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2013-07-18mem: Set the cache line size on a system levelAndreas Hansson
This patch removes the notion of a peer block size and instead sets the cache line size on the system level. Previously the size was set per cache, and communicated through the interconnect. There were plenty checks to ensure that everyone had the same size specified, and these checks are now removed. Another benefit that is not yet harnessed is that the cache line size is now known at construction time, rather than after the port binding. Hence, the block size can be locally stored and does not have to be queried every time it is used. A follow-on patch updates the configuration scripts accordingly.
2013-06-27mem: Tidy up the bridge with const and additional checksAndreas Hansson
This patch does a bit of tidying up in the bridge code, adding const where appropriate and also removing redundant checks and adding a few new ones. There are no changes to the behaviour of any regressions.
2013-04-22sim: separate nextCycle() and clockEdge() in clockedObjectsDam Sunwoo
Previously, nextCycle() could return the *current* cycle if the current tick was already aligned with the clock edge. This behavior is not only confusing (not quite what the function name implies), but also caused problems in the drainResume() function. When exiting/re-entering the sim loop (e.g., to take checkpoints), the CPUs will drain and resume. Due to the previous behavior of nextCycle(), the CPU tick events were being rescheduled in the same ticks that were already processed before draining. This caused divergence from runs that did not exit/re-entered the sim loop. (Initially a cycle difference, but a significant impact later on.) This patch separates out the two behaviors (nextCycle() and clockEdge()), uses nextCycle() in drainResume, and uses clockEdge() everywhere else. Nothing (other than name) should change except for the drainResume timing.
2013-02-19mem: Enforce strict use of busFirst- and busLastWordTimeAndreas Hansson
This patch adds a check to ensure that the delay incurred by the bus is not simply disregarded, but accounted for by someone. At this point, all the modules do is to zero it out, and no additional time is spent. This highlights where the bus timing is simply dropped instead of being paid for. As a follow up, the locations identified in this patch should add this additional time to the packets in one way or another. For now it simply acts as a sanity check and highlights where the delay is simply ignored. Since no time is added, all regressions remain the same.
2013-02-19mem: Add predecessor to SenderState base classAndreas Hansson
This patch adds a predecessor field to the SenderState base class to make the process of linking them up more uniform, and enable a traversal of the stack without knowing the specific type of the subclasses. There are a number of simplifications done as part of changing the SenderState, particularly in the RubyTest.
2012-10-15Port: Add protocol-agnostic ports in the port hierarchyAndreas Hansson
This patch adds an additional level of ports in the inheritance hierarchy, separating out the protocol-specific and protocl-agnostic parts. All the functionality related to the binding of ports is now confined to use BaseMaster/BaseSlavePorts, and all the protocol-specific parts stay in the Master/SlavePort. In the future it will be possible to add other protocol-specific implementations. The functions used in the binding of ports, i.e. getMaster/SlavePort now use the base classes, and the index parameter is updated to use the PortID typedef with the symbolic InvalidPortID as the default.
2012-09-19AddrRange: Transition from Range<T> to AddrRangeAndreas Hansson
This patch takes the final plunge and transitions from the templated Range class to the more specific AddrRange. In doing so it changes the obvious Range<Addr> to AddrRange, and also bumps the range_map to be AddrRangeMap. In addition to the obvious changes, including the removal of redundant includes, this patch also does some house keeping in preparing for the introduction of address interleaving support in the ranges. The Range class is also stripped of all the functionality that is never used. --HG-- rename : src/base/range.hh => src/base/addr_range.hh rename : src/base/range_map.hh => src/base/addr_range_map.hh
2012-08-28Clock: Add a Cycles wrapper class and use where applicableAndreas Hansson
This patch addresses the comments and feedback on the preceding patch that reworks the clocks and now more clearly shows where cycles (relative cycle counts) are used to express time. Instead of bumping the existing patch I chose to make this a separate patch, merely to try and focus the discussion around a smaller set of changes. The two patches will be pushed together though. This changes done as part of this patch are mostly following directly from the introduction of the wrapper class, and change enough code to make things compile and run again. There are definitely more places where int/uint/Tick is still used to represent cycles, and it will take some time to chase them all down. Similarly, a lot of parameters should be changed from Param.Tick and Param.Unsigned to Param.Cycles. In addition, the use of curTick is questionable as there should not be an absolute cycle. Potential solutions can be built on top of this patch. There is a similar situation in the o3 CPU where lastRunningCycle is currently counting in Cycles, and is still an absolute time. More discussion to be had in other words. An additional change that would be appropriate in the future is to perform a similar wrapping of Tick and probably also introduce a Ticks class along with suitable operators for all these classes.
