diff options
Diffstat (limited to 'src/cpu/o3')
| -rw-r--r-- | src/cpu/o3/iew.hh | 13 | ||||
| -rw-r--r-- | src/cpu/o3/iew_impl.hh | 57 | ||||
| -rw-r--r-- | src/cpu/o3/inst_queue.hh | 25 | ||||
| -rw-r--r-- | src/cpu/o3/inst_queue_impl.hh | 68 | ||||
| -rw-r--r-- | src/cpu/o3/lsq.hh | 27 | ||||
| -rw-r--r-- | src/cpu/o3/lsq_impl.hh | 23 | ||||
| -rw-r--r-- | src/cpu/o3/lsq_unit.hh | 202 | ||||
| -rw-r--r-- | src/cpu/o3/lsq_unit_impl.hh | 40 | ||||
| -rw-r--r-- | src/cpu/o3/mem_dep_unit.hh | 4 | ||||
| -rw-r--r-- | src/cpu/o3/mem_dep_unit_impl.hh | 4 |
10 files changed, 205 insertions, 258 deletions
diff --git a/src/cpu/o3/iew.hh b/src/cpu/o3/iew.hh index 77403b499..25114c20e 100644 --- a/src/cpu/o3/iew.hh +++ b/src/cpu/o3/iew.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010-2012 ARM Limited + * Copyright (c) 2010-2012, 2014 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -181,6 +181,12 @@ class DefaultIEW /** Re-executes all rescheduled memory instructions. */ void replayMemInst(DynInstPtr &inst); + /** Moves memory instruction onto the list of cache blocked instructions */ + void blockMemInst(DynInstPtr &inst); + + /** Notifies that the cache has become unblocked */ + void cacheUnblocked(); + /** Sends an instruction to commit through the time buffer. */ void instToCommit(DynInstPtr &inst); @@ -233,11 +239,6 @@ class DefaultIEW */ void squashDueToMemOrder(DynInstPtr &inst, ThreadID tid); - /** Sends commit proper information for a squash due to memory becoming - * blocked (younger issued instructions must be retried). - */ - void squashDueToMemBlocked(DynInstPtr &inst, ThreadID tid); - /** Sets Dispatch to blocked, and signals back to other stages to block. */ void block(ThreadID tid); diff --git a/src/cpu/o3/iew_impl.hh b/src/cpu/o3/iew_impl.hh index 0a4e147c4..448be3a74 100644 --- a/src/cpu/o3/iew_impl.hh +++ b/src/cpu/o3/iew_impl.hh @@ -530,29 +530,6 @@ DefaultIEW<Impl>::squashDueToMemOrder(DynInstPtr &inst, ThreadID tid) template<class Impl> void -DefaultIEW<Impl>::squashDueToMemBlocked(DynInstPtr &inst, ThreadID tid) -{ - DPRINTF(IEW, "[tid:%i]: Memory blocked, squashing load and younger insts, " - "PC: %s [sn:%i].\n", tid, inst->pcState(), inst->seqNum); - if (!toCommit->squash[tid] || - inst->seqNum < toCommit->squashedSeqNum[tid]) { - toCommit->squash[tid] = true; - - toCommit->squashedSeqNum[tid] = inst->seqNum; - toCommit->pc[tid] = inst->pcState(); - toCommit->mispredictInst[tid] = NULL; - - // Must include the broadcasted SN in the squash. - toCommit->includeSquashInst[tid] = true; - - ldstQueue.setLoadBlockedHandled(tid); - - wroteToTimeBuffer = true; - } -} - -template<class Impl> -void DefaultIEW<Impl>::block(ThreadID tid) { DPRINTF(IEW, "[tid:%u]: Blocking.\n", tid); @@ -610,6 +587,20 @@ DefaultIEW<Impl>::replayMemInst(DynInstPtr &inst) template<class Impl> void +DefaultIEW<Impl>::blockMemInst(DynInstPtr& inst) +{ + instQueue.blockMemInst(inst); +} + +template<class Impl> +void +DefaultIEW<Impl>::cacheUnblocked() +{ + instQueue.cacheUnblocked(); +} + +template<class Impl> +void DefaultIEW<Impl>::instToCommit(DynInstPtr &inst) { // This function should not be called after writebackInsts in a @@ -1376,15 +1367,6 @@ DefaultIEW<Impl>::executeInsts() squashDueToMemOrder(violator, tid); ++memOrderViolationEvents; - } else if (ldstQueue.loadBlocked(tid) && - !ldstQueue.isLoadBlockedHandled(tid)) { - fetchRedirect[tid] = true; - - DPRINTF(IEW, "Load operation couldn't execute because the " - "memory system is blocked. PC: %s [sn:%lli]\n", - inst->pcState(), inst->seqNum); - - squashDueToMemBlocked(inst, tid); } } else { // Reset any state associated with redirects that