diff options
Diffstat (limited to 'src/mem/simple_mem.cc')
| -rw-r--r-- | src/mem/simple_mem.cc | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/src/mem/simple_mem.cc b/src/mem/simple_mem.cc index 639ccbe31..d4dbe1946 100644 --- a/src/mem/simple_mem.cc +++ b/src/mem/simple_mem.cc @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010-2013 ARM Limited + * Copyright (c) 2010-2013, 2015 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -116,7 +116,10 @@ SimpleMemory::recvTimingReq(PacketPtr pkt) return false; } - // @todo someone should pay for this + // technically the packet only reaches us after the header delay, + // and since this is a memory controller we also need to + // deserialise the payload before performing any write operation + Tick receive_delay = pkt->headerDelay + pkt->payloadDelay; pkt->headerDelay = pkt->payloadDelay = 0; // update the release time according to the bandwidth limit, and @@ -150,10 +153,24 @@ SimpleMemory::recvTimingReq(PacketPtr pkt) // recvAtomic() should already have turned packet into // atomic response assert(pkt->isResponse()); - // to keep things simple (and in order), we put the packet at - // the end even if the latency suggests it should be sent - // before the packet(s) before it - packetQueue.emplace_back(pkt, curTick() + getLatency()); + + Tick when_to_send = curTick() + receive_delay + getLatency(); + + // typically this should be added at the end, so start the + // insertion sort with the last element, also make sure not to + // re-order in front of some existing packet with the same + // address, the latter is important as this memory effectively + // hands out exclusive copies (shared is not asserted) + auto i = packetQueue.end(); + --i; + while (i != packetQueue.begin() && when_to_send < i->tick && + i->pkt->getAddr() != pkt->getAddr()) + --i; + + // emplace inserts the element before the position pointed to by + // the iterator, so advance it one step + packetQueue.emplace(++i, pkt, when_to_send); + if (!retryResp && !dequeueEvent.scheduled()) schedule(dequeueEvent, packetQueue.back().tick); } else { |