2012-08-22Bridge: Remove NACKs in the bridge and unify with packet queueAndreas Hansson
This patch removes the NACKing in the bridge, as the split request/response busses now ensure that protocol deadlocks do not occur, i.e. the message-dependency chain is broken by always allowing responses to make progress without being stalled by requests. The NACKs had limited support in the system with most components ignoring their use (with a suitable call to panic), and as the NACKs are no longer needed to avoid protocol deadlocks, the cleanest way is to simply remove them. The bridge is the starting point as this is the only place where the NACKs are created. A follow-up patch will remove the code that deals with NACKs in the endpoints, e.g. the X86 table walker and DMA port. Ultimately the type of packet can be complete removed (until someone sees a need for modelling more complex protocols, which can now be done in parts of the system since the port and interface is split). As a consequence of the NACK removal, the bridge now has to send a retry to a master if the request or response queue was full on the first attempt. This change also makes the bridge ports very similar to QueuedPorts, and a later patch will change the bridge to use these. A first step in this direction is taken by aligning the name of the member functions, as done by this patch. A bit of tidying up has also been done as part of the simplifications. Surprisingly, this patch has no impact on any of the regressions. Hence, there was never any NACKs issued. In a follow-up patch I would suggest changing the size of the bridge buffers set in FSConfig.py to also test the situation where the bridge fills up.
2012-07-09Port: Align port names in C++ and PythonAndreas Hansson
This patch is a first step to align the port names used in the Python world and the C++ world. Ultimately it serves to make the use of config.json together with output from the simulation easier, including post-processing of statistics. Most notably, the CPU, cache, and bus is addressed in this patch, and there might be other ports that should be updated accordingly. The dash name separator has also been replaced with a "." which is what is used to concatenate the names in python, and a separation is made between the master and slave port in the bus.
2012-07-09Port: Make getAddrRanges constAndreas Hansson
This patch makes getAddrRanges const throughout the code base. There is no reason why it should not be, and making it const prevents adding any unintentional side-effects.
2012-05-30Bridge: Split deferred request, response and sender stateAndreas Hansson
This patch splits the PacketBuffer class into a RequestState and a DeferredRequest and DeferredResponse. Only the requests need a SenderState, and the deferred requests and responses only need an associated point in time for the request and the response queue. Besides the cleaning up, the goal is to simplify the transition to a new port handshake, and with these changes, the two packet queues are starting to look very similar to the generic packet queue, but currently they do a few unique things relating to the NACK and counting of requests/responses that the packet queue cannot be conveniently used. This will be addressed in a later patch.
2012-05-01MEM: Separate requests and responses for timing accessesAndreas Hansson
This patch moves send/recvTiming and send/recvTimingSnoop from the Port base class to the MasterPort and SlavePort, and also splits them into separate member functions for requests and responses: send/recvTimingReq, send/recvTimingResp, and send/recvTimingSnoopReq, send/recvTimingSnoopResp. A master port sends requests and receives responses, and also receives snoop requests and sends snoop responses. A slave port has the reciprocal behaviour as it receives requests and sends responses, and sends snoop requests and receives snoop responses. For all MemObjects that have only master ports or slave ports (but not both), e.g. a CPU, or a PIO device, this patch merely adds more clarity to what kind of access is taking place. For example, a CPU port used to call sendTiming, and will now call sendTimingReq. Similarly, a response previously came back through recvTiming, which is now recvTimingResp. For the modules that have both master and slave ports, e.g. the bus, the behaviour was previously relying on branches based on pkt->isRequest(), and this is now replaced with a direct call to the apprioriate member function depending on the type of access. Please note that send/recvRetry is still shared by all the timing accessors and remains in the Port base class for now (to maintain the current bus functionality and avoid changing the statistics of all regressions). The packet queue is split into a MasterPort and SlavePort version to facilitate the use of the new timing accessors. All uses of the PacketQueue are updated accordingly. With this patch, the type of packet (request or response) is now well defined for each type of access, and asserts on pkt->isRequest() and pkt->isResponse() are now moved to the appropriate send member functions. It is also worth noting that sendTimingSnoopReq no longer returns a boolean, as the semantics do not alow snoop requests to be rejected or stalled. All these assumptions are now excplicitly part of the port interface itself.
