diff options
| -rw-r--r-- | src/dev/etherlink.cc | 138 | ||||
| -rw-r--r-- | src/dev/etherlink.hh | 48 |
2 files changed, 100 insertions, 86 deletions
diff --git a/src/dev/etherlink.cc b/src/dev/etherlink.cc index 7b24fe9f7..1c88a31dd 100644 --- a/src/dev/etherlink.cc +++ b/src/dev/etherlink.cc @@ -1,4 +1,16 @@ /* + * Copyright (c) 2015 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * * Copyright (c) 2002-2005 The Regents of The University of Michigan * All rights reserved. * @@ -103,7 +115,7 @@ EtherLink::Link::Link(const string &name, EtherLink *p, int num, double rate, Tick delay, Tick delay_var, EtherDump *d) : objName(name), parent(p), number(num), txint(NULL), rxint(NULL), ticksPerByte(rate), linkDelay(delay), delayVar(delay_var), dump(d), - doneEvent(this) + doneEvent(this), txQueueEvent(this) { } void @@ -128,25 +140,6 @@ EtherLink::Link::txComplete(EthPacketPtr packet) rxint->sendPacket(packet); } -class LinkDelayEvent : public Event -{ - protected: - EtherLink::Link *link; - EthPacketPtr packet; - - public: - // non-scheduling version for createForUnserialize() - LinkDelayEvent(); - LinkDelayEvent(EtherLink::Link *link, EthPacketPtr pkt); - - void process(); - - void serialize(CheckpointOut &cp) const M5_ATTR_OVERRIDE; - void unserialize(CheckpointIn &cp) M5_ATTR_OVERRIDE; - static Serializable *createForUnserialize(CheckpointIn &cp, - const string §ion); -}; - void EtherLink::Link::txDone() { @@ -155,9 +148,11 @@ EtherLink::Link::txDone() if (linkDelay > 0) { DPRINTF(Ethernet, "packet delayed: delay=%d\n", linkDelay); - Event *event = new LinkDelayEvent(this, packet); - parent->schedule(event, curTick() + linkDelay); + txQueue.emplace_back(std::make_pair(curTick() + linkDelay, packet)); + if (!txQueueEvent.scheduled()) + parent->schedule(txQueueEvent, txQueue.front().first); } else { + assert(txQueue.empty()); txComplete(packet); } @@ -167,6 +162,23 @@ EtherLink::Link::txDone() txint->sendDone(); } +void +EtherLink::Link::processTxQueue() +{ + auto cur(txQueue.front()); + txQueue.pop_front(); + + // Schedule a new event to process the next packet in the queue. + if (!txQueue.empty()) { + auto next(txQueue.front()); + assert(next.first > curTick()); + parent->schedule(txQueueEvent, next.first); + } + + assert(cur.first == curTick()); + txComplete(cur.second); +} + bool EtherLink::Link::transmit(EthPacketPtr pkt) { @@ -205,6 +217,15 @@ EtherLink::Link::serialize(const string &base, CheckpointOut &cp) const paramOut(cp, base + ".event_time", event_time); } + const size_t tx_queue_size(txQueue.size()); + paramOut(cp, base + ".tx_queue_size", tx_queue_size); + unsigned idx(0); + for (const auto &pe : txQueue) { + paramOut(cp, csprintf("%s.txQueue[%i].tick", base, idx), pe.first); + pe.second->serialize(csprintf("%s.txQueue[%i].packet", base, idx), cp); + + ++idx; + } } void @@ -224,64 +245,33 @@ EtherLink::Link::unserialize(const string &base, CheckpointIn &cp) paramIn(cp, base + ".event_time", event_time); parent->schedule(doneEvent, event_time); } -} - -LinkDelayEvent::LinkDelayEvent() - : Event(Default_Pri, AutoSerialize | AutoDelete), link(NULL) -{ -} - -LinkDelayEvent::LinkDelayEvent(EtherLink::Link *l, EthPacketPtr p) - : Event(Default_Pri, AutoSerialize | AutoDelete), link(l), packet(p) -{ -} -void -LinkDelayEvent::process() -{ - link->txComplete(packet); -} + size_t tx_queue_size; + if (optParamIn(cp, base + ".tx_queue_size", tx_queue_size)) { + for (size_t idx = 0; idx < tx_queue_size; ++idx) { + Tick tick; + EthPacketPtr delayed_packet = make_shared<EthPacketData>(16384); -void -LinkDelayEvent::serialize(CheckpointOut &cp) const -{ - paramOut(cp, "type", string("LinkDelayEvent")); - Event::serialize(cp); + paramIn(cp, csprintf("%s.txQueue[%i].tick", base, idx), tick); + delayed_packet->unserialize( + csprintf("%s.txQueue[%i].packet", base, idx), cp); - EtherLink *parent = link->parent; - bool number = link->number; - SERIALIZE_OBJPTR(parent); - SERIALIZE_SCALAR(number); + fatal_if(!txQueue.empty() && txQueue.back().first > tick, + "Invalid txQueue packet order in EtherLink!\n"); + txQueue.emplace_back(std::make_pair(tick, delayed_packet)); + } - packet->serialize("packet", cp); -} - - -void -LinkDelayEvent::unserialize(CheckpointIn &cp) -{ - Event::unserialize(cp); - - EtherLink *parent; - bool number; - UNSERIALIZE_OBJPTR(parent); - UNSERIALIZE_SCALAR(number); - - link = parent->link[number]; - - packet = make_shared<EthPacketData>(16384); - packet->unserialize("packet", cp); -} - - -Serializable * -LinkDelayEvent::createForUnserialize(CheckpointIn &cp, const string §ion) -{ - return new LinkDelayEvent(); + if (!txQueue.empty()) + parent->schedule(txQueueEvent, txQueue.front().first); + } else { + // We can't reliably convert in-flight packets from old + // checkpoints. In fact, gem5 hasn't been able to load these + // packets for at least two years before the format change. + warn("Old-style EtherLink serialization format detected, " + "in-flight packets may have been dropped.\n"); + } } -REGISTER_SERIALIZEABLE("LinkDelayEvent", LinkDelayEvent) - EtherLink * EtherLinkParams::create() { diff --git a/src/dev/etherlink.hh b/src/dev/etherlink.hh index 525e8250d..4bfb751b9 100644 --- a/src/dev/etherlink.hh +++ b/src/dev/etherlink.hh @@ -1,4 +1,16 @@ /* + * Copyright (c) 2015 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * * Copyright (c) 2002-2005 The Regents of The University of Michigan * All rights reserved. * @@ -35,6 +47,8 @@ #ifndef __DEV_ETHERLINK_HH__ #define __DEV_ETHERLINK_HH__ +#include <queue> + #include "base/types.hh" #include "dev/etherint.hh" #include "dev/etherobject.hh" @@ -53,25 +67,24 @@ class EtherLink : public EtherObject protected: class Interface; - friend class LinkDelayEvent; - /* - * Model for a single uni-directional link - */ + /* + * Model for a single uni-directional link + */ class Link { protected: - std::string objName; + const std::string objName; - EtherLink *parent; - int number; + EtherLink *const parent; + const int number; Interface *txint; Interface *rxint; - double ticksPerByte; - Tick linkDelay; - Tick delayVar; - EtherDump *dump; + const double ticksPerByte; + const Tick linkDelay; + const Tick delayVar; + EtherDump *const dump; protected: /* @@ -83,7 +96,18 @@ class EtherLink : public EtherObject friend void DoneEvent::process(); DoneEvent doneEvent; - friend class LinkDelayEvent; + /** + * Maintain a queue of in-flight packets. Assume that the + * delay is non-zero and constant (i.e., at most one packet + * per tick). + */ + std::deque<std::pair<Tick, EthPacketPtr>> txQueue; + + void processTxQueue(); + typedef EventWrapper<Link, &Link::processTxQueue> TxQueueEvent; + friend void TxQueueEvent::process(); + TxQueueEvent txQueueEvent; + void txComplete(EthPacketPtr packet); public: |