diff options
Diffstat (limited to 'src/mem/physical.hh')
-rw-r--r-- | src/mem/physical.hh | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/src/mem/physical.hh b/src/mem/physical.hh index 02308b2ef..97bea2ec4 100644 --- a/src/mem/physical.hh +++ b/src/mem/physical.hh @@ -78,6 +78,68 @@ class PhysicalMemory : public MemObject const PhysicalMemory &operator=(const PhysicalMemory &specmem); protected: + + class LockedAddr { + public: + // on alpha, minimum LL/SC granularity is 16 bytes, so lower + // bits need to masked off. + static const Addr Addr_Mask = 0xf; + + static Addr mask(Addr paddr) { return (paddr & ~Addr_Mask); } + + Addr addr; // locked address + int cpuNum; // locking CPU + int threadNum; // locking thread ID within CPU + + // check for matching execution context + bool matchesContext(Request *req) + { + return (cpuNum == req->getCpuNum() && + threadNum == req->getThreadNum()); + } + + LockedAddr(Request *req) + : addr(mask(req->getPaddr())), + cpuNum(req->getCpuNum()), + threadNum(req->getThreadNum()) + { + } + }; + + std::list<LockedAddr> lockedAddrList; + + // helper function for checkLockedAddrs(): we really want to + // inline a quick check for an empty locked addr list (hopefully + // the common case), and do the full list search (if necessary) in + // this out-of-line function + bool checkLockedAddrList(Request *req); + + // Record the address of a load-locked operation so that we can + // clear the execution context's lock flag if a matching store is + // performed + void trackLoadLocked(Request *req); + + // Compare a store address with any locked addresses so we can + // clear the lock flag appropriately. Return value set to 'false' + // if store operation should be suppressed (because it was a + // conditional store and the address was no longer locked by the + // requesting execution context), 'true' otherwise. Note that + // this method must be called on *all* stores since even + // non-conditional stores must clear any matching lock addresses. + bool writeOK(Request *req) { + if (lockedAddrList.empty()) { + // no locked addrs: nothing to check, store_conditional fails + bool isLocked = req->isLocked(); + if (isLocked) { + req->setScResult(0); + } + return !isLocked; // only do write if not an sc + } else { + // iterate over list... + return checkLockedAddrList(req); + } + } + uint8_t *pmemAddr; MemoryPort *port; int pagePtr; |