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Ruby: Updates MOESI Hammer protocol

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This patch changes the manner in which data is copied from L1 to L2 cache in
the implementation of the Hammer's cache coherence protocol. Earlier, data was
copied directly from one cache entry to another. This has been broken in to
two parts. First, the data is copied from the source cache entry to a
transaction buffer entry. Then, data is copied from the transaction buffer
entry to the destination cache entry.

This has been done to maintain the invariant - at any given instant, multiple
caches under a controller are exclusive with respect to each other.
This commit is contained in:
Nilay Vaish 2011-01-04 21:40:49 -06:00
parent 498ea0bdab
commit d36cc62c11
1 changed files with 67 additions and 56 deletions
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123
src/mem/protocol/MOESI_hammer-cache.sm
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@ -689,11 +689,22 @@ machine(L1Cache, "AMD Hammer-like protocol")
action(k_popMandatoryQueue, "k", desc="Pop mandatory queue.") {
mandatoryQueue_in.dequeue();
}
action(l_popForwardQueue, "l", desc="Pop forwareded request queue.") {
forwardToCache_in.dequeue();
}
action(hp_copyFromTBEToL2, "li", desc="Copy data from TBE to L2 cache entry.") {
getCacheEntry(address).Dirty := TBEs[address].Dirty;
getCacheEntry(address).DataBlk := TBEs[address].DataBlk;
}
action(nb_copyFromTBEToL1, "fu", desc="Copy data from TBE to L1 cache entry.") {
getCacheEntry(address).Dirty := TBEs[address].Dirty;
getCacheEntry(address).DataBlk := TBEs[address].DataBlk;
getCacheEntry(address).FromL2 := true;
}
action(m_decrementNumberOfMessages, "m", desc="Decrement the number of messages for which we're waiting") {
peek(responseToCache_in, ResponseMsg) {
assert(in_msg.Acks > 0);
@ -890,28 +901,6 @@ machine(L1Cache, "AMD Hammer-like protocol")
L2cacheMemory.deallocate(address);
}
action(ss_copyFromL1toL2, "\s", desc="Copy data block from L1 (I or D) to L2") {
if (L1DcacheMemory.isTagPresent(address)) {
static_cast(Entry, L2cacheMemory[address]).Dirty := static_cast(Entry, L1DcacheMemory[address]).Dirty;
static_cast(Entry, L2cacheMemory[address]).DataBlk := static_cast(Entry, L1DcacheMemory[address]).DataBlk;
} else {
static_cast(Entry, L2cacheMemory[address]).Dirty := static_cast(Entry, L1IcacheMemory[address]).Dirty;
static_cast(Entry, L2cacheMemory[address]).DataBlk := static_cast(Entry, L1IcacheMemory[address]).DataBlk;
}
}
action(tt_copyFromL2toL1, "\t", desc="Copy data block from L2 to L1 (I or D)") {
if (L1DcacheMemory.isTagPresent(address)) {
static_cast(Entry, L1DcacheMemory[address]).Dirty := static_cast(Entry, L2cacheMemory[address]).Dirty;
static_cast(Entry, L1DcacheMemory[address]).DataBlk := static_cast(Entry, L2cacheMemory[address]).DataBlk;
static_cast(Entry, L1DcacheMemory[address]).FromL2 := true;
} else {
static_cast(Entry, L1IcacheMemory[address]).Dirty := static_cast(Entry, L2cacheMemory[address]).Dirty;
static_cast(Entry, L1IcacheMemory[address]).DataBlk := static_cast(Entry, L2cacheMemory[address]).DataBlk;
static_cast(Entry, L1IcacheMemory[address]).FromL2 := true;
}
}
action(uu_profileMiss, "\u", desc="Profile the demand miss") {
peek(mandatoryQueue_in, CacheMsg) {
if (L1IcacheMemory.isTagPresent(address)) {
@ -956,97 +945,119 @@ machine(L1Cache, "AMD Hammer-like protocol")
// Transitions moving data between the L1 and L2 caches
transition({I, S, O, M, MM}, L1_to_L2) {
vv_allocateL2CacheBlock;
ss_copyFromL1toL2; // Not really needed for state I
i_allocateTBE;
gg_deallocateL1CacheBlock;
vv_allocateL2CacheBlock;
hp_copyFromTBEToL2;
s_deallocateTBE;
}
transition(I, Trigger_L2_to_L1D, IT) {
ii_allocateL1DCacheBlock;
tt_copyFromL2toL1; // Not really needed for state I
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
ii_allocateL1DCacheBlock;
nb_copyFromTBEToL1; // Not really needed for state I
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(S, Trigger_L2_to_L1D, ST) {
ii_allocateL1DCacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
ii_allocateL1DCacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(O, Trigger_L2_to_L1D, OT) {
ii_allocateL1DCacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
ii_allocateL1DCacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(M, Trigger_L2_to_L1D, MT) {
ii_allocateL1DCacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
ii_allocateL1DCacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(MM, Trigger_L2_to_L1D, MMT) {
ii_allocateL1DCacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
ii_allocateL1DCacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(I, Trigger_L2_to_L1I, IT) {
jj_allocateL1ICacheBlock;
tt_copyFromL2toL1; // Not really needed for state I
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
jj_allocateL1ICacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(S, Trigger_L2_to_L1I, ST) {
jj_allocateL1ICacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
jj_allocateL1ICacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(O, Trigger_L2_to_L1I, OT) {
jj_allocateL1ICacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
jj_allocateL1ICacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(M, Trigger_L2_to_L1I, MT) {
jj_allocateL1ICacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
jj_allocateL1ICacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}
transition(MM, Trigger_L2_to_L1I, MMT) {
jj_allocateL1ICacheBlock;
tt_copyFromL2toL1;
uu_profileMiss;
i_allocateTBE;
rr_deallocateL2CacheBlock;
jj_allocateL1ICacheBlock;
nb_copyFromTBEToL1;
s_deallocateTBE;
uu_profileMiss;
zz_recycleMandatoryQueue;
ll_L2toL1Transfer;
}