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gem5/src/mem/mport.hh

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Create a message port for sending messages as apposed to reading/writing a memory range.
2008-10-12 21:08:51 +02:00
/*
MEM: Introduce the master/slave port sub-classes in C++ 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.
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* Copyright (c) 2012 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
Create a message port for sending messages as apposed to reading/writing a memory range.
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* Copyright (c) 2008 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Gabe Black
*/
#ifndef __MEM_MPORT_HH__
#define __MEM_MPORT_HH__
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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#include "mem/mem_object.hh"
Create a message port for sending messages as apposed to reading/writing a memory range.
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#include "mem/tport.hh"
/*
* This file defines a port class which is used for sending and receiving
* messages. These messages are atomic units which don't interact and
style: remove trailing whitespace Result of running 'hg m5style --skip-all --fix-white -a'.
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* should be smaller than a cache block. This class is based on
Create a message port for sending messages as apposed to reading/writing a memory range.
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* the underpinnings of SimpleTimingPort, but it tweaks some of the external
* functions.
*/
MEM: Introduce the master/slave port sub-classes in C++ 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.
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class MessageSlavePort : public SimpleTimingPort
Create a message port for sending messages as apposed to reading/writing a memory range.
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{
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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Create a message port for sending messages as apposed to reading/writing a memory range.
2008-10-12 21:08:51 +02:00
public:
MEM: Introduce the master/slave port sub-classes in C++ 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.
2012-03-30 15:40:11 +02:00
MessageSlavePort(const std::string &name, MemObject *owner) :
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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SimpleTimingPort(name, owner)
Create a message port for sending messages as apposed to reading/writing a memory range.
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{}
MEM: Introduce the master/slave port sub-classes in C++ 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.
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virtual ~MessageSlavePort()
Create a message port for sending messages as apposed to reading/writing a memory range.
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{}
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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protected:
Create a message port for sending messages as apposed to reading/writing a memory range.
2008-10-12 21:08:51 +02:00
Tick recvAtomic(PacketPtr pkt);
virtual Tick recvMessage(PacketPtr pkt) = 0;
MEM: Introduce the master/slave port sub-classes in C++ 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.
2012-03-30 15:40:11 +02:00
};
class MessageMasterPort : public QueuedMasterPort
{
public:
MessageMasterPort(const std::string &name, MemObject *owner) :
mem: Split port retry for all different packet classes This patch fixes a long-standing isue with the port flow control. Before this patch the retry mechanism was shared between all different packet classes. As a result, a snoop response could get stuck behind a request waiting for a retry, even if the send/recv functions were split. This caused message-dependent deadlocks in stress-test scenarios. The patch splits the retry into one per packet (message) class. Thus, sendTimingReq has a corresponding recvReqRetry, sendTimingResp has recvRespRetry etc. Most of the changes to the code involve simply clarifying what type of request a specific object was accepting. The biggest change in functionality is in the cache downstream packet queue, facing the memory. This queue was shared by requests and snoop responses, and it is now split into two queues, each with their own flow control, but the same physical MasterPort. These changes fixes the previously seen deadlocks.
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QueuedMasterPort(name, owner, reqQueue, snoopRespQueue),
reqQueue(*owner, *this), snoopRespQueue(*owner, *this)
MEM: Introduce the master/slave port sub-classes in C++ 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.
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{}
virtual ~MessageMasterPort()
{}
MEM: Separate requests and responses for timing accesses 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.
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bool recvTimingResp(PacketPtr pkt) { recvResponse(pkt); return true; }
MEM: Introduce the master/slave port sub-classes in C++ 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.
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protected:
/** A packet queue for outgoing packets. */
mem: Split port retry for all different packet classes This patch fixes a long-standing isue with the port flow control. Before this patch the retry mechanism was shared between all different packet classes. As a result, a snoop response could get stuck behind a request waiting for a retry, even if the send/recv functions were split. This caused message-dependent deadlocks in stress-test scenarios. The patch splits the retry into one per packet (message) class. Thus, sendTimingReq has a corresponding recvReqRetry, sendTimingResp has recvRespRetry etc. Most of the changes to the code involve simply clarifying what type of request a specific object was accepting. The biggest change in functionality is in the cache downstream packet queue, facing the memory. This queue was shared by requests and snoop responses, and it is now split into two queues, each with their own flow control, but the same physical MasterPort. These changes fixes the previously seen deadlocks.
2015-03-02 10:00:35 +01:00
ReqPacketQueue reqQueue;
SnoopRespPacketQueue snoopRespQueue;
Create a message port for sending messages as apposed to reading/writing a memory range.
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// Accept and ignore responses.
virtual Tick recvResponse(PacketPtr pkt)
{
return 0;
}
};
#endif
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