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Diffstat (limited to 'src/mem/cache/coherence/coherence_protocol.hh')
| -rw-r--r-- | src/mem/cache/coherence/coherence_protocol.hh | 258 |
1 files changed, 0 insertions, 258 deletions
diff --git a/src/mem/cache/coherence/coherence_protocol.hh b/src/mem/cache/coherence/coherence_protocol.hh deleted file mode 100644 index e5d48ec2d..000000000 --- a/src/mem/cache/coherence/coherence_protocol.hh +++ /dev/null @@ -1,258 +0,0 @@ -/* - * Copyright (c) 2002-2005 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: Erik Hallnor - * Ron Dreslinski - * Steve Reinhardt - */ - -/** - * @file - * Declaration of CoherenceProcotol a basic coherence policy. - */ -#ifndef __COHERENCE_PROTOCOL_HH__ -#define __COHERENCE_PROTOCOL_HH__ - -#include <string> - -#include "base/statistics.hh" -#include "enums/Coherence.hh" -#include "mem/cache/cache_blk.hh" -#include "mem/packet.hh" -#include "sim/sim_object.hh" - -class BaseCache; -class MSHR; - -/** - * A simple coherence policy for the memory hierarchy. Currently implements - * MSI, MESI, and MOESI protocols. - */ -class CoherenceProtocol : public SimObject -{ - public: - /** - * Contruct and initialize this policy. - * @param name The name of this policy. - * @param protocol The string representation of the protocol to use. - * @param doUpgrades True if bus upgrades should be used. - */ - CoherenceProtocol(const std::string &name, Enums::Coherence protocol, - const bool doUpgrades); - - /** - * Destructor. - */ - virtual ~CoherenceProtocol() {}; - - /** - * Register statistics - */ - virtual void regStats(); - - /** - * Get the proper bus command for the given command and status. - * @param cmd The request's command. - * @param status The current state of the cache block. - * @param mshr The MSHR matching the request. - * @return The proper bus command, as determined by the protocol. - */ - MemCmd getBusCmd(MemCmd cmd, CacheBlk::State status, - MSHR *mshr = NULL); - - /** - * Return the proper state given the current state and the bus response. - * @param pkt The bus response. - * @param oldState The current block state. - * @return The new state. - */ - CacheBlk::State getNewState(PacketPtr &pkt, - CacheBlk::State oldState); - - /** - * Handle snooped bus requests. - * @param cache The cache that snooped the request. - * @param pkt The snooped bus request. - * @param blk The cache block corresponding to the request, if any. - * @param mshr The MSHR corresponding to the request, if any. - * @param new_state The new coherence state of the block. - * @return True if the request should be satisfied locally. - */ - bool handleBusRequest(BaseCache *cache, PacketPtr &pkt, CacheBlk *blk, - MSHR *mshr, CacheBlk::State &new_state); - - protected: - /** Snoop function type. */ - typedef bool (*SnoopFuncType)(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - // - // Standard snoop transition functions - // - - /** - * Do nothing transition. - */ - static bool nullTransition(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Invalid transition, basically panic. - */ - static bool invalidTransition(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Invalidate block, move to Invalid state. - */ - static bool invalidateTrans(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Supply data, no state transition. - */ - static bool supplyTrans(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Supply data and go to Shared state. - */ - static bool supplyAndGotoSharedTrans(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Supply data and go to Owned state. - */ - static bool supplyAndGotoOwnedTrans(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Invalidate block, supply data, and go to Invalid state. - */ - static bool supplyAndInvalidateTrans(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Assert the shared line for a block that is shared/exclusive. - */ - static bool assertShared(BaseCache *, PacketPtr &, CacheBlk *, - MSHR *, CacheBlk::State&); - - /** - * Definition of protocol state transitions. - */ - class StateTransition - { - friend class CoherenceProtocol; - - /** The bus command of this transition. */ - Packet::Command busCmd; - /** The state to transition to. */ - int newState; - /** The snoop function for this transition. */ - SnoopFuncType snoopFunc; - - /** - * Constructor, defaults to invalid transition. - */ - StateTransition(); - - /** - * Initialize bus command. - * @param cmd The bus command to use. - */ - void onRequest(Packet::Command cmd) - { - busCmd = cmd; - } - - /** - * Set the transition state. - * @param s The new state. - */ - void onResponse(CacheBlk::State s) - { - newState = s; - } - - /** - * Initialize the snoop function. - * @param f The new snoop function. - */ - void onSnoop(SnoopFuncType f) - { - snoopFunc = f; - } - }; - - friend class CoherenceProtocol::StateTransition; - - /** Mask to select status bits relevant to coherence protocol. */ - static const int stateMask = BlkValid | BlkWritable | BlkDirty; - - /** The Modified (M) state. */ - static const int Modified = BlkValid | BlkWritable | BlkDirty; - /** The Owned (O) state. */ - static const int Owned = BlkValid | BlkDirty; - /** The Exclusive (E) state. */ - static const int Exclusive = BlkValid | BlkWritable; - /** The Shared (S) state. */ - static const int Shared = BlkValid; - /** The Invalid (I) state. */ - static const int Invalid = 0; - - /** - * Maximum state encoding value (used to size transition lookup - * table). Could be more than number of states, depends on - * encoding of status bits. - */ - static const int stateMax = stateMask; - - /** - * The table of all possible transitions, organized by starting state and - * request command. - */ - StateTransition transitionTable[stateMax+1][MemCmd::NUM_MEM_CMDS]; - - /** - * @addtogroup CoherenceStatistics - * @{ - */ - /** - * State accesses from parent cache. - */ - Stats::Scalar<> requestCount[stateMax+1][MemCmd::NUM_MEM_CMDS]; - /** - * State accesses from snooped requests. - */ - Stats::Scalar<> snoopCount[stateMax+1][MemCmd::NUM_MEM_CMDS]; - /** - * @} - */ -}; - -#endif // __COHERENCE_PROTOCOL_HH__ |