gem5  v20.1.0.0
tport.cc
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40 
41 #include "mem/tport.hh"
42 #include "sim/sim_object.hh"
43 
44 SimpleTimingPort::SimpleTimingPort(const std::string& _name,
45  SimObject* _owner) :
46  QueuedResponsePort(_name, _owner, queueImpl), queueImpl(*_owner, *this)
47 {
48 }
49 
50 void
52 {
53  if (!respQueue.trySatisfyFunctional(pkt)) {
54  // do an atomic access and throw away the returned latency
55  recvAtomic(pkt);
56  }
57 }
58 
59 bool
61 {
62  // the SimpleTimingPort should not be used anywhere where there is
63  // a need to deal with snoop responses and their flow control
64  // requirements
65  if (pkt->cacheResponding())
66  panic("SimpleTimingPort should never see packets with the "
67  "cacheResponding flag set\n");
68 
69  bool needsResponse = pkt->needsResponse();
70  Tick latency = recvAtomic(pkt);
71  // turn packet around to go back to requestor if response expected
72  if (needsResponse) {
73  // recvAtomic() should already have turned packet into
74  // atomic response
75  assert(pkt->isResponse());
76  schedTimingResp(pkt, curTick() + latency);
77  } else {
78  // queue the packet for deletion
79  pendingDelete.reset(pkt);
80  }
81 
82  return true;
83 }
SimpleTimingPort::recvTimingReq
bool recvTimingReq(PacketPtr pkt)
Implemented using recvAtomic().
Definition: tport.cc:60
Packet::isResponse
bool isResponse() const
Definition: packet.hh:560
Packet::cacheResponding
bool cacheResponding() const
Definition: packet.hh:619
Tick
uint64_t Tick
Tick count type.
Definition: types.hh:63
QueuedResponsePort::schedTimingResp
void schedTimingResp(PacketPtr pkt, Tick when)
Schedule the sending of a timing response.
Definition: qport.hh:90
sim_object.hh
Packet::needsResponse
bool needsResponse() const
Definition: packet.hh:570
QueuedResponsePort
A queued port is a port that has an infinite queue for outgoing packets and thus decouples the module...
Definition: qport.hh:58
SimpleTimingPort::recvFunctional
void recvFunctional(PacketPtr pkt)
Implemented using recvAtomic().
Definition: tport.cc:51
SimpleTimingPort::SimpleTimingPort
SimpleTimingPort(const std::string &name, SimObject *owner)
Create a new SimpleTimingPort that relies on a packet queue to hold responses, and implements recvTim...
Definition: tport.cc:44
QueuedResponsePort::respQueue
RespPacketQueue & respQueue
Packet queue used to store outgoing responses.
Definition: qport.hh:64
PacketQueue::trySatisfyFunctional
bool trySatisfyFunctional(PacketPtr pkt)
Check the list of buffered packets against the supplied functional request.
Definition: packet_queue.cc:84
tport.hh
SimpleTimingPort::recvAtomic
virtual Tick recvAtomic(PacketPtr pkt)=0
Receive an atomic request packet from the peer.
Packet
A Packet is used to encapsulate a transfer between two objects in the memory system (e....
Definition: packet.hh:257
SimpleTimingPort::pendingDelete
std::unique_ptr< Packet > pendingDelete
Upstream caches need this packet until true is returned, so hold it for deletion until a subsequent c...
Definition: tport.hh:86
panic
#define panic(...)
This implements a cprintf based panic() function.
Definition: logging.hh:171
curTick
Tick curTick()
The current simulated tick.
Definition: core.hh:45
SimObject
Abstract superclass for simulation objects.
Definition: sim_object.hh:92

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