From 3a2d2223e1debf932a0cec3244e4ce63e5d748af Mon Sep 17 00:00:00 2001 From: Joel Hestness Date: Sun, 6 Feb 2011 22:14:18 -0800 Subject: [PATCH] x86: Timing support for pagetable walker Move page table walker state to its own object type, and make the walker instantiate state for each outstanding walk. By storing the states in a queue, the walker is able to handle multiple outstanding timing requests. Note that functional walks use separate state elements. --- src/arch/x86/pagetable_walker.cc | 504 ++++++++++++++++++++----------- src/arch/x86/pagetable_walker.hh | 183 +++++------ src/arch/x86/tlb.cc | 6 + src/arch/x86/tlb.hh | 2 + 4 files changed, 439 insertions(+), 256 deletions(-) diff --git a/src/arch/x86/pagetable_walker.cc b/src/arch/x86/pagetable_walker.cc index cf82727a9..7c386dd02 100644 --- a/src/arch/x86/pagetable_walker.cc +++ b/src/arch/x86/pagetable_walker.cc @@ -40,6 +40,7 @@ #include "arch/x86/pagetable.hh" #include "arch/x86/pagetable_walker.hh" #include "arch/x86/tlb.hh" +#include "arch/x86/vtophys.hh" #include "base/bitfield.hh" #include "cpu/thread_context.hh" #include "cpu/base.hh" @@ -67,12 +68,209 @@ BitUnion64(PageTableEntry) EndBitUnion(PageTableEntry) Fault -Walker::doNext(PacketPtr &write) +Walker::start(ThreadContext * _tc, BaseTLB::Translation *_translation, + RequestPtr _req, BaseTLB::Mode _mode) +{ + // TODO: in timing mode, instead of blocking when there are other + // outstanding requests, see if this request can be coalesced with + // another one (i.e. either coalesce or start walk) + WalkerState * newState = new WalkerState(this, _translation, _req); + newState->initState(_tc, _mode, sys->getMemoryMode() == Enums::timing); + if (currStates.size()) { + assert(newState->isTiming()); + DPRINTF(PageTableWalker, "Walks in progress: %d\n", currStates.size()); + currStates.push_back(newState); + return NoFault; + } else { + currStates.push_back(newState); + Fault fault = newState->startWalk(); + if (!newState->isTiming()) { + currStates.pop_front(); + delete newState; + } + return fault; + } +} + +Fault +Walker::startFunctional(ThreadContext * _tc, Addr &addr, Addr &pageSize, + BaseTLB::Mode _mode) +{ + funcState.initState(_tc, _mode); + return funcState.startFunctional(addr, pageSize); +} + +bool +Walker::WalkerPort::recvTiming(PacketPtr pkt) +{ + return walker->recvTiming(pkt); +} + +bool +Walker::recvTiming(PacketPtr pkt) +{ + if (pkt->isResponse() || pkt->wasNacked()) { + WalkerSenderState * senderState = + dynamic_cast(pkt->senderState); + pkt->senderState = senderState->saved; + WalkerState * senderWalk = senderState->senderWalk; + bool walkComplete = senderWalk->recvPacket(pkt); + delete senderState; + if (walkComplete) { + std::list::iterator iter; + for (iter = currStates.begin(); iter != currStates.end(); iter++) { + WalkerState * walkerState = *(iter); + if (walkerState == senderWalk) { + iter = currStates.erase(iter); + break; + } + } + delete senderWalk; + // Since we block requests when another is outstanding, we + // need to check if there is a waiting request to be serviced + if (currStates.size()) { + WalkerState * newState = currStates.front(); + if (!newState->wasStarted()) + newState->startWalk(); + } + } + } else { + DPRINTF(PageTableWalker, "Received strange packet\n"); + } + return true; +} + +Tick +Walker::WalkerPort::recvAtomic(PacketPtr pkt) +{ + return 0; +} + +void +Walker::WalkerPort::recvFunctional(PacketPtr pkt) +{ + return; +} + +void +Walker::WalkerPort::recvStatusChange(Status status) +{ + if (status == RangeChange) { + if (!snoopRangeSent) { + snoopRangeSent = true; + sendStatusChange(Port::RangeChange); + } + return; + } + + panic("Unexpected recvStatusChange.