diff options
| -rw-r--r-- | src/cpu/o3/lsq.hh | 59 | ||||
| -rw-r--r-- | src/cpu/o3/lsq_impl.hh | 53 | ||||
| -rw-r--r-- | src/cpu/o3/lsq_unit.hh | 88 | ||||
| -rw-r--r-- | src/cpu/o3/lsq_unit_impl.hh | 51 |
4 files changed, 139 insertions, 112 deletions
diff --git a/src/cpu/o3/lsq.hh b/src/cpu/o3/lsq.hh index d5890950f..190734dc2 100644 --- a/src/cpu/o3/lsq.hh +++ b/src/cpu/o3/lsq.hh @@ -70,7 +70,7 @@ class LSQ { * to work. For now it just returns the port from one of the * threads. */ - Port *getDcachePort() { return thread[0].getDcachePort(); } + Port *getDcachePort() { return &dcachePort; } /** Sets the pointer to the list of active threads. */ void setActiveThreads(std::list<unsigned> *at_ptr); @@ -258,6 +258,15 @@ class LSQ { bool willWB(unsigned tid) { return thread[tid].willWB(); } + /** Returns if the cache is currently blocked. */ + bool cacheBlocked() + { return retryTid != -1; } + + /** Sets the retry thread id, indicating that one of the LSQUnits + * tried to access the cache but the cache was blocked. */ + void setRetryTid(int tid) + { retryTid = tid; } + /** Debugging function to print out all instructions. */ void dumpInsts(); /** Debugging function to print out instructions from a specific thread. */ @@ -274,7 +283,49 @@ class LSQ { template <class T> Fault write(RequestPtr req, T &data, int store_idx); - private: + /** DcachePort class for this LSQ. Handles doing the + * communication with the cache/memory. + */ + class DcachePort : public Port + { + protected: + /** Pointer to LSQ. */ + LSQ *lsq; + + public: + /** Default constructor. */ + DcachePort(LSQ *_lsq) + : lsq(_lsq) + { } + + protected: + /** Atomic version of receive. Panics. */ + virtual Tick recvAtomic(PacketPtr pkt); + + /** Functional version of receive. Panics. */ + virtual void recvFunctional(PacketPtr pkt); + + /** Receives status change. Other than range changing, panics. */ + virtual void recvStatusChange(Status status); + + /** Returns the address ranges of this device. */ + virtual void getDeviceAddressRanges(AddrRangeList &resp, + AddrRangeList &snoop) + { resp.clear(); snoop.clear(); } + + /** Timing version of receive. Handles writing back and + * completing the load or store that has returned from + * memory. */ + virtual bool recvTiming(PacketPtr pkt); + + /** Handles doing a retry of the previous send. */ + virtual void recvRetry(); + }; + + /** D-cache port. */ + DcachePort dcachePort; + + protected: /** The LSQ policy for SMT mode. */ LSQPolicy lsqPolicy; @@ -303,6 +354,10 @@ class LSQ { /** Number of Threads. */ unsigned numThreads; + + /** The thread id of the LSQ Unit that is currently waiting for a + * retry. */ + int retryTid; }; template <class Impl> diff --git a/src/cpu/o3/lsq_impl.hh b/src/cpu/o3/lsq_impl.hh index 89fd1a71d..4e3957029 100644 --- a/src/cpu/o3/lsq_impl.hh +++ b/src/cpu/o3/lsq_impl.hh @@ -36,9 +36,53 @@ using namespace std; template <class Impl> +Tick +LSQ<Impl>::DcachePort::recvAtomic(PacketPtr pkt) +{ + panic("O3CPU model does not work with atomic mode!"); + return curTick; +} + +template <class Impl> +void +LSQ<Impl>::DcachePort::recvFunctional(PacketPtr pkt) +{ + panic("O3CPU doesn't expect recvFunctional callback!"); +} + +template <class Impl> +void +LSQ<Impl>::DcachePort::recvStatusChange(Status status) +{ + if (status == RangeChange) + return; + + panic("O3CPU doesn't expect recvStatusChange callback!"); +} + +template <class Impl> +bool +LSQ<Impl>::DcachePort::recvTiming(PacketPtr pkt) +{ + lsq->thread[pkt->req->getThreadNum()].completeDataAccess(pkt); + return true; +} + +template <class Impl> +void +LSQ<Impl>::DcachePort::recvRetry() +{ + lsq->thread[lsq->retryTid].recvRetry(); + // Speculatively clear the retry Tid. This will get set again if + // the LSQUnit was unable to complete its access. + lsq->retryTid = -1; +} + +template <class Impl> LSQ<Impl>::LSQ(Params *params) - : LQEntries(params->LQEntries), SQEntries(params->SQEntries), - numThreads(params->numberOfThreads) + : dcachePort(this), LQEntries(params->LQEntries), + SQEntries(params->SQEntries), numThreads(params->numberOfThreads), + retryTid(-1) { DPRINTF(LSQ, "Creating LSQ object.