2012-04-14MEM: Remove the Broadcast destination from the packetAndreas Hansson
This patch simplifies the packet by removing the broadcast flag and instead more firmly relying on (and enforcing) the semantics of transactions in the classic memory system, i.e. request packets are routed from a master to a slave based on the address, and when they are created they have neither a valid source, nor destination. On their way to the slave, the request packet is updated with a source field for all modules that multiplex packets from multiple master (e.g. a bus). When a request packet is turned into a response packet (at the final slave), it moves the potentially populated source field to the destination field, and the response packet is routed through any multiplexing components back to the master based on the destination field. Modules that connect multiplexing components, such as caches and bridges store any existing source and destination field in the sender state as a stack (just as before). The packet constructor is simplified in that there is no longer a need to pass the Packet::Broadcast as the destination (this was always the case for the classic memory system). In the case of Ruby, rather than using the parameter to the constructor we now rely on setDest, as there is already another three-argument constructor in the packet class. In many places where the packet information was printed as part of DPRINTFs, request packets would be printed with a numeric "dest" that would always be -1 (Broadcast) and that field is now removed from the printing.
2012-04-14MEM: Separate snoops and normal memory requests/responsesAndreas Hansson
This patch introduces port access methods that separates snoop request/responses from normal memory request/responses. The differentiation is made for functional, atomic and timing accesses and builds on the introduction of master and slave ports. Before the introduction of this patch, the packets belonging to the different phases of the protocol (request -> [forwarded snoop request -> snoop response]* -> response) all use the same port access functions, even though the snoop packets flow in the opposite direction to the normal packet. That is, a coherent master sends normal request and receives responses, but receives snoop requests and sends snoop responses (vice versa for the slave). These two distinct phases now use different access functions, as described below. Starting with the functional access, a master sends a request to a slave through sendFunctional, and the request packet is turned into a response before the call returns. In a system without cache coherence, this is all that is needed from the functional interface. For the cache-coherent scenario, a slave also sends snoop requests to coherent masters through sendFunctionalSnoop, with responses returned within the same packet pointer. This is currently used by the bus and caches, and the LSQ of the O3 CPU. The send/recvFunctional and send/recvFunctionalSnoop are moved from the Port super class to the appropriate subclass. Atomic accesses follow the same flow as functional accesses, with request being sent from master to slave through sendAtomic. In the case of cache-coherent ports, a slave can send snoop requests to a master through sendAtomicSnoop. Just as for the functional access methods, the atomic send and receive member functions are moved to the appropriate subclasses. The timing access methods are different from the functional and atomic in that requests and responses are separated in time and send/recvTiming are used for both directions. Hence, a master uses sendTiming to send a request to a slave, and a slave uses sendTiming to send a response back to a master, at a later point in time. Snoop requests and responses travel in the opposite direction, similar to what happens in functional and atomic accesses. With the introduction of this patch, it is possible to determine the direction of packets in the bus, and no longer necessary to look for both a master and a slave port with the requested port id. In contrast to the normal recvFunctional, recvAtomic and recvTiming that are pure virtual functions, the recvFunctionalSnoop, recvAtomicSnoop and recvTimingSnoop have a default implementation that calls panic. This is to allow non-coherent master and slave ports to not implement these functions.