will not @@ -1403,17 +1385,6 @@ DefaultIEW<Impl>::executeInsts() ++memOrderViolationEvents; } - if (ldstQueue.loadBlocked(tid) && - !ldstQueue.isLoadBlockedHandled(tid)) { - DPRINTF(IEW, "Load operation couldn't execute because the " - "memory system is blocked. PC: %s [sn:%lli]\n", - inst->pcState(), inst->seqNum); - DPRINTF(IEW, "Blocked load will not be handled because " - "already squashing\n"); - - ldstQueue.setLoadBlockedHandled(tid); - } - } } diff --git a/src/cpu/o3/inst_queue.hh b/src/cpu/o3/inst_queue.hh index 212829ec1..d59d5281b 100644 --- a/src/cpu/o3/inst_queue.hh +++ b/src/cpu/o3/inst_queue.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2011-2012 ARM Limited + * Copyright (c) 2011-2012, 2014 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved. * @@ -188,11 +188,16 @@ class InstructionQueue */ DynInstPtr getInstToExecute(); - /** Returns a memory instruction that was referred due to a delayed DTB - * translation if it is now ready to execute. + /** Gets a memory instruction that was referred due to a delayed DTB + * translation if it is now ready to execute. NULL if none available. */ DynInstPtr getDeferredMemInstToExecute(); + /** Gets a memory instruction that was blocked on the cache. NULL if none + * available. + */ + DynInstPtr getBlockedMemInstToExecute(); + /** * Records the instruction as the producer of a register without * adding it to the rest of the IQ. @@ -242,6 +247,12 @@ class InstructionQueue */ void deferMemInst(DynInstPtr &deferred_inst); + /** Defers a memory instruction when it is cache blocked. */ + void blockMemInst(DynInstPtr &blocked_inst); + + /** Notify instruction queue that a previous blockage has resolved */ + void cacheUnblocked(); + /** Indicates an ordering violation between a store and a load. */ void violation(DynInstPtr &store, DynInstPtr &faulting_load); @@ -308,6 +319,14 @@ class InstructionQueue */ std::list<DynInstPtr> deferredMemInsts; + /** List of instructions that have been cache blocked. */ + std::list<DynInstPtr> blockedMemInsts; + + /** List of instructions that were cache blocked, but a retry has been seen + * since, so they can now be retried. May fail again go on the blocked list. + */ + std::list<DynInstPtr> retryMemInsts; + /** * Struct for comparing entries to be added to the priority queue. * This gives reverse ordering to the instructions in terms of diff --git a/src/cpu/o3/inst_queue_impl.hh b/src/cpu/o3/inst_queue_impl.hh index 22f384cf5..0caee41ed 100644 --- a/src/cpu/o3/inst_queue_impl.hh +++ b/src/cpu/o3/inst_queue_impl.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2011-2013 ARM Limited + * Copyright (c) 2011-2014 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved. * @@ -413,6 +413,8 @@ InstructionQueue<Impl>::resetState() nonSpecInsts.clear(); listOrder.clear(); deferredMemInsts.clear(); + blockedMemInsts.clear(); + retryMemInsts.clear(); } template <class Impl> @@ -734,13 +736,14 @@ InstructionQueue<Impl>::scheduleReadyInsts() IssueStruct *i2e_info = issueToExecuteQueue->access(0); - DynInstPtr deferred_mem_inst; - int total_deferred_mem_issued = 0; - while (total_deferred_mem_issued < totalWidth && - (deferred_mem_inst = getDeferredMemInstToExecute()) != 0) { - issueToExecuteQueue->access(0)->size++; - instsToExecute.push_back(deferred_mem_inst); - total_deferred_mem_issued++; + DynInstPtr mem_inst; + while (mem_inst = getDeferredMemInstToExecute()) { + addReadyMemInst(mem_inst); + } + + // See if any cache blocked instructions are able to be executed + while (mem_inst = getBlockedMemInstToExecute()) { + addReadyMemInst(mem_inst); } // Have iterator to head of the list @@ -751,12 +754,11 @@ InstructionQueue<Impl>::scheduleReadyInsts() // Increment the iterator. // This will avoid trying to schedule a certain op class if there are no // FUs that handle it. + int total_issued = 0; ListOrderIt order_it = listOrder.begin(); ListOrderIt order_end_it = listOrder.end(); - int total_issued = 0; - while (total_issued < (totalWidth - total_deferred_mem_issued) && - order_it != order_end_it) { + while (total_issued < totalWidth && order_it != order_end_it) { OpClass op_class = (*order_it).queueType; assert(!readyInsts[op_class].empty()); @@ -874,7 +876,7 @@ InstructionQueue<Impl>::scheduleReadyInsts() // @todo If the way deferred memory instructions are handeled due to // translation changes then the deferredMemInsts condition should be removed // from the code below. - if (total_issued || total_deferred_mem_issued || deferredMemInsts.size()) { + if (total_issued || !retryMemInsts.empty() || !deferredMemInsts.empty()) { cpu->activityThisCycle(); } else { DPRINTF(IQ, "Not able to schedule any instructions.\n"); @@ -1050,7 +1052,7 @@ template <class Impl> void InstructionQueue<Impl>::replayMemInst(DynInstPtr &replay_inst) { - memDepUnit[replay_inst->threadNumber].replay(replay_inst); + memDepUnit[replay_inst->threadNumber].replay(); } template <class Impl> @@ -1078,18 +1080,52 @@ InstructionQueue<Impl>::deferMemInst(DynInstPtr &deferred_inst) } template <class Impl> +void +InstructionQueue<Impl>::blockMemInst(DynInstPtr &blocked_inst) +{ + blocked_inst->translationStarted(false); + blocked_inst->translationCompleted(false); + + blocked_inst->clearIssued(); + blocked_inst->clearCanIssue(); + blockedMemInsts.push_back(blocked_inst); +} + +template <class Impl> +void +InstructionQueue<Impl>::cacheUnblocked() +{ + retryMemInsts.splice(retryMemInsts.end(), blockedMemInsts); + // Get the CPU ticking again + cpu->wakeCPU(); +} + +template <class Impl> typename Impl::DynInstPtr InstructionQueue<Impl>::getDeferredMemInstToExecute() { for (ListIt it = deferredMemInsts.begin(); it != deferredMemInsts.end(); ++it) { if ((*it)->translationCompleted() || (*it)->isSquashed()) { - DynInstPtr ret = *it; + DynInstPtr mem_inst = *it; deferredMemInsts.erase(it); - return ret; + return mem_inst; } } - return NULL; + return nullptr; +} + +template <class Impl> +typename Impl::DynInstPtr +InstructionQueue<Impl>::getBlockedMemInstToExecute() +{ + if (retryMemInsts.empty()) { + return nullptr; + } else { + DynInstPtr mem_inst = retryMemInsts.front(); + retryMemInsts.pop_front(); + return mem_inst; + } } template <class Impl> diff --git a/src/cpu/o3/lsq.hh b/src/cpu/o3/lsq.hh index e0ed05d7e..5d57bb52b 100644 --- a/src/cpu/o3/lsq.hh +++ b/src/cpu/o3/lsq.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2011-2012 ARM Limited + * Copyright (c) 2011-2012, 2014 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved * @@ -151,18 +151,6 @@ class LSQ { bool violation(ThreadID tid) { return thread[tid].violation(); } - /** Returns if a load is blocked due to the memory system for a specific - * thread. - */ - bool loadBlocked(ThreadID tid) - { return thread[tid].loadBlocked(); } - - bool isLoadBlockedHandled(ThreadID tid) - { return thread[tid].isLoadBlockedHandled(); } - - void setLoadBlockedHandled(ThreadID tid) - { thread[tid].setLoadBlockedHandled(); } - /** Gets the instruction that caused the memory ordering violation. */ DynInstPtr getMemDepViolator(ThreadID tid) { return thread[tid].getMemDepViolator(); } @@ -277,15 +265,6 @@ class LSQ { bool willWB(ThreadID tid) { return thread[tid].willWB(); } - /** Returns if the cache is currently blocked. */ - bool cacheBlocked() const - { return retryTid != InvalidThreadID; } - - /** Sets