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Refactor coherence state table initialization.

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--HG--
extra : convert_revision : eb36dd2cc1463e5076f4758a59cf68cc6b2bafc5
This commit is contained in:
Steve Reinhardt 2006-10-21 13:43:14 -07:00
parent fdad936f79
commit 1e6aa0d0d0
2 changed files with 91 additions and 174 deletions
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245
src/mem/cache/coherence/coherence_protocol.cc vendored
View file

@ -206,8 +206,7 @@ bool
CoherenceProtocol::supplyTrans(BaseCache *cache, PacketPtr &pkt,
CacheBlk *blk,
MSHR *mshr,
CacheBlk::State & new_state
)
CacheBlk::State & new_state)
{
return true;
}
@ -263,182 +262,106 @@ CoherenceProtocol::CoherenceProtocol(const string &name,
const bool doUpgrades)
: SimObject(name)
{
if ((protocol == "mosi" || protocol == "moesi") && !doUpgrades) {
cerr << "CoherenceProtocol: ownership protocols require upgrade transactions"
<< "(write miss on owned block generates ReadExcl, which will clobber dirty block)"
<< endl;
fatal("");
// 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);
}
Packet::Command writeToSharedCmd = doUpgrades ? Packet::UpgradeReq : Packet::ReadExReq;
Packet::Command writeToSharedResp = doUpgrades ? Packet::UpgradeReq : Packet::ReadExResp;
bool hasOwned = (protocol == "mosi" || protocol == "moesi");
bool hasExclusive = (protocol == "mesi" || protocol == "moesi");
//@todo add in hardware prefetch to this list
if (protocol == "msi") {
// incoming requests: specify outgoing bus request
transitionTable[Invalid][Packet::ReadReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::WriteReq].onRequest(Packet::ReadExReq);
transitionTable[Shared][Packet::WriteReq].onRequest(writeToSharedCmd);
//Prefetching causes a read
transitionTable[Invalid][Packet::SoftPFReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::HardPFReq].onRequest(Packet::ReadReq);
// on response to given request: specify new state
transitionTable[Invalid][Packet::ReadResp].onResponse(Shared);
transitionTable[Invalid][Packet::ReadExResp].onResponse(Modified);
transitionTable[Shared][writeToSharedResp].onResponse(Modified);
// bus snoop transition functions
transitionTable[Invalid][Packet::ReadReq].onSnoop(nullTransition);
transitionTable[Invalid][Packet::ReadExReq].onSnoop(nullTransition);
transitionTable[Shared][Packet::ReadReq].onSnoop(nullTransition);
transitionTable[Shared][Packet::ReadExReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::ReadExReq].onSnoop(supplyAndInvalidateTrans);
transitionTable[Modified][Packet::ReadReq].onSnoop(supplyAndGotoSharedTrans);
//Tansitions on seeing a DMA (writeInv(samelevel) or DMAInv)
transitionTable[Invalid][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Invalid][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
if (doUpgrades) {
transitionTable[Invalid][Packet::UpgradeReq].onSnoop(nullTransition);
transitionTable[Shared][Packet::UpgradeReq].onSnoop(invalidateTrans);
}
if (hasOwned && !doUpgrades) {
fatal("CoherenceProtocol: ownership protocols require upgrade "
"transactions\n(write miss on owned block generates ReadExcl, "
"which will clobber dirty block)\n");
}
else if(protocol == "mesi") {
// incoming requests: specify outgoing bus request
transitionTable[Invalid][Packet::ReadReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::WriteReq].onRequest(Packet::ReadExReq);
transitionTable[Shared][Packet::WriteReq].onRequest(writeToSharedCmd);
//Prefetching causes a read
transitionTable[Invalid][Packet::SoftPFReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::HardPFReq].onRequest(Packet::ReadReq);
// set up a few shortcuts to save typing & visual clutter
typedef Packet P;
StateTransition (&tt)[stateMax+1][NUM_MEM_CMDS] = transitionTable;
// on response to given request: specify new state
transitionTable[Invalid][Packet::ReadResp].onResponse(Exclusive);
//It will move into shared if the shared line is asserted in the
//getNewState function
transitionTable[Invalid][Packet::ReadExResp].onResponse(Modified);
transitionTable[Shared][writeToSharedResp].onResponse(Modified);
P::Command writeToSharedCmd = doUpgrades ? P::UpgradeReq : P::ReadExReq;
P::Command writeToSharedResp = doUpgrades ? P::UpgradeReq : P::ReadExResp;
// bus snoop transition functions
transitionTable[Invalid][Packet::ReadReq].onSnoop(nullTransition);
transitionTable[Invalid][Packet::ReadExReq].onSnoop(nullTransition);
transitionTable[Shared][Packet::ReadReq].onSnoop(assertShared);
transitionTable[Shared][Packet::ReadExReq].onSnoop(invalidateTrans);
transitionTable[Exclusive][Packet::ReadReq].onSnoop(assertShared);
transitionTable[Exclusive][Packet::ReadExReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::ReadExReq].onSnoop(supplyAndInvalidateTrans);
transitionTable[Modified][Packet::ReadReq].onSnoop(supplyAndGotoSharedTrans);
//Tansitions on seeing a DMA (writeInv(samelevel) or DMAInv)
transitionTable[Invalid][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Exclusive][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Invalid][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Exclusive][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
// Note that all transitions by default cause a panic.