\n"); @@ -94,7 +138,8 @@ LSQ<Impl>::LSQ(Params *params) //Initialize LSQs for (int tid=0; tid < numThreads; tid++) { - thread[tid].init(params, maxLQEntries, maxSQEntries, tid); + thread[tid].init(params, this, maxLQEntries, maxSQEntries, tid); + thread[tid].setDcachePort(&dcachePort); } } @@ -130,6 +175,8 @@ LSQ<Impl>::setCPU(O3CPU *cpu_ptr) { cpu = cpu_ptr; + dcachePort.setName(name()); + for (int tid=0; tid < numThreads; tid++) { thread[tid].setCPU(cpu_ptr); } diff --git a/src/cpu/o3/lsq_unit.hh b/src/cpu/o3/lsq_unit.hh index 4d7a8350b..a76a73f0c 100644 --- a/src/cpu/o3/lsq_unit.hh +++ b/src/cpu/o3/lsq_unit.hh @@ -64,6 +64,7 @@ class LSQUnit { typedef typename Impl::O3CPU O3CPU; typedef typename Impl::DynInstPtr DynInstPtr; typedef typename Impl::CPUPol::IEW IEW; + typedef typename Impl::CPUPol::LSQ LSQ; typedef typename Impl::CPUPol::IssueStruct IssueStruct; public: @@ -71,17 +72,12 @@ class LSQUnit { LSQUnit(); /** Initializes the LSQ unit with the specified number of entries. */ - void init(Params *params, unsigned maxLQEntries, + void init(Params *params, LSQ *lsq_ptr, unsigned maxLQEntries, unsigned maxSQEntries, unsigned id); /** Returns the name of the LSQ unit. */ std::string name() const; - /** Returns the dcache port. - * @todo: Remove this once the port moves up to the LSQ level. - */ - Port *getDcachePort() { return dcachePort; } - /** Registers statistics. */ void regStats(); @@ -92,6 +88,10 @@ class LSQUnit { void setIEW(IEW *iew_ptr) { iewStage = iew_ptr; } + /** Sets the pointer to the dcache port. */ + void setDcachePort(Port *dcache_port) + { dcachePort = dcache_port; } + /** Switches out LSQ unit. */ void switchOut(); @@ -211,6 +211,9 @@ class LSQUnit { !storeQueue[storeWBIdx].completed && !isStoreBlocked; } + /** Handles doing the retry. */ + void recvRetry(); + private: /** Writes back the instruction, sending it to IEW. */ void writeback(DynInstPtr &inst, PacketPtr pkt); @@ -221,9 +224,6 @@ class LSQUnit { /** Completes the store at the specified index. */ void completeStore(int store_idx); - /** Handles doing the retry. */ - void recvRetry(); - /** Increments the given store index (circular queue). */ inline void incrStIdx(int &store_idx); /** Decrements the given store index (circular queue). */ @@ -244,54 +244,11 @@ class LSQUnit { /** Pointer to the IEW stage. */ IEW *iewStage; - /** Pointer to memory object. */ - MemObject *mem; + /** Pointer to the LSQ. */ + LSQ *lsq; - /** DcachePort class for this LSQ Unit. Handles doing the - * communication with the cache/memory. - * @todo: Needs to be moved to the LSQ level and have some sort - * of arbitration. - */ - class DcachePort : public Port - { - protected: - /** Pointer to CPU. */ - O3CPU *cpu; - /** Pointer to LSQ. */ - LSQUnit *lsq; - - public: - /** Default constructor. */ - DcachePort(O3CPU *_cpu, LSQUnit *_lsq) - : Port(_lsq->name() + "-dport"), cpu(_cpu), lsq(_lsq) - { } - - protected: - /** Atomic version of receive. Panics. */ - virtual Tick recvAtomic(PacketPtr pkt); - - /** Functional version of receive. Panics. */ - virtual void recvFunctional(PacketPtr pkt); - - /** Receives status change. Other than range changing, panics. */ - virtual void recvStatusChange(Status status); - - /** Returns the address ranges of this device. */ - virtual void getDeviceAddressRanges(AddrRangeList &resp, - AddrRangeList &snoop) - { resp.clear(); snoop.clear(); } - - /** Timing version of receive. Handles writing back and - * completing the load or store that has returned from - * memory. */ - virtual bool recvTiming(PacketPtr pkt); - - /** Handles doing a retry of the previous send. */ - virtual void recvRetry(); - }; - - /** Pointer to the D-cache. */ - DcachePort *dcachePort; + /** Pointer to the dcache port. Used only for sending. */ + Port *dcachePort; /** Derived class to hold any