the retry thread id, indicating that one of the LSQUnits - * tried to access the cache but the cache was blocked. */ - void setRetryTid(ThreadID tid) - { retryTid = tid; } - /** Debugging function to print out all instructions. */ void dumpInsts() const; /** Debugging function to print out instructions from a specific thread. */ @@ -348,10 +327,6 @@ class LSQ { /** Number of Threads. */ ThreadID numThreads; - - /** The thread id of the LSQ Unit that is currently waiting for a - * retry. */ - ThreadID retryTid; }; template <class Impl> diff --git a/src/cpu/o3/lsq_impl.hh b/src/cpu/o3/lsq_impl.hh index 6e605b6a0..5d50b98ea 100644 --- a/src/cpu/o3/lsq_impl.hh +++ b/src/cpu/o3/lsq_impl.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2011-2012 ARM Limited + * Copyright (c) 2011-2012, 2014 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved * @@ -62,8 +62,7 @@ LSQ<Impl>::LSQ(O3CPU *cpu_ptr, IEW *iew_ptr, DerivO3CPUParams *params) : cpu(cpu_ptr), iewStage(iew_ptr), LQEntries(params->LQEntries), SQEntries(params->SQEntries), - numThreads(params->numThreads), - retryTid(-1) + numThreads(params->numThreads) { assert(numThreads > 0 && numThreads <= Impl::MaxThreads); @@ -175,11 +174,6 @@ LSQ<Impl>::isDrained() const drained = false; } - if (retryTid != InvalidThreadID) { - DPRINTF(Drain, "Not drained, the LSQ has blocked the caches.\n"); - drained = false; - } - return drained; } @@ -338,16 +332,11 @@ template <class Impl> void LSQ<Impl>::recvRetry() { - if (retryTid == InvalidThreadID) - { - //Squashed, so drop it - return; + iewStage->cacheUnblocked(); + + for (ThreadID tid : *activeThreads) { + thread[tid].recvRetry(); } - int curr_retry_tid = retryTid; - // Speculatively clear the retry Tid. This will get set again if - // the LSQUnit was unable to complete its access. - retryTid = -1; - thread[curr_retry_tid].recvRetry(); } template <class Impl> diff --git a/src/cpu/o3/lsq_unit.hh b/src/cpu/o3/lsq_unit.hh index fcefa42fd..cb892a4fd 100644 --- a/src/cpu/o3/lsq_unit.hh +++ b/src/cpu/o3/lsq_unit.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2012-2013 ARM Limited + * Copyright (c) 2012-2014 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -183,22 +183,6 @@ class LSQUnit { /** Returns the memory ordering violator. */ DynInstPtr getMemDepViolator(); - /** Returns if a load became blocked due to the memory system. */ - bool loadBlocked() - { return isLoadBlocked; } - - /** Clears the signal that a load became blocked. */ - void clearLoadBlocked() - { isLoadBlocked = false; } - - /** Returns if the blocked load was handled. */ - bool isLoadBlockedHandled() - { return loadBlockedHandled; } - - /** Records the blocked load as being handled. */ - void setLoadBlockedHandled() - { loadBlockedHandled = true; } - /** Returns the number of free LQ entries. */ unsigned numFreeLoadEntries(); @@ -298,7 +282,7 @@ class LSQUnit { /** Default constructor. */ LSQSenderState() : mainPkt(NULL), pendingPacket(NULL), outstanding(1), - noWB(false), isSplit(false), pktToSend(false) + noWB(false), isSplit(false), pktToSend(false), cacheBlocked(false) { } /** Instruction who initiated the access to memory. */ @@ -319,6 +303,8 @@ class LSQUnit { bool isSplit; /** Whether or not there is a packet that needs sending. */ bool pktToSend; + /** Whether or not the second packet of this split load was blocked */ + bool cacheBlocked; /** Completes a packet and returns whether the access is finished. */ inline bool complete() { return --outstanding == 0; } @@ -473,18 +459,9 @@ class LSQUnit { /** Whehter or not a store is blocked due to the memory system. */ bool isStoreBlocked; - /** Whether or not a