diff options
Diffstat (limited to 'src/mem/packet_queue.hh')
| -rw-r--r-- | src/mem/packet_queue.hh | 160 |
1 files changed, 87 insertions, 73 deletions
diff --git a/src/mem/packet_queue.hh b/src/mem/packet_queue.hh index 3ed3fae28..164ff6345 100644 --- a/src/mem/packet_queue.hh +++ b/src/mem/packet_queue.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2012 ARM Limited + * Copyright (c) 2012,2015 ARM Limited * All rights reserved. * * The license below extends only to copyright in the software and shall @@ -49,8 +49,7 @@ * Declaration of a simple PacketQueue that is associated with * a port on which it attempts to send packets according to the time * stamp given to them at insertion. The packet queue is responsible - * for the flow control of the port, but relies on the module - * notifying the queue when a transfer ends. + * for the flow control of the port. */ #include <list> @@ -71,28 +70,23 @@ class PacketQueue : public Drainable public: Tick tick; ///< The tick when the packet is ready to transmit PacketPtr pkt; ///< Pointer to the packet to transmit - bool sendAsSnoop; ///< Should it be sent as a snoop or not - DeferredPacket(Tick t, PacketPtr p, bool send_as_snoop) - : tick(t), pkt(p), sendAsSnoop(send_as_snoop) + DeferredPacket(Tick t, PacketPtr p) + : tick(t), pkt(p) {} }; typedef std::list<DeferredPacket> DeferredPacketList; - /** A list of outgoing timing response packets that haven't been - * serviced yet. */ + /** A list of outgoing packets. */ DeferredPacketList transmitList; /** The manager which is used for the event queue */ EventManager& em; - /** This function attempts to send deferred packets. Scheduled to - * be called in the future via SendEvent. */ + /** Used to schedule sending of deferred packets. */ void processSendEvent(); - /** - * Event used to call processSendEvent. - **/ + /** Event used to call processSendEvent. */ EventWrapper<PacketQueue, &PacketQueue::processSendEvent> sendEvent; /** If we need to drain, keep the drain manager around until we're done @@ -104,55 +98,28 @@ class PacketQueue : public Drainable /** Label to use for print request packets label stack. */ const std::string label; - /** Remember whether we're awaiting a retry from the bus. */ + /** Remember whether we're awaiting a retry. */ bool waitingOnRetry; /** Check whether we have a packet ready to go on the transmit list. */ bool deferredPacketReady() const { return !transmitList.empty() && transmitList.front().tick <= curTick(); } - Tick deferredPacketReadyTime() const - { return transmitList.empty() ? MaxTick : transmitList.front().tick; } - /** - * Attempt to send the packet at the head of the transmit - * list. Caller must guarantee that the list is non-empty and that - * the head packet is scheduled for curTick() (or earlier). Note - * that a subclass of the PacketQueue can override this method and - * thus change the behaviour (as done by the cache). + * Attempt to send a packet. Note that a subclass of the + * PacketQueue can override this method and thus change the + * behaviour (as done by the cache for the request queue). The + * default implementation sends the head of the transmit list. The + * caller must guarantee that the list is non-empty and that the + * head packet is scheduled for curTick() (or earlier). */ virtual void sendDeferredPacket(); /** - * Attempt to send the packet at the front of the transmit list, - * and set waitingOnRetry accordingly. The packet is temporarily - * taken off the list, but put back at the front if not - * successfully sent. + * Send a packet using the appropriate method for the specific + * subclass (reuest, response or snoop response). */ - void trySendTiming(); - - /** - * - */ - virtual bool sendTiming(PacketPtr pkt, bool send_as_snoop) = 0; - - /** - * Based on the transmit list, or the provided time, schedule a - * send event if there are packets to send. If we are idle and - * asked to drain then do so. - * - * @param time an alternative time for the next send event - */ - void scheduleSend(Tick time = MaxTick); - - /** - * Simple ports are generally used as slave ports (i.e. the - * respond to requests) and thus do not expect to receive any - * range changes (as the neighbouring port has a master role and - * do not have any address ranges. A subclass can override the - * default behaviuor if needed. - */ - virtual void recvRangeChange() { } + virtual bool sendTiming(PacketPtr pkt) = 0; /** * Create a packet queue, linked to an event manager, and a label @@ -177,40 +144,56 @@ class PacketQueue : public Drainable */ virtual const std::string name() const = 0; + /** + * Get the size of the queue. + */ + size_t size() const { return transmitList.size(); } + + /** + * Get the next packet ready time. + */ + Tick deferredPacketReadyTime() const + { return transmitList.empty() ? MaxTick : transmitList.front().tick; } + + /** + * Check if a packets address exists in the queue. + */ + bool hasAddr(Addr addr) const; + /** Check the list of buffered packets against the supplied * functional request. */ bool checkFunctional(PacketPtr pkt); /** - * Schedule a send even if not already waiting for a retry. If the - * requested time is before an already scheduled send event it - * will be rescheduled. + * Schedule a send event if we are not already waiting for a + * retry. If the requested time is before an already scheduled + * send event, the event will be rescheduled. If MaxTick is + * passed, no event is scheduled. Instead, if we are idle and + * asked to drain then check and signal drained. * - * @param when + * @param when time to schedule an event */ void schedSendEvent(Tick when); /** - * Add a packet to the transmit list, and ensure that a - * processSendEvent is called in the future. + * Add a packet to the transmit list, and schedule a send event. * * @param pkt Packet to send * @param when Absolute time (in ticks) to send packet - * @param send_as_snoop Send the packet as a snoop or not */ - void schedSendTiming(PacketPtr pkt, Tick when, bool send_as_snoop = false); + void schedSendTiming(PacketPtr pkt, Tick when); /** - * Used by a port to notify the queue that a retry was received - * and that the queue can proceed and retry sending the packet - * that caused the wait. + * Retry sending a packet from the queue. Note that this is not + * necessarily the same packet if something has been added with an + * earlier time stamp. */ void retry(); unsigned int drain(DrainManager *dm); }; -class MasterPacketQueue : public PacketQueue +class ReqPacketQueue : public PacketQueue { protected: @@ -220,7 +203,7 @@ class MasterPacketQueue : public PacketQueue public: /** - * Create a master packet queue, linked to an event manager, a + * Create a request packet queue, linked to an event manager, a * master port, and a label that will be used for functional print * request packets. * @@ -228,18 +211,49 @@ class MasterPacketQueue : public PacketQueue * @param _masterPort Master port used to send the packets * @param _label Label to push on the label stack for print request packets */ - MasterPacketQueue(EventManager& _em, MasterPort& _masterPort, - const std::string _label = "MasterPacketQueue"); + ReqPacketQueue(EventManager& _em, MasterPort& _masterPort, + const std::string _label = "ReqPacketQueue"); + + virtual ~ReqPacketQueue() { } + + const std::string name() const + { return masterPort.name() + "-" + label; } + + bool sendTiming(PacketPtr pkt); + +}; + +class SnoopRespPacketQueue : public PacketQueue +{ + + protected: + + MasterPort& masterPort; + + public: + + /** + * Create a snoop response packet queue, linked to an event + * manager, a master port, and a label that will be used for + * functional print request packets. + * + * @param _em Event manager used for scheduling this queue + * @param _masterPort Master port used to send the packets + * @param _label Label to push on the label stack for print request packets + */ + SnoopRespPacketQueue(EventManager& _em, MasterPort& _masterPort, + const std::string _label = "SnoopRespPacketQueue"); - virtual ~MasterPacketQueue() { } + virtual ~SnoopRespPacketQueue() { } const std::string name() const { return masterPort.name() + "-" + label; } - bool sendTiming(PacketPtr pkt, bool send_as_snoop); + bool sendTiming(PacketPtr pkt); + }; -class SlavePacketQueue : public PacketQueue +class RespPacketQueue : public PacketQueue { protected: @@ -249,7 +263,7 @@ class SlavePacketQueue : public PacketQueue public: /** - * Create a slave packet queue, linked to an event manager, a + * Create a response packet queue, linked to an event manager, a * slave port, and a label that will be used for functional print * request packets. * @@ -257,15 +271,15 @@ class SlavePacketQueue : public PacketQueue * @param _slavePort Slave port used to send the packets * @param _label Label to push on the label stack for print request packets */ - SlavePacketQueue(EventManager& _em, SlavePort& _slavePort, - const std::string _label = "SlavePacketQueue"); + RespPacketQueue(EventManager& _em, SlavePort& _slavePort, + const std::string _label = "RespPacketQueue"); - virtual ~SlavePacketQueue() { } + virtual ~RespPacketQueue() { } const std::string name() const { return slavePort.name() + "-" + label; } - bool sendTiming(PacketPtr pkt, bool send_as_snoop); + bool sendTiming(PacketPtr pkt); }; |