sender state the LSQ needs. */ class LSQSenderState : public Packet::SenderState @@ -658,7 +615,7 @@ LSQUnit<Impl>::read(Request *req, T &data, int load_idx) } // If there's no forwarding case, then go access memory - DPRINTF(LSQUnit, "Doing functional access for inst [sn:%lli] PC %#x\n", + DPRINTF(LSQUnit, "Doing memory access for inst [sn:%lli] PC %#x\n", load_inst->seqNum, load_inst->readPC()); assert(!load_inst->memData); @@ -666,9 +623,6 @@ LSQUnit<Impl>::read(Request *req, T &data, int load_idx) ++usedPorts; - DPRINTF(LSQUnit, "Doing timing access for inst PC %#x\n", - load_inst->readPC()); - PacketPtr data_pkt = new Packet(req, Packet::ReadReq, Packet::Broadcast); data_pkt->dataStatic(load_inst->memData); @@ -678,8 +632,18 @@ LSQUnit<Impl>::read(Request *req, T &data, int load_idx) state->inst = load_inst; data_pkt->senderState = state; - // if we have a cache, do cache access too - if (!dcachePort->sendTiming(data_pkt)) { + // if we the cache is not blocked, do cache access + if (!lsq->cacheBlocked()) { + if (!dcachePort->sendTiming(data_pkt)) { + // If the access didn't succeed, tell the LSQ by setting + // the retry thread id. + lsq->setRetryTid(lsqID); + } + } + + // If the cache was blocked, or has become blocked due to the access, + // handle it. + if (lsq->cacheBlocked()) { ++lsqCacheBlocked; // There's an older load that's already going to squash. if (isLoadBlocked && blockedLoadSeqNum < load_inst->seqNum) diff --git a/src/cpu/o3/lsq_unit_impl.hh b/src/cpu/o3/lsq_unit_impl.hh index 8e951534f..85b150cd9 100644 --- a/src/cpu/o3/lsq_unit_impl.hh +++ b/src/cpu/o3/lsq_unit_impl.hh @@ -31,6 +31,7 @@ #include "config/use_checker.hh" +#include "cpu/o3/lsq.hh" #include "cpu/o3/lsq_unit.hh" #include "base/str.hh" #include "mem/packet.hh" @@ -96,46 +97,6 @@ LSQUnit<Impl>::completeDataAccess(PacketPtr pkt) } template <class Impl> -Tick -LSQUnit<Impl>::DcachePort::recvAtomic(PacketPtr pkt) -{ - panic("O3CPU model does not work with atomic mode!"); - return curTick; -} - -template <class Impl> -void -LSQUnit<Impl>::DcachePort::recvFunctional(PacketPtr pkt) -{ - panic("O3CPU doesn't expect recvFunctional callback!"); -} - -template <class Impl> -void -LSQUnit<Impl>::DcachePort::recvStatusChange(Status status) -{ - if (status == RangeChange) - return; - - panic("O3CPU doesn't expect recvStatusChange callback!"); -} - -template <class Impl> -bool -LSQUnit<Impl>::DcachePort::recvTiming(PacketPtr pkt) -{ - lsq->completeDataAccess(pkt); - return true; -} - -template <class Impl> -void -LSQUnit<Impl>::DcachePort::recvRetry() -{ - lsq->recvRetry(); -} - -template <class Impl> LSQUnit<Impl>::LSQUnit() : loads(0), stores(0), storesToWB(0), stalled(false), isStoreBlocked(false), isLoadBlocked(false), @@ -145,13 +106,15 @@ LSQUnit<Impl>::LSQUnit() template<class Impl> void -LSQUnit<Impl>::init(Params *params, unsigned maxLQEntries, +LSQUnit<Impl>::init(Params *params, LSQ *lsq_ptr, unsigned maxLQEntries, unsigned maxSQEntries, unsigned id) { DPRINTF(LSQUnit, "Creating LSQUnit%i object.\n",id); switchedOut = false; + lsq = lsq_ptr; + lsqID = id; // Add 1 for the sentinel entry (they are circular queues). @@ -168,8 +131,6 @@ LSQUnit<Impl>::init(Params *params, unsigned maxLQEntries, usedPorts = 0; cachePorts = params->cachePorts; - mem = params->mem; - memDepViolator = NULL; blockedLoadSeqNum = 0; @@ -180,7 +141,6 @@ void LSQUnit<Impl>::setCPU(O3CPU *cpu_ptr) { cpu = cpu_ptr; - dcachePort = new DcachePort(cpu, this); #if USE_CHECKER if (cpu->checker) { @@ -588,7 +548,7 @@ LSQUnit<Impl>::writebackStores() storeQueue[storeWBIdx].canWB && usedPorts < cachePorts) { - if (isStoreBlocked) { + if (isStoreBlocked || lsq->cacheBlocked()) { DPRINTF(LSQUnit, "Unable to write back any more stores, cache" " is blocked!\n"); break; @@ -911,6 +871,7 @@ LSQUnit<Impl>::recvRetry() } else { // Still blocked! ++lsqCacheBlocked; + lsq->setRetryTid(lsqID); } } else if (isLoadBlocked) { DPRINTF(LSQUnit, "Loads squash themselves and all younger insts, " |