load is blocked due to the memory system. */ - bool isLoadBlocked; - - /** Has the blocked load been handled. */ - bool loadBlockedHandled; - /** Whether or not a store is in flight. */ bool storeInFlight; - /** The sequence number of the blocked load. */ - InstSeqNum blockedLoadSeqNum; - /** The oldest load that caused a memory ordering violation. */ DynInstPtr memDepViolator; @@ -706,8 +683,10 @@ LSQUnit<Impl>::read(Request *req, Request *sreqLow, Request *sreqHigh, memcpy(data, storeQueue[store_idx].data + shift_amt, req->getSize()); - assert(!load_inst->memData); - load_inst->memData = new uint8_t[req->getSize()]; + // Allocate memory if this is the first time a load is issued. + if (!load_inst->memData) { + load_inst->memData = new uint8_t[req->getSize()]; + } if (storeQueue[store_idx].isAllZeros) memset(load_inst->memData, 0, req->getSize()); else @@ -788,116 +767,105 @@ LSQUnit<Impl>::read(Request *req, Request *sreqLow, Request *sreqHigh, DPRINTF(LSQUnit, "Doing memory access for inst [sn:%lli] PC %s\n", load_inst->seqNum, load_inst->pcState()); - assert(!load_inst->memData); - load_inst->memData = new uint8_t[req->getSize()]; + // Allocate memory if this is the first time a load is issued. + if (!load_inst->memData) { + load_inst->memData = new uint8_t[req->getSize()]; + } ++usedPorts; // if we the cache is not blocked, do cache access bool completedFirst = false; - if (!lsq->cacheBlocked()) { - MemCmd command = - req->isLLSC() ? MemCmd::LoadLockedReq : MemCmd::ReadReq; - PacketPtr data_pkt = new Packet(req, command); - PacketPtr fst_data_pkt = NULL; - PacketPtr snd_data_pkt = NULL; - - data_pkt->dataStatic(load_inst->memData); - - LSQSenderState *state = new LSQSenderState; - state->isLoad = true; - state->idx = load_idx; - state->inst = load_inst; - data_pkt->senderState = state; - - if (!TheISA::HasUnalignedMemAcc || !sreqLow) { - - // Point the first packet at the main data packet. - fst_data_pkt = data_pkt; - } else { - - // Create the split packets. - fst_data_pkt = new Packet(sreqLow, command); - snd_data_pkt = new Packet(sreqHigh, command); - - fst_data_pkt->dataStatic(load_inst->memData); - snd_data_pkt->dataStatic(load_inst->memData + sreqLow->getSize()); - - fst_data_pkt->senderState = state; - snd_data_pkt->senderState = state; + MemCmd command = req->isLLSC() ? MemCmd::LoadLockedReq : MemCmd::ReadReq; + PacketPtr data_pkt = new Packet(req, command); + PacketPtr fst_data_pkt = NULL; + PacketPtr snd_data_pkt = NULL; + + data_pkt->dataStatic(load_inst->memData); + + LSQSenderState *state = new LSQSenderState; + state->isLoad = true; + state->idx = load_idx; + state->inst = load_inst; + data_pkt->senderState = state; + + if (!TheISA::HasUnalignedMemAcc || !sreqLow) { + // Point the first packet at the main data packet. + fst_data_pkt = data_pkt; + } else { + // Create the split packets. + fst_data_pkt = new Packet(sreqLow, command); + snd_data_pkt = new Packet(sreqHigh, command); + + fst_data_pkt->dataStatic(load_inst->memData); + snd_data_pkt->dataStatic(load_inst->memData + sreqLow->getSize()); + + fst_data_pkt->senderState = state; + snd_data_pkt->senderState = state; + + state->isSplit = true; + state->outstanding = 2; + state->mainPkt = data_pkt; + } - state->isSplit = true; - state->outstanding = 2; - state->mainPkt = data_pkt; + bool successful_load = true; + if (!dcachePort->sendTimingReq(fst_data_pkt)) { + successful_load = false; + } else if (TheISA::HasUnalignedMemAcc && sreqLow) { + completedFirst = true; + + // The first packet was sent without problems, so send this one + // too. If there is a problem with this packet then the whole + // load will be squashed, so