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/*
* Copyright (c) 2012-2013, 2015, 2018-2019 ARM Limited
* Copyright (c) 2016 Google Inc.
* Copyright (c) 2017, Centre National de la Recherche Scientifique
* 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.
*
* 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
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __MEM_COMM_MONITOR_HH__
#define __MEM_COMM_MONITOR_HH__
#include "base/statistics.hh"
#include "mem/port.hh"
#include "params/CommMonitor.hh"
#include "sim/probe/mem.hh"
#include "sim/sim_object.hh"
namespace gem5
{
/**
* The communication monitor is a SimObject which can monitor statistics of
* the communication happening between two ports in the memory system.
*
* Currently the following stats are implemented: Histograms of read/write
* transactions, read/write burst lengths, read/write bandwidth,
* outstanding read/write requests, read latency and inter transaction time
* (read-read, write-write, read/write-read/write). Furthermore it allows
* to capture the number of accesses to an address over time ("heat map").
* All stats can be disabled from Python.
*/
class CommMonitor : public SimObject
{
public: // Construction & SimObject interfaces
/** Parameters of communication monitor */
using Params = CommMonitorParams;
/**
* Constructor based on the Python params
*
* @param params Python parameters
*/
CommMonitor(const Params &params);
void init() override;
void startup() override;
void regProbePoints() override;
public: // SimObject interfaces
Port &getPort(const std::string &if_name,
PortID idx=InvalidPortID) override;
private:
/**
* Sender state class for the monitor so that we can annotate
* packets with a transmit time and receive time.
*/
class CommMonitorSenderState : public Packet::SenderState
{
public:
/**
* Construct a new sender state and store the time so we can
* calculate round-trip latency.
*
* @param _transmitTime Time of packet transmission
*/
CommMonitorSenderState(Tick _transmitTime)
: transmitTime(_transmitTime)
{ }
/** Destructor */
~CommMonitorSenderState() { }
/** Tick when request is transmitted */
Tick transmitTime;
};
/**
* This is the request port of the communication monitor. All recv
* functions call a function in CommMonitor, where the
* send function of the CPU-side port is called. Besides this, these
* functions can also perform actions for capturing statistics.
*/
class MonitorRequestPort : public RequestPort
{
public:
MonitorRequestPort(const std::string& _name, CommMonitor& _mon)
: RequestPort(_name, &_mon), mon(_mon)
{ }
protected:
void recvFunctionalSnoop(PacketPtr pkt)
{
mon.recvFunctionalSnoop(pkt);
}
Tick recvAtomicSnoop(PacketPtr pkt)
{
return mon.recvAtomicSnoop(pkt);
}
bool recvTimingResp(PacketPtr pkt)
{
return mon.recvTimingResp(pkt);
}
void recvTimingSnoopReq(PacketPtr pkt)
{
mon.recvTimingSnoopReq(pkt);
}
void recvRangeChange()
{
mon.recvRangeChange();
}
bool isSnooping() const
{
return mon.isSnooping();
}
void recvReqRetry()
{
mon.recvReqRetry();
}
void recvRetrySnoopResp()
{
mon.recvRetrySnoopResp();
}
private:
CommMonitor& mon;
};
/** Instance of request port, facing the memory side */
MonitorRequestPort memSidePort;
/**
* This is the CPU-side port of the communication monitor. All recv
* functions call a function in CommMonitor, where the
* send function of the request port is called. Besides this, these
* functions can also perform actions for capturing statistics.
*/
class MonitorResponsePort : public ResponsePort
{
public:
MonitorResponsePort(const std::string& _name, CommMonitor& _mon)
: ResponsePort(_name, &_mon), mon(_mon)
{ }
protected:
void recvFunctional(PacketPtr pkt)
{
mon.recvFunctional(pkt);
}
Tick recvAtomic(PacketPtr pkt)
{
return mon.recvAtomic(pkt);
}
bool recvTimingReq(PacketPtr pkt)
{
return mon.recvTimingReq(pkt);
}
bool recvTimingSnoopResp(PacketPtr pkt)
{
return mon.recvTimingSnoopResp(pkt);
}
AddrRangeList getAddrRanges() const
{
return mon.getAddrRanges();
}
void recvRespRetry()
{
mon.recvRespRetry();
}
bool tryTiming(PacketPtr pkt)
{
return mon.tryTiming(pkt);
}
private:
CommMonitor& mon;
};
/** Instance of response port, i.e. on the CPU side */
MonitorResponsePort cpuSidePort;
void recvFunctional(PacketPtr pkt);
void recvFunctionalSnoop(PacketPtr pkt);
Tick recvAtomic(PacketPtr pkt);
Tick recvAtomicSnoop(PacketPtr pkt);
bool recvTimingReq(PacketPtr pkt);
bool recvTimingResp(PacketPtr pkt);
void recvTimingSnoopReq(PacketPtr pkt);
bool recvTimingSnoopResp(PacketPtr pkt);
void recvRetrySnoopResp();
AddrRangeList getAddrRanges() const;
bool isSnooping() const;
void recvReqRetry();
void recvRespRetry();
void recvRangeChange();
bool tryTiming(PacketPtr pkt);
/** Stats declarations, all in a struct for convenience. */
struct MonitorStats : public statistics::Group
{
/** Disable flag for burst length histograms **/
bool disableBurstLengthHists;
/** Histogram of read burst lengths */
statistics::Histogram readBurstLengthHist;
/** Histogram of write burst lengths */
statistics::Histogram writeBurstLengthHist;
/** Disable flag for the bandwidth histograms */
bool disableBandwidthHists;
/**
* Histogram for read bandwidth per sample window. The
* internal counter is an unsigned int rather than a stat.
