gem5/src/mem/addr_mapper.hh
Andreas Hansson f26a289295 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 04:00:35 -05:00

273 lines
7.3 KiB
C++

/*
* 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.
*
* 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: Andreas Hansson
*/
#ifndef __MEM_ADDR_MAPPER_HH__
#define __MEM_ADDR_MAPPER_HH__
#include "mem/mem_object.hh"
#include "params/AddrMapper.hh"
#include "params/RangeAddrMapper.hh"
/**
* An address mapper changes the packet addresses in going from the
* slave port side of the mapper to the master port side. When the
* slave port is queried for the address ranges, it also performs the
* necessary range updates. Note that snoop requests that travel from
* the master port (i.e. the memory side) to the slave port are
* currently not modified.
*/
class AddrMapper : public MemObject
{
public:
AddrMapper(const AddrMapperParams* params);
virtual ~AddrMapper() { }
virtual BaseMasterPort& getMasterPort(const std::string& if_name,
PortID idx = InvalidPortID);
virtual BaseSlavePort& getSlavePort(const std::string& if_name,
PortID idx = InvalidPortID);
virtual void init();
protected:
/**
* This function does the actual remapping of one address to another.
* It is pure virtual in this case to to allow any implementation
* required.
* @param addr the address to remap
* @return the new address (can be unchanged)
*/
virtual Addr remapAddr(Addr addr) const = 0;
class AddrMapperSenderState : public Packet::SenderState
{
public:
/**
* Construct a new sender state to remember the original address.
*
* @param _origAddr Address before remapping
*/
AddrMapperSenderState(Addr _origAddr) : origAddr(_origAddr)
{ }
/** Destructor */
~AddrMapperSenderState() { }
/** The original address the packet was destined for */
Addr origAddr;
};
class MapperMasterPort : public MasterPort
{
public:
MapperMasterPort(const std::string& _name, AddrMapper& _mapper)
: MasterPort(_name, &_mapper), mapper(_mapper)
{ }
protected:
void recvFunctionalSnoop(PacketPtr pkt)
{
mapper.recvFunctionalSnoop(pkt);
}
Tick recvAtomicSnoop(PacketPtr pkt)
{
return mapper.recvAtomicSnoop(pkt);
}
bool recvTimingResp(PacketPtr pkt)
{
return mapper.recvTimingResp(pkt);
}
void recvTimingSnoopReq(PacketPtr pkt)
{
mapper.recvTimingSnoopReq(pkt);
}
void recvRangeChange()
{
mapper.recvRangeChange();
}
bool isSnooping() const
{
return mapper.isSnooping();
}
void recvReqRetry()
{
mapper.recvReqRetry();
}
private:
AddrMapper& mapper;
};
/** Instance of master port, facing the memory side */
MapperMasterPort masterPort;
class MapperSlavePort : public SlavePort
{
public:
MapperSlavePort(const std::string& _name, AddrMapper& _mapper)
: SlavePort(_name, &_mapper), mapper(_mapper)
{ }
protected:
void recvFunctional(PacketPtr pkt)
{
mapper.recvFunctional(pkt);
}
Tick recvAtomic(PacketPtr pkt)
{
return mapper.recvAtomic(pkt);
}
bool recvTimingReq(PacketPtr pkt)
{
return mapper.recvTimingReq(pkt);
}
bool recvTimingSnoopResp(PacketPtr pkt)
{
return mapper.recvTimingSnoopResp(pkt);
}
AddrRangeList getAddrRanges() const
{
return mapper.getAddrRanges();
}
void recvRespRetry()
{
mapper.recvRespRetry();
}
private:
AddrMapper& mapper;
};
/** Instance of slave port, i.e. on the CPU side */
MapperSlavePort slavePort;
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);
virtual AddrRangeList getAddrRanges() const = 0;
bool isSnooping() const;
void recvReqRetry();
void recvRespRetry();
void recvRangeChange();
};
/**
* Range address mapper that maps a set of original ranges to a set of
* remapped ranges, where a specific range is of the same size
* (original and remapped), only with an offset. It's useful for cases
* where memory is mapped to two different locations
*/
class RangeAddrMapper : public AddrMapper
{
public:
RangeAddrMapper(const RangeAddrMapperParams* p);
~RangeAddrMapper() { }
AddrRangeList getAddrRanges() const;
protected:
/**
* This contains a list of ranges the should be remapped. It must
* be the exact same length as remappedRanges which describes what
* manipulation should be done to each range.
*/
std::vector<AddrRange> originalRanges;
/**
* This contains a list of ranges that addresses should be
* remapped to. See the description for originalRanges above
*/
std::vector<AddrRange> remappedRanges;
Addr remapAddr(Addr addr) const;
};
#endif //__MEM_ADDR_MAPPER_HH__