indicate this to the state object. + // The first packet will return in completeDataAccess and be + // handled there. + ++usedPorts; + if (!dcachePort->sendTimingReq(snd_data_pkt)) { + // The main packet will be deleted in completeDataAccess. + state->complete(); + // Signify to 1st half that the 2nd half was blocked via state + state->cacheBlocked = true; + successful_load = false; } + } - if (!dcachePort->sendTimingReq(fst_data_pkt)) { - // Delete state and data packet because a load retry - // initiates a pipeline restart; it does not retry. + // If the cache was blocked, or has become blocked due to the access, + // handle it. + if (!successful_load) { + if (!sreqLow) { + // Packet wasn't split, just delete main packet info delete state; - delete data_pkt->req; + delete req; delete data_pkt; - if (TheISA::HasUnalignedMemAcc && sreqLow) { - delete fst_data_pkt->req; + } + + if (TheISA::HasUnalignedMemAcc && sreqLow) { + if (!completedFirst) { + // Split packet, but first failed. Delete all state. + delete state; + delete req; + delete data_pkt; delete fst_data_pkt; - delete snd_data_pkt->req; delete snd_data_pkt; + delete sreqLow; + delete sreqHigh; sreqLow = NULL; sreqHigh = NULL; - } - - req = NULL; - - // If the access didn't succeed, tell the LSQ by setting - // the retry thread id. - lsq->setRetryTid(lsqID); - } else if (TheISA::HasUnalignedMemAcc && sreqLow) { - completedFirst = true; - - // The first packet was sent without problems, so send this one - // too. If there is a problem with this packet then the whole - // load will be squashed, so indicate this to the state object. - // The first packet will return in completeDataAccess and be - // handled there. - ++usedPorts; - if (!dcachePort->sendTimingReq(snd_data_pkt)) { - - // The main packet will be deleted in completeDataAccess. - delete snd_data_pkt->req; + } else { + // Can't delete main packet data or state because first packet + // was sent to the memory system + delete data_pkt; + delete req; + delete sreqHigh; delete snd_data_pkt; - - state->complete(); - - req = NULL; sreqHigh = NULL; - - lsq->setRetryTid(lsqID); } } - } - - // If the cache was blocked, or has become blocked due to the access, - // handle it. - if (lsq->cacheBlocked()) { - if (req) - delete req; - if (TheISA::HasUnalignedMemAcc && sreqLow && !completedFirst) { - delete sreqLow; - delete sreqHigh; - } ++lsqCacheBlocked; - // There's an older load that's already going to squash. - if (isLoadBlocked && blockedLoadSeqNum < load_inst->seqNum) - return NoFault; + iewStage->blockMemInst(load_inst); - // Record that the load was blocked due to memory. This - // load will squash all instructions after it, be - // refetched, and re-executed. - isLoadBlocked = true; - loadBlockedHandled = false; - blockedLoadSeqNum = load_inst->seqNum; // No fault occurred, even though the interface is blocked. return NoFault; } diff --git a/src/cpu/o3/lsq_unit_impl.hh b/src/cpu/o3/lsq_unit_impl.hh index b805ed4be..90092cf0e 100644 --- a/src/cpu/o3/lsq_unit_impl.hh +++ b/src/cpu/o3/lsq_unit_impl.hh @@ -1,6 +1,6 @@ /* - * Copyright (c) 2010-2013 ARM Limited + * Copyright (c) 2010-2014 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved * @@ -99,7 +99,16 @@ LSQUnit<Impl>::completeDataAccess(PacketPtr pkt) DPRINTF(IEW, "Writeback event [sn:%lli].\n", inst->seqNum); DPRINTF(Activity, "Activity: Writeback event [sn:%lli].\n", inst->seqNum); - //iewStage->ldstQueue.removeMSHR(inst->threadNumber,inst->seqNum); + if (state->cacheBlocked) { + // This is the first half of a previous split load, + // where the 2nd half blocked, ignore this response + DPRINTF(IEW, "[sn:%lli]: Response from first half of earlier " + "blocked split load recieved. Ignoring.