*/
unsigned int readBytes;
statistics::Histogram readBandwidthHist;
statistics::Scalar totalReadBytes;
statistics::Formula averageReadBandwidth;
/**
* Histogram for write bandwidth per sample window. The
* internal counter is an unsigned int rather than a stat.
*/
unsigned int writtenBytes;
statistics::Histogram writeBandwidthHist;
statistics::Scalar totalWrittenBytes;
statistics::Formula averageWriteBandwidth;
/** Disable flag for latency histograms. */
bool disableLatencyHists;
/** Histogram of read request-to-response latencies */
statistics::Histogram readLatencyHist;
/** Histogram of write request-to-response latencies */
statistics::Histogram writeLatencyHist;
/** Disable flag for ITT distributions. */
bool disableITTDists;
/**
* Inter transaction time (ITT) distributions. There are
* histograms of the time between two read, write or arbitrary
* accesses. The time of a request is the tick at which the
* request is forwarded by the monitor.
*/
statistics::Distribution ittReadRead;
statistics::Distribution ittWriteWrite;
statistics::Distribution ittReqReq;
Tick timeOfLastRead;
Tick timeOfLastWrite;
Tick timeOfLastReq;
/** Disable flag for outstanding histograms. */
bool disableOutstandingHists;
/**
* Histogram of outstanding read requests. Counter for
* outstanding read requests is an unsigned integer because
* it should not be reset when stats are reset.
*/
statistics::Histogram outstandingReadsHist;
unsigned int outstandingReadReqs;
/**
* Histogram of outstanding write requests. Counter for
* outstanding write requests is an unsigned integer because
* it should not be reset when stats are reset.
*/
statistics::Histogram outstandingWritesHist;
unsigned int outstandingWriteReqs;
/** Disable flag for transaction histograms. */
bool disableTransactionHists;
/** Histogram of number of read transactions per time bin */
statistics::Histogram readTransHist;
unsigned int readTrans;
/** Histogram of number of timing write transactions per time bin */
statistics::Histogram writeTransHist;
unsigned int writeTrans;
/** Disable flag for address distributions. */
bool disableAddrDists;
/** Address mask for sources of read accesses to be captured */
const Addr readAddrMask;
/** Address mask for sources of write accesses to be captured */
const Addr writeAddrMask;
/**
* Histogram of number of read accesses to addresses over
* time.
*/
statistics::SparseHistogram readAddrDist;
/**
* Histogram of number of write accesses to addresses over
* time.
*/
statistics::SparseHistogram writeAddrDist;
/**
* Create the monitor stats and initialise all the members
* that are not statistics themselves, but used to control the
* stats or track values during a sample period.
*/
MonitorStats(statistics::Group *parent,
const CommMonitorParams &params);
void updateReqStats(const probing::PacketInfo& pkt, bool is_atomic,
bool expects_response);
void updateRespStats(const probing::PacketInfo& pkt, Tick latency,
bool is_atomic);
};
/** This function is called periodically at the end of each time bin */
void samplePeriodic();
/** Periodic event called at the end of each simulation time bin */
EventFunctionWrapper samplePeriodicEvent;
/**
*@{
* @name Configuration
*/
/** Length of simulation time bin*/
const Tick samplePeriodTicks;
/** Sample period in seconds */
const double samplePeriod;
/** @} */
/** Instantiate stats */
MonitorStats stats;
protected: // Probe points
/**
* @{
* @name Memory system probe points
*/
/** Successfully forwarded request packet */
probing::PacketUPtr ppPktReq;
/** Successfully forwarded response packet */
probing::PacketUPtr ppPktResp;
/** @} */
};
} // namespace gem5
#endif //__MEM_COMM_MONITOR_HH__