2012-03-30MEM: Introduce the master/slave port sub-classes in C++William Wang
This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
2012-02-24MEM: Move port creation to the memory object(s) constructionAndreas Hansson
This patch moves all port creation from the getPort method to be consistently done in the MemObject's constructor. This is possible thanks to the Swig interface passing the length of the vector ports. Previously there was a mix of: 1) creating the ports as members (at object construction time) and using getPort for the name resolution, or 2) dynamically creating the ports in the getPort call. This is now uniform. Furthermore, objects that would not be complete without a port have these ports as members rather than having pointers to dynamically allocated ports. This patch also enables an elaboration-time enumeration of all the ports in the system which can be used to determine the masterId.
2012-01-17MEM: Make the bus bridge unidirectional and fixed address rangeAndreas Hansson
This patch makes the bus bridge uni-directional and specialises the bus ports to be a master port and a slave port. This greatly simplifies the assumptions on both sides as either port only has to deal with requests or responses. The following patches introduce the notion of master and slave ports, and would not be possible without this split of responsibilities. In making the bridge unidirectional, the address range mechanism of the bridge is also changed. For the cases where communication is taking place both ways, an additional bridge is needed. This causes issues with the existing mechanism, as the busses cannot determine when to stop iterating the address updates from the two bridges. To avoid this issue, and also greatly simplify the specification, the bridge now has a fixed set of address ranges, specified at creation time.
2012-01-17MEM: Separate queries for snooping and address rangesAndreas Hansson
This patch simplifies the address-range determination mechanism and also unifies the naming across ports and devices. It further splits the queries for determining if a port is snooping and what address ranges it responds to (aiming towards a separation of cache-maintenance ports and pure memory-mapped ports). Default behaviours are such that most ports do not have to define isSnooping, and master ports need not implement getAddrRanges.
2012-01-17MEM: Remove the notion of the default portAndreas Hansson
This patch removes the default port and instead relies on the peer being set to NULL initially. The binding check (i.e. is a port connected or not) will eventually be moved to the init function of the modules.
2012-01-17MEM: Simplify ports by removing EventManagerAndreas Hansson
This patch removes the inheritance of EventManager from the ports and moves all responsibility for event queues to the owner. Eventually the event manager should be the interface block, which could either be the structural owner or a subblock like a LSQ in the O3 CPU for example.
2011-04-15trace: reimplement the DTRACE function so it doesn't use a vectorNathan Binkert
At the same time, rename the trace flags to debug flags since they have broader usage than simply tracing. This means that --trace-flags is now --debug-flags and --trace-help is now --debug-help
2011-01-07Replace curTick global variable with accessor functions.Steve Reinhardt
This step makes it easy to replace the accessor functions (which still access a global variable) with ones that access per-thread curTick values.
2010-09-09mem: fix functional accesses to deal with coherence changeSteve Reinhardt
We can't just obliviously return the first valid cache block we find any more... see comments for details.
2009-11-18ruby: Added more info to bridge error messageBrad Beckmann
2008-10-09eventq: convert all usage of events to use the new API.Nathan Binkert
For now, there is still a single global event queue, but this is necessary for making the steps towards a parallelized m5.
2008-09-26When nesting if statements, use braces to avoid ambiguous else clauses.Nathan Binkert
2008-06-28Backed out changeset 94a7bb476fca: caused memory leak.Steve Reinhardt
2008-06-21Generate more useful error messages for unconnected ports.Steve Reinhardt
Force all non-default ports to provide a name and an owner in the constructor.