\n", inst->seqNum); + delete state; + delete pkt->req; + delete pkt; + return; + } // If this is a split access, wait until all packets are received. if (TheISA::HasUnalignedMemAcc && !state->complete()) { @@ -140,8 +149,7 @@ LSQUnit<Impl>::completeDataAccess(PacketPtr pkt) template <class Impl> LSQUnit<Impl>::LSQUnit() : loads(0), stores(0), storesToWB(0), cacheBlockMask(0), stalled(false), - isStoreBlocked(false), isLoadBlocked(false), - loadBlockedHandled(false), storeInFlight(false), hasPendingPkt(false) + isStoreBlocked(false), storeInFlight(false), hasPendingPkt(false) { } @@ -195,11 +203,7 @@ LSQUnit<Impl>::resetState() retryPkt = NULL; memDepViolator = NULL; - blockedLoadSeqNum = 0; - stalled = false; - isLoadBlocked = false; - loadBlockedHandled = false; cacheBlockMask = ~(cpu->cacheLineSize() - 1); } @@ -632,7 +636,7 @@ LSQUnit<Impl>::executeLoad(DynInstPtr &inst) } iewStage->instToCommit(inst); iewStage->activityThisCycle(); - } else if (!loadBlocked()) { + } else { assert(inst->effAddrValid()); int load_idx = inst->lqIdx; incrLdIdx(load_idx); @@ -787,7 +791,7 @@ LSQUnit<Impl>::writebackStores() ((!needsTSO) || (!storeInFlight)) && usedPorts < cachePorts) { - if (isStoreBlocked || lsq->cacheBlocked()) { + if (isStoreBlocked) { DPRINTF(LSQUnit, "Unable to write back any more stores, cache" " is blocked!\n"); break; @@ -1024,14 +1028,6 @@ LSQUnit<Impl>::squash(const InstSeqNum &squashed_num) ++lsqSquashedLoads; } - if (isLoadBlocked) { - if (squashed_num < blockedLoadSeqNum) { - isLoadBlocked = false; - loadBlockedHandled = false; - blockedLoadSeqNum = 0; - } - } - if (memDepViolator && squashed_num < memDepViolator->seqNum) { memDepViolator = NULL; } @@ -1218,7 +1214,6 @@ LSQUnit<Impl>::sendStore(PacketPtr data_pkt) ++lsqCacheBlocked; assert(retryPkt == NULL); retryPkt = data_pkt; - lsq->setRetryTid(lsqID); return false; } return true; @@ -1244,7 +1239,6 @@ LSQUnit<Impl>::recvRetry() } retryPkt = NULL; isStoreBlocked = false; - lsq->setRetryTid(InvalidThreadID); // Send any outstanding packet. if (TheISA::HasUnalignedMemAcc && state->pktToSend) { @@ -1256,13 +1250,7 @@ LSQUnit<Impl>::recvRetry() } else { // Still blocked! ++lsqCacheBlocked; - lsq->setRetryTid(lsqID); } - } else if (isLoadBlocked) { - DPRINTF(LSQUnit, "Loads squash themselves and all younger insts, " - "no need to resend packet.\n"); - } else { - DPRINTF(LSQUnit, "Retry received but LSQ is no longer blocked.\n"); } } diff --git a/src/cpu/o3/mem_dep_unit.hh b/src/cpu/o3/mem_dep_unit.hh index 989d36ea1..a42aa13ce 100644 --- a/src/cpu/o3/mem_dep_unit.hh +++ b/src/cpu/o3/mem_dep_unit.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2012 ARM Limited + * Copyright (c) 2012, 2014 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -134,7 +134,7 @@ class MemDepUnit /** Replays all instructions that have been rescheduled by moving them to * the ready list. */ - void replay(DynInstPtr &inst); + void replay(); /** Completes a memory instruction. */ void completed(DynInstPtr &inst); diff --git a/src/cpu/o3/mem_dep_unit_impl.hh b/src/cpu/o3/mem_dep_unit_impl.hh index 009ae2b48..1e794d488 100644 --- a/src/cpu/o3/mem_dep_unit_impl.hh +++ b/src/cpu/o3/mem_dep_unit_impl.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2012 ARM Limited + * Copyright (c) 2012, 2014 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -370,7 +370,7 @@ MemDepUnit<MemDepPred, Impl>::reschedule(DynInstPtr &inst) template <class MemDepPred, class Impl> void -MemDepUnit<MemDepPred, Impl>::replay(DynInstPtr &inst) +MemDepUnit<MemDepPred, Impl>::replay() { DynInstPtr temp_inst; |