diff options
| -rw-r--r-- | src/mem/packet_queue.cc | 53 | ||||
| -rw-r--r-- | src/mem/packet_queue.hh | 3 |
2 files changed, 16 insertions, 40 deletions
diff --git a/src/mem/packet_queue.cc b/src/mem/packet_queue.cc index e7ad1cc47..a9fe29e86 100644 --- a/src/mem/packet_queue.cc +++ b/src/mem/packet_queue.cc @@ -119,29 +119,8 @@ PacketQueue::schedSendTiming(PacketPtr pkt, Tick when, bool force_order) name()); } - // if requested, force the timing to be in-order by changing the when - // parameter - if (force_order && !transmitList.empty()) { - Tick back = transmitList.back().tick; - - // fudge timing if required; relies on the code below to do the right - // thing (push_back) with the updated time-stamp - if (when < back) { - DPRINTF(PacketQueue, "%s force_order shifted packet %s address "\ - "%x from %lu to %lu\n", __func__, pkt->cmdString(), - pkt->getAddr(), when, back); - when = back; - } - } - - // nothing on the list, or earlier than current front element, - // schedule an event - if (transmitList.empty() || when < transmitList.front().tick) { - // force_order-ed in here only when list is empty - assert(!force_order || transmitList.empty()); - // note that currently we ignore a potentially outstanding retry - // and could in theory put a new packet at the head of the - // transmit list before retrying the existing packet + // nothing on the list + if (transmitList.empty()) { transmitList.emplace_front(when, pkt); schedSendEvent(when); return; @@ -155,21 +134,19 @@ PacketQueue::schedSendTiming(PacketPtr pkt, Tick when, bool force_order) // ourselves again before we had a chance to update waitingOnRetry // assert(waitingOnRetry || sendEvent.scheduled()); - // list is non-empty and this belongs at the end - if (when >= transmitList.back().tick) { - transmitList.emplace_back(when, pkt); - return; - } - - // forced orders never need insertion in the middle - assert(!force_order); - - // this belongs in the middle somewhere, insertion sort - auto i = transmitList.begin(); - ++i; // already checked for insertion at front - while (i != transmitList.end() && when >= i->tick) - ++i; - transmitList.emplace(i, when, pkt); + // this belongs in the middle somewhere, so search from the end to + // order by tick; however, if force_order is set, also make sure + // not to re-order in front of some existing packet with the same + // address + auto i = transmitList.end(); + --i; + while (i != transmitList.begin() && when < i->tick && + !(force_order && i->pkt->getAddr() == pkt->getAddr())) + --i; + + // emplace inserts the element before the position pointed to by + // the iterator, so advance it one step + transmitList.emplace(++i, when, pkt); } void diff --git a/src/mem/packet_queue.hh b/src/mem/packet_queue.hh index e9cf34bb0..866a4477a 100644 --- a/src/mem/packet_queue.hh +++ b/src/mem/packet_queue.hh @@ -176,8 +176,7 @@ class PacketQueue : public Drainable * * @param pkt Packet to send * @param when Absolute time (in ticks) to send packet - * @param force_order Do not reorder packets despite timing, but keep them - * in insertion order. + * @param force_order Force insertion order for packets with same address */ void schedSendTiming(PacketPtr pkt, Tick when, bool force_order = false); |