// Override the valid transitions with the appropriate actions here.
if (doUpgrades) {
transitionTable[Invalid][Packet::UpgradeReq].onSnoop(nullTransition);
transitionTable[Shared][Packet::UpgradeReq].onSnoop(invalidateTrans);
}
//
// ----- incoming requests: specify outgoing bus request -----
//
tt[Invalid][P::ReadReq].onRequest(P::ReadReq);
// we only support write allocate right now
tt[Invalid][P::WriteReq].onRequest(P::ReadExReq);
tt[Shared][P::WriteReq].onRequest(writeToSharedCmd);
if (hasOwned) {
tt[Owned][P::WriteReq].onRequest(writeToSharedCmd);
}
else if(protocol == "mosi") {
// incoming requests: specify outgoing bus request
transitionTable[Invalid][Packet::ReadReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::WriteReq].onRequest(Packet::ReadExReq);
transitionTable[Shared][Packet::WriteReq].onRequest(writeToSharedCmd);
transitionTable[Owned][Packet::WriteReq].onRequest(writeToSharedCmd);
//Prefetching causes a read
transitionTable[Invalid][Packet::SoftPFReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::HardPFReq].onRequest(Packet::ReadReq);
// Prefetching causes a read
tt[Invalid][P::SoftPFReq].onRequest(P::ReadReq);
tt[Invalid][P::HardPFReq].onRequest(P::ReadReq);
// on response to given request: specify new state
transitionTable[Invalid][Packet::ReadResp].onResponse(Shared);
transitionTable[Invalid][Packet::ReadExResp].onResponse(Modified);
transitionTable[Shared][writeToSharedResp].onResponse(Modified);
transitionTable[Owned][writeToSharedResp].onResponse(Modified);
// bus snoop transition functions
transitionTable[Invalid][Packet::ReadReq].onSnoop(nullTransition);
transitionTable[Invalid][Packet::ReadExReq].onSnoop(nullTransition);
transitionTable[Invalid][Packet::UpgradeReq].onSnoop(nullTransition);
transitionTable[Shared][Packet::ReadReq].onSnoop(assertShared);
transitionTable[Shared][Packet::ReadExReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::UpgradeReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::ReadExReq].onSnoop(supplyAndInvalidateTrans);
transitionTable[Modified][Packet::ReadReq].onSnoop(supplyAndGotoOwnedTrans);
transitionTable[Owned][Packet::ReadReq].onSnoop(supplyAndGotoOwnedTrans);
transitionTable[Owned][Packet::ReadExReq].onSnoop(supplyAndInvalidateTrans);
transitionTable[Owned][Packet::UpgradeReq].onSnoop(invalidateTrans);
//Tansitions on seeing a DMA (writeInv(samelevel) or DMAInv)
transitionTable[Invalid][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Owned][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Invalid][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Owned][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
//
// ----- on response to given request: specify new state -----
//
tt[Invalid][P::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][P::ReadResp].onResponse(hasExclusive ? Exclusive: Shared);
// ...but for some reason that caused a link error...
