas.hansson@arm.com return masterPort.sendTimingReq(pkt); 2678975Sandreas.hansson@arm.com} 2688975Sandreas.hansson@arm.com 26910713Sandreas.hansson@arm.comSnoopRespPacketQueue::SnoopRespPacketQueue(EventManager& _em, 27010713Sandreas.hansson@arm.com MasterPort& _masterPort, 27110713Sandreas.hansson@arm.com const std::string _label) 27210713Sandreas.hansson@arm.com : PacketQueue(_em, _label), masterPort(_masterPort) 27310713Sandreas.hansson@arm.com{ 27410713Sandreas.hansson@arm.com} 27510713Sandreas.hansson@arm.com 27610713Sandreas.hansson@arm.combool 27710713Sandreas.hansson@arm.comSnoopRespPacketQueue::sendTiming(PacketPtr pkt) 27810713Sandreas.hansson@arm.com{ 27910713Sandreas.hansson@arm.com return masterPort.sendTimingSnoopResp(pkt); 28010713Sandreas.hansson@arm.com} 28110713Sandreas.hansson@arm.com 28210713Sandreas.hansson@arm.comRespPacketQueue::RespPacketQueue(EventManager& _em, SlavePort& _slavePort, 28310713Sandreas.hansson@arm.com const std::string _label) 2848975Sandreas.hansson@arm.com : PacketQueue(_em, _label), slavePort(_slavePort) 2858975Sandreas.hansson@arm.com{ 2868975Sandreas.hansson@arm.com} 2878975Sandreas.hansson@arm.com 2888975Sandreas.hansson@arm.combool 28910713Sandreas.hansson@arm.comRespPacketQueue::sendTiming(PacketPtr pkt) 2908975Sandreas.hansson@arm.com{ 2918975Sandreas.hansson@arm.com return slavePort.sendTimingResp(pkt); 2928975Sandreas.hansson@arm.com} 293