2008-06-15port: Clean up default port setup and port switchover code.Nathan Binkert
2008-01-02Add functional PrintReq command for memory-system debugging.Steve Reinhardt
--HG-- extra : convert_revision : 73b753e57c355b7e6873f047ddc8cb371c3136b7
2007-11-28Make ports that aren't connected to anything fail more gracefully.Gabe Black
--HG-- extra : convert_revision : 3803b28fb2fdfd729f01f1a44df2ae02ef83a2fc
2007-08-30params: Deprecate old-style constructors; update most SimObject constructors.Miles Kaufmann
SimObjects not yet updated: - Process and subclasses - BaseCPU and subclasses The SimObject(const std::string &name) constructor was removed. Subclasses that still rely on that behavior must call the parent initializer as : SimObject(makeParams(name)) --HG-- extra : convert_revision : d6faddde76e7c3361ebdbd0a7b372a40941c12ed
2007-08-26Merge with headGabe Black
--HG-- extra : convert_revision : cc73b9aaf73e9dacf52f3350fa591e67ca4ccee6
2007-08-10DMA: Add IOCache and fix bus bridge to optionally only send requests oneAli Saidi
way so a cache can handle partial block requests for i/o devices. --HG-- extra : convert_revision : a68b5ae826731bc87ed93eb7ef326a2393053964
2007-07-26Merge python and x86 changes with cache branchNathan Binkert
--HG-- extra : convert_revision : e06a950964286604274fba81dcca362d75847233
2007-07-23Major changes to how SimObjects are created and initialized. Almost allNathan Binkert
creation and initialization now happens in python. Parameter objects are generated and initialized by python. The .ini file is now solely for debugging purposes and is not used in construction of the objects in any way. --HG-- extra : convert_revision : 7e722873e417cb3d696f2e34c35ff488b7bff4ed
2007-07-14Merge of DPRINTF fixes from head.Steve Reinhardt
--HG-- extra : convert_revision : f99a33b2df6a6c5592856d17d00e73ee83267442
2007-07-14Fix & tweak DPRINTFs for tracediff w/new cache code.Steve Reinhardt
Note that we should *not* print pointer values in DPRINTFs as these needlessly clutter tracediff output. --HG-- extra : convert_revision : 25a448f1b3ac8d453a717a104ad6dc0112fb30bb
2007-06-30Don't propagate snoops across bridges. Wouldn't work anyway.Steve Reinhardt
--HG-- extra : convert_revision : af29fc7d0c134f5e89dd2e814c819151350fcb38
2007-06-30Get rid of Packet result field. Error responses areSteve Reinhardt
now encoded in cmd field. --HG-- extra : convert_revision : d67819b7e3ee4b9a5bf08541104de0a89485e90b
2007-06-17More major reorg of cache. Seems to work for atomic mode now,Steve Reinhardt
timing mode still broken. configs/example/memtest.py: Revamp options. src/cpu/memtest/memtest.cc: No need for memory initialization. No need to make atomic response... memory system should do that now. src/cpu/memtest/memtest.hh: MemTest really doesn't want to snoop. src/mem/bridge.cc: checkFunctional() cleanup. src/mem/bus.cc: src/mem/bus.hh: src/mem/cache/base_cache.cc: src/mem/cache/base_cache.hh: src/mem/cache/cache.cc: src/mem/cache/cache.hh: src/mem/cache/cache_blk.hh: src/mem/cache/cache_builder.cc: src/mem/cache/cache_impl.hh: src/mem/cache/coherence/coherence_protocol.cc: src/mem/cache/coherence/coherence_protocol.hh: src/mem/cache/coherence/simple_coherence.hh: src/mem/cache/miss/SConscript: src/mem/cache/miss/mshr.cc: src/mem/cache/miss/mshr.hh: src/mem/cache/miss/mshr_queue.cc: src/mem/cache/miss/mshr_queue.hh: src/mem/cache/prefetch/base_prefetcher.cc: src/mem/cache/tags/fa_lru.cc: src/mem/cache/tags/fa_lru.hh: src/mem/cache/tags/iic.cc: src/mem/cache/tags/iic.hh: src/mem/cache/tags/lru.cc: src/mem/cache/tags/lru.hh: src/mem/cache/tags/split.cc: src/mem/cache/tags/split.hh: src/mem/cache/tags/split_lifo.cc: src/mem/cache/tags/split_lifo.hh: src/mem/cache/tags/split_lru.cc: src/mem/cache/tags/split_lru.hh: src/mem/packet.cc: src/mem/packet.hh: src/mem/physical.cc: src/mem/physical.hh: src/mem/tport.cc: More major reorg. Seems to work for atomic mode now, timing mode still broken. --HG-- extra : convert_revision : 7e70dfc4a752393b911880ff028271433855ae87
