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authorRon Dreslinski <rdreslin@umich.edu>2006-10-19 19:00:27 -0400
committerRon Dreslinski <rdreslin@umich.edu>2006-10-19 19:00:27 -0400
commit39d24f7241e0645bd4cf1e71d37be9b4e913cb9b (patch)
treeaafa12f68f05e6a70a330853deb6e74ee6c14520 /src/mem/cache
parent5bcdc74fe20f17f1bcacf35473d290edc4f87aa5 (diff)
downloadgem5-39d24f7241e0645bd4cf1e71d37be9b4e913cb9b.tar.xz
Always get the functional access from the highest level of cache first.
src/mem/cache/cache_impl.hh: Get the read data from the highest level of cache on a functional access --HG-- extra : convert_revision : 7437ac46fb40f3ea3b42197a1aa8aec62af60181
Diffstat (limited to 'src/mem/cache')
-rw-r--r--src/mem/cache/cache_impl.hh241
1 files changed, 120 insertions, 121 deletions
diff --git a/src/mem/cache/cache_impl.hh b/src/mem/cache/cache_impl.hh
index 520e5abb5..8683352db 100644
--- a/src/mem/cache/cache_impl.hh
+++ b/src/mem/cache/cache_impl.hh
@@ -536,6 +536,13 @@ Cache<TagStore,Buffering,Coherence>::probe(Packet * &pkt, bool update,
}
}
+ if (!update && (pkt->isWrite() || (otherSidePort == cpuSidePort))) {
+ // Still need to change data in all locations.
+ otherSidePort->sendFunctional(pkt);
+ if (pkt->isRead() && pkt->result == Packet::Success)
+ return 0;
+ }
+
PacketList writebacks;
int lat;
BlkType *blk = tags->handleAccess(pkt, lat, writebacks, update);
@@ -544,83 +551,48 @@ Cache<TagStore,Buffering,Coherence>::probe(Packet * &pkt, bool update,
pkt->getAddr() & (((ULL(1))<<48)-1), (blk) ? "hit" : "miss",
pkt->getAddr() & ~((Addr)blkSize - 1));
- if (!blk) {
- // Need to check for outstanding misses and writes
- Addr blk_addr = pkt->getAddr() & ~(blkSize - 1);
-
- // There can only be one matching outstanding miss.
- MSHR* mshr = missQueue->findMSHR(blk_addr);
-
- // There can be many matching outstanding writes.
- std::vector<MSHR*> writes;
- missQueue->findWrites(blk_addr, writes);
-
- if (!update) {
- otherSidePort->sendFunctional(pkt);
-
- // Check for data in MSHR and writebuffer.
- if (mshr) {
- warn("Found outstanding miss on an non-update probe");
- MSHR::TargetList *targets = mshr->getTargetList();
- MSHR::TargetList::iterator i = targets->begin();
- MSHR::TargetList::iterator end = targets->end();
- for (; i != end; ++i) {
- Packet * target = *i;
- // If the target contains data, and it overlaps the
- // probed request, need to update data
- if (target->isWrite() && target->intersect(pkt)) {
- uint8_t* pkt_data;
- uint8_t* write_data;
- int data_size;
- if (target->getAddr() < pkt->getAddr()) {
- int offset = pkt->getAddr() - target->getAddr();
- pkt_data = pkt->getPtr<uint8_t>();
- write_data = target->getPtr<uint8_t>() + offset;
- data_size = target->getSize() - offset;
- assert(data_size > 0);
- if (data_size > pkt->getSize())
- data_size = pkt->getSize();
- } else {
- int offset = target->getAddr() - pkt->getAddr();
- pkt_data = pkt->getPtr<uint8_t>() + offset;
- write_data = target->getPtr<uint8_t>();
- data_size = pkt->getSize() - offset;
- assert(data_size > pkt->getSize());
- if (data_size > target->getSize())
- data_size = target->getSize();
- }
-
- if (pkt->isWrite()) {
- memcpy(pkt_data, write_data, data_size);
- } else {
- memcpy(write_data, pkt_data, data_size);
- }
- }
- }
- }
- for (int i = 0; i < writes.size(); ++i) {
- Packet * write = writes[i]->pkt;
- if (write->intersect(pkt)) {
- warn("Found outstanding write on an non-update probe");
+
+ // Need to check for outstanding misses and writes
+ Addr blk_addr = pkt->getAddr() & ~(blkSize - 1);
+
+ // There can only be one matching outstanding miss.