\n"); +} + +void +Walker::WalkerPort::recvRetry() +{ + walker->recvRetry(); +} + +void +Walker::recvRetry() +{ + std::list::iterator iter; + for (iter = currStates.begin(); iter != currStates.end(); iter++) { + WalkerState * walkerState = *(iter); + if (walkerState->isRetrying()) { + walkerState->retry(); + } + } +} + +bool Walker::sendTiming(WalkerState* sendingState, PacketPtr pkt) +{ + pkt->senderState = new WalkerSenderState(sendingState, pkt->senderState); + return port.sendTiming(pkt); +} + +Port * +Walker::getPort(const std::string &if_name, int idx) +{ + if (if_name == "port") + return &port; + else + panic("No page table walker port named %s!\n", if_name); +} + +void +Walker::WalkerState::initState(ThreadContext * _tc, + BaseTLB::Mode _mode, bool _isTiming) +{ + assert(state == Ready); + started = false; + tc = _tc; + mode = _mode; + timing = _isTiming; +} + +Fault +Walker::WalkerState::startWalk() +{ + Fault fault = NoFault; + assert(started == false); + started = true; + setupWalk(req->getVaddr()); + if (timing) { + nextState = state; + state = Waiting; + timingFault = NoFault; + sendPackets(); + } else { + do { + walker->port.sendAtomic(read); + PacketPtr write = NULL; + fault = stepWalk(write); + assert(fault == NoFault || read == NULL); + state = nextState; + nextState = Ready; + if (write) + walker->port.sendAtomic(write); + } while(read); + state = Ready; + nextState = Waiting; + } + return fault; +} + +Fault +Walker::WalkerState::startFunctional(Addr &addr, Addr &pageSize) +{ + Fault fault = NoFault; + assert(started == false); + started = true; + setupWalk(addr); + + do { + walker->port.sendFunctional(read); + // On a functional access (page table lookup), writes should + // not happen so this pointer is ignored after stepWalk + PacketPtr write = NULL; + fault = stepWalk(write); + assert(fault == NoFault || read == NULL); + state = nextState; + nextState = Ready; + } while(read); + pageSize = entry.size; + addr = entry.paddr; + + return fault; +} + +Fault +Walker::WalkerState::stepWalk(PacketPtr &write) { assert(state != Ready && state != Waiting); + Fault fault = NoFault; write = NULL; PageTableEntry pte; - if (size == 8) + if (dataSize == 8) pte = read->get(); else pte = read->get(); @@ -80,19 +278,22 @@ Walker::doNext(PacketPtr &write) bool uncacheable = pte.pcd; Addr nextRead = 0; bool doWrite = false; + bool doTLBInsert = false; + bool doEndWalk = false; bool badNX = pte.nx && mode == BaseTLB::Execute && enableNX; switch(state) { case LongPML4: DPRINTF(PageTableWalker, "Got long mode PML4 entry %#016x.\n", (uint64_t)pte); - nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.longl3 * size; + nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.longl3 * dataSize; doWrite = !pte.a; pte.a = 1; entry.writable = pte.w; entry.user = pte.u; if (badNX || !pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } entry.noExec = pte.nx; nextState = LongPDP; @@ -100,14 +301,15 @@ Walker::doNext(PacketPtr &write) case LongPDP: DPRINTF(PageTableWalker, "Got long mode PDP entry %#016x.\n", (uint64_t)pte); - nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.longl2 * size; + nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.longl2 * dataSize; doWrite = !pte.a; pte.a = 1; entry.writable = entry.writable && pte.w; entry.user = entry.user && pte.u; if (badNX || !pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } nextState = LongPD; break; @@ -119,14 +321,15 @@ Walker::doNext(PacketPtr &write) entry.writable = entry.writable && pte.w; entry.user = entry.user && pte.u; if (badNX || !pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } if (!pte.ps) { // 4 KB page entry.size = 4 * (1 << 10); nextRead = - ((uint64_t)pte & (mask(40) << 12)) + vaddr.longl1 * size; + ((uint64_t)pte & (mask(40) << 