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Diffstat (limited to 'src/mem/cache/coherence/coherence_protocol.cc')
| -rw-r--r-- | src/mem/cache/coherence/coherence_protocol.cc | 469 |
1 files changed, 0 insertions, 469 deletions
diff --git a/src/mem/cache/coherence/coherence_protocol.cc b/src/mem/cache/coherence/coherence_protocol.cc deleted file mode 100644 index 47d2b469f..000000000 --- a/src/mem/cache/coherence/coherence_protocol.cc +++ /dev/null @@ -1,469 +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 - * Steve Reinhardt - * Ron Dreslinski - */ - -/** - * @file - * Definitions of CoherenceProtocol. - */ - -#include <string> - -#include "base/misc.hh" -#include "mem/cache/miss/mshr.hh" -#include "mem/cache/cache.hh" -#include "mem/cache/coherence/coherence_protocol.hh" -#include "sim/builder.hh" - -using namespace std; - - -CoherenceProtocol::StateTransition::StateTransition() - : busCmd(MemCmd::InvalidCmd), newState(-1), snoopFunc(invalidTransition) -{ -} - - -void -CoherenceProtocol::regStats() -{ - // Even though we count all the possible transitions in the - // requestCount and snoopCount arrays, most of these are invalid, - // so we just select the interesting ones to print here. - - requestCount[Invalid][MemCmd::ReadReq] - .name(name() + ".read_invalid") - .desc("read misses to invalid blocks") - ; - - requestCount[Invalid][MemCmd::WriteReq] - .name(name() +".write_invalid") - .desc("write misses to invalid blocks") - ; - - requestCount[Invalid][MemCmd::SoftPFReq] - .name(name() +".swpf_invalid") - .desc("soft prefetch misses to invalid blocks") - ; - - requestCount[Invalid][MemCmd::HardPFReq] - .name(name() +".hwpf_invalid") - .desc("hard prefetch misses to invalid blocks") - ; - - requestCount[Shared][MemCmd::WriteReq] - .name(name() + ".write_shared") - .desc("write misses to shared blocks") - ; - - requestCount[Owned][MemCmd::WriteReq] - .name(name() + ".write_owned") - .desc("write misses to owned blocks") - ; - - snoopCount[Shared][MemCmd::ReadReq] - .name(name() + ".snoop_read_shared") - .desc("read snoops on shared blocks") - ; - - snoopCount[Shared][MemCmd::ReadExReq] - .name(name() + ".snoop_readex_shared") - .desc("readEx snoops on shared blocks") - ; - - snoopCount[Shared][MemCmd::UpgradeReq] - .name(name() + ".snoop_upgrade_shared") - .desc("upgradee snoops on shared blocks") - ; - - snoopCount[Modified][MemCmd::ReadReq] - .name(name() + ".snoop_read_modified") - .desc("read snoops on modified blocks") - ; - - snoopCount[Modified][MemCmd::ReadExReq] - .name(name() + ".snoop_readex_modified") - .desc("readEx snoops on modified blocks") - ; - - snoopCount[Owned][MemCmd::ReadReq] - .name(name() + ".snoop_read_owned") - .desc("read snoops on owned blocks") - ; - - snoopCount[Owned][MemCmd::ReadExReq] - .name(name() + ".snoop_readex_owned") - .desc("readEx snoops on owned blocks") - ; - - snoopCount[Owned][MemCmd::UpgradeReq] - .name(name() + ".snoop_upgrade_owned") - .desc("upgrade snoops on owned blocks") - ; - - snoopCount[Exclusive][MemCmd::ReadReq] - .name(name() + ".snoop_read_exclusive") - .desc("read snoops on exclusive blocks") - ; - - snoopCount[Exclusive][MemCmd::ReadExReq] - .name(name() + ".snoop_readex_exclusive") - .desc("readEx snoops on exclusive blocks") - ; - - snoopCount[Shared][MemCmd::WriteInvalidateReq] - .name(name() + ".snoop_writeinv_shared") - .desc("WriteInvalidate snoops on shared blocks") - ; - - snoopCount[Owned][MemCmd::WriteInvalidateReq] - .name(name() + ".snoop_writeinv_owned") - .desc("WriteInvalidate snoops on owned blocks") - ; - - snoopCount[Exclusive][MemCmd::WriteInvalidateReq] - .name(name() + ".snoop_writeinv_exclusive") - .desc("WriteInvalidate snoops on exclusive blocks") - ; - - snoopCount[Modified][MemCmd::WriteInvalidateReq] - .name(name() + ".snoop_writeinv_modified") - .desc("WriteInvalidate snoops on modified blocks") - ; - - snoopCount[Invalid][MemCmd::WriteInvalidateReq] - .name(name() + ".snoop_writeinv_invalid") - .desc("WriteInvalidate snoops on invalid blocks") - ; -} - - -bool -CoherenceProtocol::invalidateTrans(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, MSHR *mshr, - CacheBlk::State & new_state) -{ - // invalidate the block - new_state = (blk->status & ~stateMask) | Invalid; - return false; -} - - -bool -CoherenceProtocol::supplyTrans(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, - MSHR *mshr, - CacheBlk::State & new_state) -{ - return true; -} - - -bool -CoherenceProtocol::supplyAndGotoSharedTrans(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, - MSHR *mshr, - CacheBlk::State & new_state) -{ - new_state = (blk->status & ~stateMask) | Shared; - pkt->assertShared(); - return supplyTrans(cache, pkt, blk, mshr, new_state); -} - - -bool -CoherenceProtocol::supplyAndGotoOwnedTrans(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, - MSHR *mshr, - CacheBlk::State & new_state) -{ - new_state = (blk->status & ~stateMask) | Owned; - pkt->assertShared(); - return supplyTrans(cache, pkt, blk, mshr, new_state); -} - - -bool -CoherenceProtocol::supplyAndInvalidateTrans(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, - MSHR *mshr, - CacheBlk::State & new_state) -{ - new_state = (blk->status & ~stateMask) | Invalid; - return supplyTrans(cache, pkt, blk, mshr, new_state); -} - -bool -CoherenceProtocol::assertShared(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, - MSHR *mshr, - CacheBlk::State & new_state) -{ - new_state = (blk->status & ~stateMask) | Shared; - pkt->assertShared(); - return false; -} - -CoherenceProtocol::CoherenceProtocol(const string &name, - const string &protocol, - const bool doUpgrades) - : SimObject(name) -{ - // Python should catch this, but in case it doesn't... - if (!(protocol == "msi" || protocol == "mesi" || - protocol == "mosi" || protocol == "moesi")) { - fatal("CoherenceProtocol: unrecognized protocol %s\n", protocol); - } - - bool hasOwned = (protocol == "mosi" || protocol == "moesi"); - bool hasExclusive = (protocol == "mesi" || protocol == "moesi"); - - if (hasOwned && !doUpgrades) { - fatal("CoherenceProtocol: ownership protocols require upgrade " - "transactions\n(write miss on owned block generates ReadExcl, " - "which will clobber dirty block)\n"); - } - - // set up a few shortcuts to save typing & visual clutter - typedef MemCmd MC; - StateTransition (&tt)[stateMax+1][MC::NUM_MEM_CMDS] = transitionTable; - - MC::Command writeToSharedCmd = - doUpgrades ? MC::UpgradeReq : MC::ReadExReq; - MC::Command writeToSharedResp = - doUpgrades ? MC::UpgradeResp : MC::ReadExResp; - - // Note that all transitions by default cause a panic. - // Override the valid transitions with the appropriate actions here. - - // - // ----- incoming requests: specify outgoing bus request ----- - // - tt[Invalid][MC::ReadReq].onRequest(MC::ReadReq); - // we only support write allocate right now - tt[Invalid][MC::WriteReq].onRequest(MC::ReadExReq); - tt[Invalid][MC::ReadExReq].onRequest(MC::ReadExReq); - tt[Invalid][MC::SwapReq].onRequest(MC::ReadExReq); - tt[Invalid][MC::UpgradeReq].onRequest(MC::UpgradeReq); - tt[Shared][MC::WriteReq].onRequest(writeToSharedCmd); - tt[Shared][MC::ReadExReq].onRequest(MC::ReadExReq); - tt[Shared][MC::SwapReq].onRequest(writeToSharedCmd); - if (hasOwned) { - tt[Owned][MC::WriteReq].onRequest(writeToSharedCmd); - tt[Owned][MC::ReadExReq].onRequest(MC::ReadExReq); - tt[Owned][MC::SwapReq].onRequest(writeToSharedCmd); - } - - // Prefetching causes a read - tt[Invalid][MC::SoftPFReq].onRequest(MC::ReadReq); - tt[Invalid][MC::HardPFReq].onRequest(MC::ReadReq); - - // - // ----- on response to given request: specify new state ----- - // - tt[Invalid][MC::ReadExResp].onResponse(Modified); - tt[Shared][writeToSharedResp].onResponse(Modified); - // Go to Exclusive state on read response if we have one (will - // move into shared if the shared line is asserted in the - // getNewState function) - // - // originally had this as: - // tt[Invalid][MC::ReadResp].onResponse(hasExclusive ? Exclusive: Shared); - // ...but for some reason that caused a link error... - if (hasExclusive) { - tt[Invalid][MC::ReadResp].onResponse(Exclusive); - } else { - tt[Invalid][MC::ReadResp].onResponse(Shared); - } - if (hasOwned) { - tt[Owned][writeToSharedResp].onResponse(Modified); - } - - // - // ----- bus snoop transition functions ----- - // - tt[Invalid][MC::ReadReq].onSnoop(nullTransition); - tt[Invalid][MC::ReadExReq].onSnoop(nullTransition); - tt[Invalid][MC::WriteInvalidateReq].onSnoop(invalidateTrans); - tt[Shared][MC::ReadReq].onSnoop(hasExclusive - ? assertShared : nullTransition); - tt[Shared][MC::ReadExReq].onSnoop(invalidateTrans); - tt[Shared][MC::WriteInvalidateReq].onSnoop(invalidateTrans); - if (doUpgrades) { - tt[Invalid][MC::UpgradeReq].onSnoop(nullTransition); - tt[Shared][MC::UpgradeReq].onSnoop(invalidateTrans); - } - tt[Modified][MC::ReadExReq].onSnoop(supplyAndInvalidateTrans); - tt[Modified][MC::ReadReq].onSnoop(hasOwned - ? supplyAndGotoOwnedTrans - : supplyAndGotoSharedTrans); - tt[Modified][MC::WriteInvalidateReq].onSnoop(invalidateTrans); - - if (hasExclusive) { - tt[Exclusive][MC::ReadReq].onSnoop(assertShared); - tt[Exclusive][MC::ReadExReq].onSnoop(invalidateTrans); - tt[Exclusive][MC::WriteInvalidateReq].onSnoop(invalidateTrans); - } - - if (hasOwned) { - tt[Owned][MC::ReadReq].onSnoop(supplyAndGotoOwnedTrans); - tt[Owned][MC::ReadExReq].onSnoop(supplyAndInvalidateTrans); - tt[Owned][MC::UpgradeReq].onSnoop(invalidateTrans); - tt[Owned][MC::WriteInvalidateReq].onSnoop(invalidateTrans); - } - - // @todo add in hardware prefetch to this list -} - - -MemCmd -CoherenceProtocol::getBusCmd(MemCmd cmdIn, CacheBlk::State state, - MSHR *mshr) -{ - state &= stateMask; - int cmd_idx = cmdIn.toInt(); - - assert(0 <= state && state <= stateMax); - assert(0 <= cmd_idx && cmd_idx < MemCmd::NUM_MEM_CMDS); - - MemCmd::Command cmdOut = transitionTable[state][cmd_idx].busCmd; - - assert(cmdOut != MemCmd::InvalidCmd); - - ++requestCount[state][cmd_idx]; - - return cmdOut; -} - - -CacheBlk::State -CoherenceProtocol::getNewState(PacketPtr pkt, CacheBlk::State oldState) -{ - CacheBlk::State state = oldState & stateMask; - int cmd_idx = pkt->cmdToIndex(); - - assert(0 <= state && state <= stateMax); - assert(0 <= cmd_idx && cmd_idx < MemCmd::NUM_MEM_CMDS); - - CacheBlk::State newState = transitionTable[state][cmd_idx].newState; - - //Check if it's exclusive and the shared line was asserted, - //then goto shared instead - if (newState == Exclusive && pkt->sharedAsserted()) { - newState = Shared; - } - - assert(newState != -1); - - //Make sure not to loose any other state information - newState = (oldState & ~stateMask) | newState; - return newState; -} - - -bool -CoherenceProtocol::handleBusRequest(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, - MSHR *mshr, - CacheBlk::State & new_state) -{ - if (blk == NULL) { - // nothing to do if we don't have a block - return false; - } - - CacheBlk::State state = blk->status & stateMask; - int cmd_idx = pkt->cmdToIndex(); - - assert(0 <= state && state <= stateMax); - assert(0 <= cmd_idx && cmd_idx < MemCmd::NUM_MEM_CMDS); - -// assert(mshr == NULL); // can't currently handle outstanding requests - //Check first if MSHR, and also insure, if there is one, that it is not in service - assert(!mshr || mshr->inService == 0); - ++snoopCount[state][cmd_idx]; - - bool ret = transitionTable[state][cmd_idx].snoopFunc(cache, pkt, blk, mshr, - new_state); - - - - return ret; -} - -bool -CoherenceProtocol::nullTransition(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, MSHR *mshr, - CacheBlk::State & new_state) -{ - // do nothing - if (blk) - new_state = blk->status; - return false; -} - - -bool -CoherenceProtocol::invalidTransition(BaseCache *cache, PacketPtr &pkt, - CacheBlk *blk, MSHR *mshr, - CacheBlk::State & new_state) -{ - panic("Invalid transition"); - return false; -} - -#ifndef DOXYGEN_SHOULD_SKIP_THIS - -BEGIN_DECLARE_SIM_OBJECT_PARAMS(CoherenceProtocol) - - Param<string> protocol; - Param<bool> do_upgrades; - -END_DECLARE_SIM_OBJECT_PARAMS(CoherenceProtocol) - - -BEGIN_INIT_SIM_OBJECT_PARAMS(CoherenceProtocol) - - INIT_PARAM(protocol, "name of coherence protocol"), - INIT_PARAM_DFLT(do_upgrades, "use upgrade transactions?", true) - -END_INIT_SIM_OBJECT_PARAMS(CoherenceProtocol) - - -CREATE_SIM_OBJECT(CoherenceProtocol) -{ - return new CoherenceProtocol(getInstanceName(), protocol, - do_upgrades); -} - -REGISTER_SIM_OBJECT("CoherenceProtocol", CoherenceProtocol) - -#endif // DOXYGEN_SHOULD_SKIP_THIS |