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44 #include "debug/Drain.hh"
45 #include "debug/PacketQueue.hh"
46 #include "mem/packet_queue.hh"
50 PacketQueue::PacketQueue(EventManager
& _em
, const std::string
& _label
)
51 : em(_em
), sendEvent(this), drainManager(NULL
), label(_label
),
56 PacketQueue::~PacketQueue()
63 DPRINTF(PacketQueue
, "Queue %s received retry\n", name());
64 assert(waitingOnRetry
);
69 PacketQueue::checkFunctional(PacketPtr pkt
)
71 pkt
->pushLabel(label
);
73 DeferredPacketIterator i
= transmitList
.begin();
74 DeferredPacketIterator end
= transmitList
.end();
77 while (!found
&& i
!= end
) {
78 // If the buffered packet contains data, and it overlaps the
79 // current packet, then update data
80 found
= pkt
->checkFunctional(i
->pkt
);
90 PacketQueue::schedSendEvent(Tick when
)
92 // if we are waiting on a retry, do not schedule a send event, and
93 // instead rely on retry being called
95 assert(!sendEvent
.scheduled());
99 if (!sendEvent
.scheduled()) {
100 em
.schedule(&sendEvent
, when
);
101 } else if (sendEvent
.when() > when
) {
102 em
.reschedule(&sendEvent
, when
);
107 PacketQueue::schedSendTiming(PacketPtr pkt
, Tick when
, bool send_as_snoop
)
109 // we can still send a packet before the end of this tick
110 assert(when
>= curTick());
112 // express snoops should never be queued
113 assert(!pkt
->isExpressSnoop());
115 // nothing on the list, or earlier than current front element,
117 if (transmitList
.empty() || when
< transmitList
.front().tick
) {
118 // note that currently we ignore a potentially outstanding retry
119 // and could in theory put a new packet at the head of the
120 // transmit list before retrying the existing packet
121 transmitList
.push_front(DeferredPacket(when
, pkt
, send_as_snoop
));
122 schedSendEvent(when
);
126 // list is non-empty and this belongs at the end
127 if (when
>= transmitList
.back().tick
) {
128 transmitList
.push_back(DeferredPacket(when
, pkt
, send_as_snoop
));
132 // this belongs in the middle somewhere, insertion sort
133 DeferredPacketIterator i
= transmitList
.begin();
134 ++i
; // already checked for insertion at front
135 while (i
!= transmitList
.end() && when
>= i
->tick
)
137 transmitList
.insert(i
, DeferredPacket(when
, pkt
, send_as_snoop
));
140 void PacketQueue::trySendTiming()
142 assert(deferredPacketReady());
144 // take the next packet off the list here, as we might return to
145 // ourselves through the sendTiming call below
146 DeferredPacket dp
= transmitList
.front();
147 transmitList
.pop_front();
149 // use the appropriate implementation of sendTiming based on the
150 // type of port associated with the queue, and whether the packet
151 // is to be sent as a snoop or not
152 waitingOnRetry
= !sendTiming(dp
.pkt
, dp
.sendAsSnoop
);
154 if (waitingOnRetry
) {
155 // put the packet back at the front of the list (packet should
156 // not have changed since it wasn't accepted)
157 assert(!sendEvent
.scheduled());
158 transmitList
.push_front(dp
);
163 PacketQueue::scheduleSend(Tick time
)
165 // the next ready time is either determined by the next deferred packet,
166 // or in the cache through the MSHR ready time
167 Tick nextReady
= std::min(deferredPacketReadyTime(), time
);
169 if (nextReady
!= MaxTick
) {
170 // if the sendTiming caused someone else to call our
171 // recvTiming we could already have an event scheduled, check
172 if (!sendEvent
.scheduled())
173 em
.schedule(&sendEvent
, std::max(nextReady
, curTick() + 1));
175 // no more to send, so if we're draining, we may be done
176 if (drainManager
&& transmitList
.empty() && !sendEvent
.scheduled()) {
177 DPRINTF(Drain
, "PacketQueue done draining,"
178 "processing drain event\n");
179 drainManager
->signalDrainDone();
186 PacketQueue::sendDeferredPacket()
188 // try to send what is on the list, this will set waitingOnRetry
192 // if we succeeded and are not waiting for a retry, schedule the
194 if (!waitingOnRetry
) {
200 PacketQueue::processSendEvent()
202 assert(!waitingOnRetry
);
203 sendDeferredPacket();
207 PacketQueue::drain(DrainManager
*dm
)
209 if (transmitList
.empty() && !sendEvent
.scheduled())
211 DPRINTF(Drain
, "PacketQueue not drained\n");
216 MasterPacketQueue::MasterPacketQueue(EventManager
& _em
, MasterPort
& _masterPort
,
217 const std::string _label
)
218 : PacketQueue(_em
, _label
), masterPort(_masterPort
)
223 MasterPacketQueue::sendTiming(PacketPtr pkt
, bool send_as_snoop
)
225 // attempt to send the packet and return according to the outcome
227 return masterPort
.sendTimingReq(pkt
);
229 return masterPort
.sendTimingSnoopResp(pkt
);
232 SlavePacketQueue::SlavePacketQueue(EventManager
& _em
, SlavePort
& _slavePort
,
233 const std::string _label
)
234 : PacketQueue(_em
, _label
), slavePort(_slavePort
)
239 SlavePacketQueue::sendTiming(PacketPtr pkt
, bool send_as_snoop
)
241 // we should never have queued snoop requests
242 assert(!send_as_snoop
);
243 return slavePort
.sendTimingResp(pkt
);