if (hasExclusive) {
tt[Invalid][P::ReadResp].onResponse(Exclusive);
} else {
tt[Invalid][P::ReadResp].onResponse(Shared);
}
if (hasOwned) {
tt[Owned][writeToSharedResp].onResponse(Modified);
}
else if(protocol == "moesi") {
// incoming requests: specify outgoing bus request
transitionTable[Invalid][Packet::ReadReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::WriteReq].onRequest(Packet::ReadExReq);
transitionTable[Shared][Packet::WriteReq].onRequest(writeToSharedCmd);
transitionTable[Owned][Packet::WriteReq].onRequest(writeToSharedCmd);
//Prefetching causes a read
transitionTable[Invalid][Packet::SoftPFReq].onRequest(Packet::ReadReq);
transitionTable[Invalid][Packet::HardPFReq].onRequest(Packet::ReadReq);
//
// ----- bus snoop transition functions -----
//
tt[Invalid][P::ReadReq].onSnoop(nullTransition);
tt[Invalid][P::ReadExReq].onSnoop(nullTransition);
tt[Invalid][P::InvalidateReq].onSnoop(invalidateTrans);
tt[Invalid][P::WriteInvalidateReq].onSnoop(invalidateTrans);
tt[Shared][P::ReadReq].onSnoop(hasExclusive
? assertShared : nullTransition);
tt[Shared][P::ReadExReq].onSnoop(invalidateTrans);
tt[Shared][P::InvalidateReq].onSnoop(invalidateTrans);
tt[Shared][P::WriteInvalidateReq].onSnoop(invalidateTrans);
if (doUpgrades) {
tt[Invalid][P::UpgradeReq].onSnoop(nullTransition);
tt[Shared][P::UpgradeReq].onSnoop(invalidateTrans);
}
tt[Modified][P::ReadExReq].onSnoop(supplyAndInvalidateTrans);
tt[Modified][P::ReadReq].onSnoop(hasOwned
? supplyAndGotoOwnedTrans
: supplyAndGotoSharedTrans);
tt[Modified][P::InvalidateReq].onSnoop(invalidateTrans);
tt[Modified][P::WriteInvalidateReq].onSnoop(invalidateTrans);
// on response to given request: specify new state
transitionTable[Invalid][Packet::ReadResp].onResponse(Exclusive);
//It will move into shared if the shared line is asserted in the
//getNewState function
transitionTable[Invalid][Packet::ReadExResp].onResponse(Modified);
transitionTable[Shared][writeToSharedResp].onResponse(Modified);
transitionTable[Owned][writeToSharedResp].onResponse(Modified);
// bus snoop transition functions
transitionTable[Invalid][Packet::ReadReq].onSnoop(nullTransition);
transitionTable[Invalid][Packet::ReadExReq].onSnoop(nullTransition);
transitionTable[Invalid][Packet::UpgradeReq].onSnoop(nullTransition);
transitionTable[Shared][Packet::ReadReq].onSnoop(assertShared);
transitionTable[Shared][Packet::ReadExReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::UpgradeReq].onSnoop(invalidateTrans);
transitionTable[Exclusive][Packet::ReadReq].onSnoop(assertShared);
transitionTable[Exclusive][Packet::ReadExReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::ReadReq].onSnoop(supplyAndGotoOwnedTrans);
transitionTable[Modified][Packet::ReadExReq].onSnoop(supplyAndInvalidateTrans);
transitionTable[Owned][Packet::ReadReq].onSnoop(supplyAndGotoOwnedTrans);
transitionTable[Owned][Packet::ReadExReq].onSnoop(supplyAndInvalidateTrans);
transitionTable[Owned][Packet::UpgradeReq].onSnoop(invalidateTrans);
//Transitions on seeing a DMA (writeInv(samelevel) or DMAInv)
transitionTable[Invalid][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Exclusive][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Owned][Packet::InvalidateReq].onSnoop(invalidateTrans);
transitionTable[Invalid][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Shared][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Exclusive][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Modified][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
transitionTable[Owned][Packet::WriteInvalidateReq].onSnoop(invalidateTrans);
if (hasExclusive) {
tt[Exclusive][P::ReadReq].onSnoop(assertShared);
tt[Exclusive][P::ReadExReq].onSnoop(invalidateTrans);
tt[Exclusive][P::InvalidateReq].onSnoop(invalidateTrans);
tt[Exclusive][P::WriteInvalidateReq].onSnoop(invalidateTrans);
}
else {
cerr << "CoherenceProtocol: unrecognized protocol " << protocol
<< endl;
fatal("");
if (hasOwned) {
tt[Owned][P::ReadReq].onSnoop(supplyAndGotoOwnedTrans);
tt[Owned][P::ReadExReq].onSnoop(supplyAndInvalidateTrans);
tt[Owned][P::UpgradeReq].onSnoop(invalidateTrans);
tt[Owned][P::InvalidateReq].onSnoop(invalidateTrans);
tt[Owned][P::WriteInvalidateReq].onSnoop(invalidateTrans);
}
// @todo add in hardware prefetch to this list
}

20
src/mem/cache/coherence/coherence_protocol.hh vendored
View file

@ -211,31 +211,25 @@ class CoherenceProtocol : public SimObject
friend class CoherenceProtocol::StateTransition;
/** Mask to select status bits relevant to coherence protocol. */
const static CacheBlk::State
stateMask = BlkValid | BlkWritable | BlkDirty;
static const int stateMask = BlkValid | BlkWritable | BlkDirty;
/** The Modified (M) state. */
const static CacheBlk::State
Modified = BlkValid | BlkWritable | BlkDirty;
static const int Modified = BlkValid | BlkWritable | BlkDirty;
/** The Owned (O) state. */
const static CacheBlk::State
Owned = BlkValid | BlkDirty;
static const int Owned = BlkValid | BlkDirty;
/** The Exclusive (E) state. */
const static CacheBlk::State
Exclusive = BlkValid | BlkWritable;
static const int Exclusive = BlkValid | BlkWritable;
/** The Shared (S) state. */
const static CacheBlk::State
Shared = BlkValid;
static const int Shared = BlkValid;
/** The Invalid (I) state. */
const static CacheBlk::State
Invalid = 0;
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.
*/
const static int stateMax = stateMask;
static const int stateMax = stateMask;
/**
* The table of all possible transitions, organized by starting state and