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44 #include "debug/PacketQueue.hh"
45 #include "mem/packet_queue.hh"
49 PacketQueue::PacketQueue(EventManager
& _em
, const std::string
& _label
)
50 : em(_em
), sendEvent(this), drainEvent(NULL
), label(_label
),
55 PacketQueue::~PacketQueue()
62 DPRINTF(PacketQueue
, "Queue %s received retry\n", name());
63 assert(waitingOnRetry
);
68 PacketQueue::checkFunctional(PacketPtr pkt
)
70 pkt
->pushLabel(label
);
72 DeferredPacketIterator i
= transmitList
.begin();
73 DeferredPacketIterator end
= transmitList
.end();
76 while (!found
&& i
!= end
) {
77 // If the buffered packet contains data, and it overlaps the
78 // current packet, then update data
79 found
= pkt
->checkFunctional(i
->pkt
);
89 PacketQueue::schedSendEvent(Tick when
)
91 // if we are waiting on a retry, do not schedule a send event, and
92 // instead rely on retry being called
94 assert(!sendEvent
.scheduled());
98 if (!sendEvent
.scheduled()) {
99 em
.schedule(&sendEvent
, when
);
100 } else if (sendEvent
.when() > when
) {
101 em
.reschedule(&sendEvent
, when
);
106 PacketQueue::schedSendTiming(PacketPtr pkt
, Tick when
, bool send_as_snoop
)
108 assert(when
> curTick());
110 // nothing on the list, or earlier than current front element,
112 if (transmitList
.empty() || when
< transmitList
.front().tick
) {
113 // note that currently we ignore a potentially outstanding retry
114 // and could in theory put a new packet at the head of the
115 // transmit list before retrying the existing packet
116 transmitList
.push_front(DeferredPacket(when
, pkt
, send_as_snoop
));
117 schedSendEvent(when
);
121 // list is non-empty and this belongs at the end
122 if (when
>= transmitList
.back().tick
) {
123 transmitList
.push_back(DeferredPacket(when
, pkt
, send_as_snoop
));
127 // this belongs in the middle somewhere, insertion sort
128 DeferredPacketIterator i
= transmitList
.begin();
129 ++i
; // already checked for insertion at front
130 while (i
!= transmitList
.end() && when
>= i
->tick
)
132 transmitList
.insert(i
, DeferredPacket(when
, pkt
, send_as_snoop
));
135 void PacketQueue::trySendTiming()
137 assert(deferredPacketReady());
139 // take the next packet off the list here, as we might return to
140 // ourselves through the sendTiming call below
141 DeferredPacket dp
= transmitList
.front();
142 transmitList
.pop_front();
144 // use the appropriate implementation of sendTiming based on the
145 // type of port associated with the queue, and whether the packet
146 // is to be sent as a snoop or not
147 waitingOnRetry
= !sendTiming(dp
.pkt
, dp
.sendAsSnoop
);
149 if (waitingOnRetry
) {
150 // put the packet back at the front of the list (packet should
151 // not have changed since it wasn't accepted)
152 assert(!sendEvent
.scheduled());
153 transmitList
.push_front(dp
);
158 PacketQueue::scheduleSend(Tick time
)
160 // the next ready time is either determined by the next deferred packet,
161 // or in the cache through the MSHR ready time
162 Tick nextReady
= std::min(deferredPacketReadyTime(), time
);
164 if (nextReady
!= MaxTick
) {
165 // if the sendTiming caused someone else to call our
166 // recvTiming we could already have an event scheduled, check
167 if (!sendEvent
.scheduled())
168 em
.schedule(&sendEvent
, std::max(nextReady
, curTick() + 1));
170 // no more to send, so if we're draining, we may be done
171 if (drainEvent
&& !sendEvent
.scheduled()) {
172 drainEvent
->process();
179 PacketQueue::sendDeferredPacket()
181 // try to send what is on the list, this will set waitingOnRetry
185 // if we succeeded and are not waiting for a retry, schedule the
187 if (!waitingOnRetry
) {
193 PacketQueue::processSendEvent()
195 assert(!waitingOnRetry
);
196 sendDeferredPacket();
200 PacketQueue::drain(Event
*de
)
202 if (transmitList
.empty() && !sendEvent
.scheduled())
208 MasterPacketQueue::MasterPacketQueue(EventManager
& _em
, MasterPort
& _masterPort
,
209 const std::string _label
)
210 : PacketQueue(_em
, _label
), masterPort(_masterPort
)
215 MasterPacketQueue::sendTiming(PacketPtr pkt
, bool send_as_snoop
)
217 // attempt to send the packet and return according to the outcome
219 return masterPort
.sendTimingReq(pkt
);
221 return masterPort
.sendTimingSnoopResp(pkt
);
224 SlavePacketQueue::SlavePacketQueue(EventManager
& _em
, SlavePort
& _slavePort
,
225 const std::string _label
)
226 : PacketQueue(_em
, _label
), slavePort(_slavePort
)
231 SlavePacketQueue::sendTiming(PacketPtr pkt
, bool send_as_snoop
)
233 // we should never have queued snoop requests
234 assert(!send_as_snoop
);
235 return slavePort
.sendTimingResp(pkt
);