2007-05-22Merge vm1.(none):/home/stever/bk/newmem-headSteve Reinhardt
into vm1.(none):/home/stever/bk/newmem-cache2 src/mem/cache/base_cache.hh: Manual conflict resolution. --HG-- extra : convert_revision : 5ebfd7abb4f978caa88bf43d25935869edfc6b9f
2007-05-21Change getDeviceAddressRanges to use bool for snoop arg.Steve Reinhardt
--HG-- extra : convert_revision : 832e52ba80cbab2f5bb6d5b5977a499d41b4d638
2007-05-18Merge vm1.(none):/home/stever/bk/newmem-headSteve Reinhardt
into vm1.(none):/home/stever/bk/newmem-cache2 src/mem/bridge.cc: SCCS merged --HG-- extra : convert_revision : 9492be56a305afe88f28a77c3b23e80ce6aa81b3
2007-05-18First set of changes for reorganized cache coherence support.Steve Reinhardt
Compiles but doesn't work... committing just so I can merge (stupid bk!). src/mem/bridge.cc: Get rid of SNOOP_COMMIT. src/mem/bus.cc: src/mem/packet.hh: Get rid of SNOOP_COMMIT & two-pass snoop. First bits of EXPRESS_SNOOP support. src/mem/cache/base_cache.cc: src/mem/cache/base_cache.hh: src/mem/cache/cache.hh: src/mem/cache/cache_impl.hh: src/mem/cache/miss/blocking_buffer.cc: src/mem/cache/miss/miss_queue.cc: src/mem/cache/prefetch/base_prefetcher.cc: Big reorg of ports and port-related functions & events. src/mem/cache/cache.cc: src/mem/cache/cache_builder.cc: src/mem/cache/coherence/SConscript: Get rid of UniCoherence object. --HG-- extra : convert_revision : 7672434fa3115c9b1c94686f497e57e90413b7c3
2007-05-15hopefully the final hacky change to make the bus bridge work okAli Saidi
cache blocks that get dmaed ARE NOT marked invalid in the caches so it's a performance issue here src/mem/bridge.cc: src/mem/bridge.hh: hopefully the final hacky change to make the bus bridge work ok --HG-- extra : convert_revision : 62cbc65c74d1a84199f0a376546ec19994c5899c
2007-05-13fix handling of atomic packetsAli Saidi
fix up code for counting requests and responses --HG-- extra : convert_revision : 0d70981ee41c5d9c36cad01bd505281a096f6119
2007-05-09add a backoff algorithm when nacks are received by devicesAli Saidi
add seperate response buffers and request queue sizes in bus bridge add delay to respond to a nack in the bus bridge src/dev/i8254xGBe.cc: src/dev/ide_ctrl.cc: src/dev/ns_gige.cc: src/dev/pcidev.hh: src/dev/sinic.cc: add backoff delay parameters src/dev/io_device.cc: src/dev/io_device.hh: add a backoff algorithm when nacks are received. src/mem/bridge.cc: src/mem/bridge.hh: add seperate response buffers and request queue sizes add a new parameters to specify how long before a nack in ready to go after a packet that needs to be nacked is received src/mem/cache/cache_impl.hh: assert on the src/mem/tport.cc: add a friendly assert to make sure the packet was inserted into the list --HG-- extra : convert_revision : 3595ad932015a4ce2bb72772da7850ad91bd09b1
2007-05-07the bridge never returns false when recvTiming() is called on its ports now, ↵Ali Saidi
it always returns true and nacks the packet if there isn't sufficient buffer space fix the timing cpu to handle receiving a nacked packet src/cpu/simple/timing.cc: make the timing cpu handle receiving a nacked packet src/mem/bridge.cc: src/mem/bridge.hh: the bridge never returns false when recvTiming() is called on its ports now, it always returns true and nacks the packet if there isn't sufficient buffer space --HG-- extra : convert_revision : 5e12d0cf6ce985a5f72bcb7ce26c83a76c34c50a