12)) + vaddr.longl1 * dataSize; nextState = LongPTE; break; } else { @@ -137,9 +340,9 @@ Walker::doNext(PacketPtr &write) entry.global = pte.g; entry.patBit = bits(pte, 12); entry.vaddr = entry.vaddr & ~((2 * (1 << 20)) - 1); - tlb->insert(entry.vaddr, entry); - stop(); - return NoFault; + doTLBInsert = true; + doEndWalk = true; + break; } case LongPTE: DPRINTF(PageTableWalker, @@ -149,24 +352,26 @@ Walker::doNext(PacketPtr &write) entry.writable = entry.writable && pte.w; entry.user = entry.user && pte.u; if (badNX || !pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } entry.paddr = (uint64_t)pte & (mask(40) << 12); entry.uncacheable = uncacheable; entry.global = pte.g; entry.patBit = bits(pte, 12); entry.vaddr = entry.vaddr & ~((4 * (1 << 10)) - 1); - tlb->insert(entry.vaddr, entry); - stop(); - return NoFault; + doTLBInsert = true; + doEndWalk = true; + break; case PAEPDP: DPRINTF(PageTableWalker, "Got legacy mode PAE PDP entry %#08x.\n", (uint32_t)pte); - nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.pael2 * size; + nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.pael2 * dataSize; if (!pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } nextState = PAEPD; break; @@ -178,13 +383,14 @@ Walker::doNext(PacketPtr &write) entry.writable = pte.w; entry.user = pte.u; if (badNX || !pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } if (!pte.ps) { // 4 KB page entry.size = 4 * (1 << 10); - nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.pael1 * size; + nextRead = ((uint64_t)pte & (mask(40) << 12)) + vaddr.pael1 * dataSize; nextState = PAEPTE; break; } else { @@ -195,9 +401,9 @@ Walker::doNext(PacketPtr &write) entry.global = pte.g; entry.patBit = bits(pte, 12); entry.vaddr = entry.vaddr & ~((2 * (1 << 20)) - 1); - tlb->insert(entry.vaddr, entry); - stop(); - return NoFault; + doTLBInsert = true; + doEndWalk = true; + break; } case PAEPTE: DPRINTF(PageTableWalker, @@ -207,17 +413,18 @@ Walker::doNext(PacketPtr &write) entry.writable = entry.writable && pte.w; entry.user = entry.user && pte.u; if (badNX || !pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } entry.paddr = (uint64_t)pte & (mask(40) << 12); entry.uncacheable = uncacheable; entry.global = pte.g; entry.patBit = bits(pte, 7); entry.vaddr = entry.vaddr & ~((4 * (1 << 10)) - 1); - tlb->insert(entry.vaddr, entry); - stop(); - return NoFault; + doTLBInsert = true; + doEndWalk = true; + break; case PSEPD: DPRINTF(PageTableWalker, "Got legacy mode PSE PD entry %#08x.\n", (uint32_t)pte); @@ -226,14 +433,15 @@ Walker::doNext(PacketPtr &write) entry.writable = pte.w; entry.user = pte.u; if (!pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } if (!pte.ps) { // 4 KB page entry.size = 4 * (1 << 10); nextRead = - ((uint64_t)pte & (mask(20) << 12)) + vaddr.norml2 * size; + ((uint64_t)pte & (mask(20) << 12)) + vaddr.norml2 * dataSize; nextState = PTE; break; } else { @@ -244,9 +452,9 @@ Walker::doNext(PacketPtr &write) entry.global = pte.g; entry.patBit = bits(pte, 12); entry.vaddr = entry.vaddr & ~((4 * (1 << 20)) - 1); - tlb->insert(entry.vaddr, entry); - stop(); - return NoFault; + doTLBInsert = true; + doEndWalk = true; + break; } case PD: DPRINTF(PageTableWalker, @@ -256,12 +464,13 @@ Walker::doNext(PacketPtr &write) entry.writable = pte.w; entry.user = pte.u; if (!pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } // 4 KB page entry.size = 4 * (1 << 10); - nextRead = ((uint64_t)pte & (mask(20) << 12)) + vaddr.norml2 * size; + nextRead = ((uint64_t)pte & (mask(20) << 12)) + vaddr.norml2 * dataSize; nextState = PTE; break; case PTE: @@ -272,66 +481,73 @@ Walker::doNext(PacketPtr &write) entry.writable = pte.w; entry.user = pte.u; if (!pte.p) { - stop(); - return pageFault(pte.p); + doEndWalk = true; + fault = pageFault(pte.p); + break; } entry.paddr = (uint64_t)pte & (mask(20) << 12); entry.uncacheable = uncacheable; entry.global = pte.g; entry.patBit = bits(pte, 7); entry.vaddr = entry.vaddr & ~((4 * (1 << 10)) - 1); - tlb->insert(entry.vaddr, entry); - stop(); - return NoFault; + doTLBInsert = true; + doEndWalk = true; + break; default: panic("Unknown page table walker state %d!