+ MSHR* mshr = missQueue->findMSHR(blk_addr);
+
+ // There can be many matching outstanding writes.
+ std::vector<MSHR*> writes;
+ missQueue->findWrites(blk_addr, writes);
+
+ if (!update) {
+ // Check for data in MSHR and writebuffer.
+ if (mshr) {
+ warn("Found outstanding miss on an non-update probe");
+ MSHR::TargetList *targets = mshr->getTargetList();
+ MSHR::TargetList::iterator i = targets->begin();
+ MSHR::TargetList::iterator end = targets->end();
+ for (; i != end; ++i) {
+ Packet * target = *i;
+ // If the target contains data, and it overlaps the
+ // probed request, need to update data
+ if (target->isWrite() && target->intersect(pkt)) {
uint8_t* pkt_data;
uint8_t* write_data;
int data_size;
- if (write->getAddr() < pkt->getAddr()) {
- int offset = pkt->getAddr() - write->getAddr();
+ if (target->getAddr() < pkt->getAddr()) {
+ int offset = pkt->getAddr() - target->getAddr();
pkt_data = pkt->getPtr<uint8_t>();
- write_data = write->getPtr<uint8_t>() + offset;
- data_size = write->getSize() - offset;
+ write_data = target->getPtr<uint8_t>() + offset;
+ data_size = target->getSize() - offset;
assert(data_size > 0);
if (data_size > pkt->getSize())
data_size = pkt->getSize();
} else {
- int offset = write->getAddr() - pkt->getAddr();
+ int offset = target->getAddr() - pkt->getAddr();
pkt_data = pkt->getPtr<uint8_t>() + offset;
- write_data = write->getPtr<uint8_t>();
+ write_data = target->getPtr<uint8_t>();
data_size = pkt->getSize() - offset;
assert(data_size > pkt->getSize());
- if (data_size > write->getSize())
- data_size = write->getSize();
+ if (data_size > target->getSize())
+ data_size = target->getSize();
}
if (pkt->isWrite()) {
@@ -628,77 +600,108 @@ Cache<TagStore,Buffering,Coherence>::probe(Packet * &pkt, bool update,
} else {
memcpy(write_data, pkt_data, data_size);
}
-
}
}
- return 0;
- } else {
- // update the cache state and statistics
- if (mshr || !writes.empty()){
- // Can't handle it, return pktuest unsatisfied.
- panic("Atomic access ran into outstanding MSHR's or WB's!");
+ }
+ for (int i = 0; i < writes.size(); ++i) {
+ Packet * write = writes[i]->pkt;
+ if (write->intersect(pkt)) {
+ warn("Found outstanding write on an non-update probe");
+ uint8_t* pkt_data;
+ uint8_t* write_data;
+ int data_size;
+ if (write->getAddr() < pkt->getAddr()) {
+ int offset = pkt->getAddr() - write->getAddr();
+ pkt_data = pkt->getPtr<uint8_t>();
+ write_data = write->getPtr<uint8_t>() + offset;
+ data_size = write->getSize() - offset;
+ assert(data_size > 0);
+ if (data_size > pkt->getSize())
+ data_size = pkt->getSize();
+ } else {
+ int offset = write->getAddr() - pkt->getAddr();
+ pkt_data = pkt->getPtr<uint8_t>() + offset;
+ write_data = write->getPtr<uint8_t>();
+ data_size = pkt->getSize() - offset;
+ assert(data_size > pkt->getSize());
+ if (data_size > write->getSize())
+ data_size = write->getSize();
+ }
+
+ if (pkt->isWrite()) {
+ memcpy(pkt_data, write_data, data_size);
+ } else {
+ memcpy(write_data, pkt_data, data_size);
+ }
+
}
- if (!pkt->req->isUncacheable()) {
+ }
+ } else if (!blk) {
+ // update the cache state and statistics
+ if (mshr || !writes.empty()){
+ // Can't handle it, return pktuest unsatisfied.
+ panic("Atomic access ran into outstanding MSHR's or WB's!");
+ }
+ if (!pkt->req->isUncacheable()) {
// Fetch the cache block to fill
- BlkType *blk = tags->findBlock(pkt);
- Packet::Command temp_cmd = coherence->getBusCmd(pkt->cmd,
- (blk)? blk->status : 0);
+ BlkType *blk = tags->findBlock(pkt);
+ Packet::Command temp_cmd = coherence->getBusCmd(pkt->cmd,
+ (blk)? blk->status : 0);
- Packet * busPkt = new Packet(pkt->req,temp_cmd, -1, blkSize);
+ Packet * busPkt = new Packet(pkt->req,temp_cmd, -1, blkSize);
- busPkt->allocate();
+ busPkt->allocate();
- busPkt->time = curTick;
+ busPkt->time = curTick;
- DPRINTF(Cache, "Sending a atomic %s for %x blk_addr: %x\n",
- busPkt->cmdString(),
- busPkt->getAddr() & (((ULL(1))<<48)-1),
- busPkt->getAddr() & ~((Addr)blkSize - 1));
+ DPRINTF(Cache, "Sending a atomic %s for %x blk_addr: %x\n",
+ busPkt->cmdString(),
+ busPkt->getAddr() & (((ULL(1))<<48)-1),
+ busPkt->getAddr() & ~((Addr)blkSize - 1));
- lat = memSidePort->sendAtomic(busPkt);
+ lat = memSidePort->sendAtomic(busPkt);
- //Be sure to flip the response to a request for coherence
- if (busPkt->needsResponse()) {
- busPkt->makeAtomicResponse();
- }
+ //Be sure to flip the response to a request for coherence
+ if (busPkt->needsResponse()) {
+ busPkt->makeAtomicResponse();
+ }
/* if (!(busPkt->flags & SATISFIED)) {
- // blocked at a higher level, just return
- return 0;
- }
+// blocked at a higher level, just return
+return 0;
+}
*/ misses[pkt->cmdToIndex()][0/*pkt->req->getThreadNum()*/]++;
- CacheBlk::State old_state = (blk) ? blk->status : 0;
- CacheBlk::State new_state =
- coherence->getNewState(busPkt, old_state);
- DPRINTF(Cache,
+ CacheBlk::State old_state = (blk) ? blk->status : 0;
+ CacheBlk::State new_state =
+ coherence->getNewState(busPkt, old_state);
+ DPRINTF(Cache,
"Receive response:%s for blk addr %x in state %i\n",
- busPkt->cmdString(),
- busPkt->getAddr() & (((ULL(1))<<48)-1), old_state);
- if (old_state != new_state)
+ busPkt->cmdString(),
+ busPkt->getAddr() & (((ULL(1))<<48)-1), old_state);
+ if (old_state != new_state)
DPRINTF(Cache, "Block for blk addr %x moving from "
"state %i to %i\n",
busPkt->getAddr() & (((ULL(1))<<48)-1),
old_state, new_state);
- tags->handleFill(blk, busPkt,
- new_state,
- writebacks, pkt);
- //Free the packet
- delete busPkt;
-
- // Handle writebacks if needed
- while (!writebacks.empty()){
- Packet *wbPkt = writebacks.front();
- memSidePort->sendAtomic(wbPkt);
- writebacks.pop_front();
- delete wbPkt;
- }
- return lat + hitLatency;
- } else {
- return memSidePort->sendAtomic(pkt);
+ tags->handleFill(blk, busPkt,
+ new_state,
+ writebacks, pkt);
+ //Free the packet
+ delete busPkt;
+
+ // Handle writebacks if needed
+ while (!writebacks.empty()){
+ Packet *wbPkt = writebacks.front();
+ memSidePort->sendAtomic(wbPkt);
+ writebacks.pop_front();
+ delete wbPkt;
}
+ return lat + hitLatency;
+ } else {
+ return memSidePort->sendAtomic(pkt);
}
} else {
// There was a cache hit.
@@ -708,12 +711,8 @@ Cache<TagStore,Buffering,Coherence>::probe(Packet * &pkt, bool update,
writebacks.pop_front();
}
- if (update) {
- hits[pkt->cmdToIndex()][0/*pkt->req->getThreadNum()*/]++;
- } else if (pkt->isWrite()) {
- // Still need to change data in all locations.
- otherSidePort->sendFunctional(pkt);
- }
+ hits[pkt->cmdToIndex()][0/*pkt->req->getThreadNum()*/]++;
+
return hitLatency;
}
fatal("Probe not handled.\n");