\n"); } - PacketPtr oldRead = read; - //If we didn't return, we're setting up another read. - Request::Flags flags = oldRead->req->getFlags(); - flags.set(Request::UNCACHEABLE, uncacheable); - RequestPtr request = - new Request(nextRead, oldRead->getSize(), flags); - read = new Packet(request, MemCmd::ReadExReq, Packet::Broadcast); - read->allocate(); - //If we need to write, adjust the read packet to write the modified value - //back to memory. - if (doWrite) { - write = oldRead; - write->set(pte); - write->cmd = MemCmd::WriteReq; - write->setDest(Packet::Broadcast); + if (doEndWalk) { + if (doTLBInsert) + if (!functional) + walker->tlb->insert(entry.vaddr, entry); + endWalk(); } else { - write = NULL; - delete oldRead->req; - delete oldRead; + PacketPtr oldRead = read; + //If we didn't return, we're setting up another read. + Request::Flags flags = oldRead->req->getFlags(); + flags.set(Request::UNCACHEABLE, uncacheable); + RequestPtr request = + new Request(nextRead, oldRead->getSize(), flags); + read = new Packet(request, MemCmd::ReadExReq, Packet::Broadcast); + read->allocate(); + // If we need to write, adjust the read packet to write the modified + // value back to memory. + if (doWrite) { + write = oldRead; + write->set(pte); + write->cmd = MemCmd::WriteReq; + write->setDest(Packet::Broadcast); + } else { + write = NULL; + delete oldRead->req; + delete oldRead; + } } - return NoFault; + return fault; } -Fault -Walker::start(ThreadContext * _tc, BaseTLB::Translation *_translation, - RequestPtr _req, BaseTLB::Mode _mode) +void +Walker::WalkerState::endWalk() { - assert(state == Ready); - tc = _tc; - req = _req; - Addr vaddr = req->getVaddr(); - mode = _mode; - translation = _translation; + nextState = Ready; + delete read->req; + delete read; + read = NULL; +} +void +Walker::WalkerState::setupWalk(Addr vaddr) +{ VAddr addr = vaddr; - - //Figure out what we're doing. CR3 cr3 = tc->readMiscRegNoEffect(MISCREG_CR3); - Addr top = 0; // Check if we're in long mode or not Efer efer = tc->readMiscRegNoEffect(MISCREG_EFER); - size = 8; + dataSize = 8; + Addr topAddr; if (efer.lma) { // Do long mode. state = LongPML4; - top = (cr3.longPdtb << 12) + addr.longl4 * size; + topAddr = (cr3.longPdtb << 12) + addr.longl4 * dataSize; enableNX = efer.nxe; } else { // We're in some flavor of legacy mode. @@ -339,11 +555,11 @@ Walker::start(ThreadContext * _tc, BaseTLB::Translation *_translation, if (cr4.pae) { // Do legacy PAE. state = PAEPDP; - top = (cr3.paePdtb << 5) + addr.pael3 * size; + topAddr = (cr3.paePdtb << 5) + addr.pael3 * dataSize; enableNX = efer.nxe; } else { - size = 4; - top = (cr3.pdtb << 12) + addr.norml2 * size; + dataSize = 4; + topAddr = (cr3.pdtb << 12) + addr.norml2 * dataSize; if (cr4.pse) { // Do legacy PSE. state = PSEPD; @@ -361,44 +577,13 @@ Walker::start(ThreadContext * _tc, BaseTLB::Translation *_translation, Request::Flags flags = Request::PHYSICAL; if (cr3.pcd) flags.set(Request::UNCACHEABLE); - RequestPtr request = new Request(top, size, flags); + RequestPtr request = new Request(topAddr, dataSize, flags); read = new Packet(request, MemCmd::ReadExReq, Packet::Broadcast); read->allocate(); - Enums::MemoryMode memMode = sys->getMemoryMode(); - if (memMode == Enums::timing) { - nextState = state; - state = Waiting; - timingFault = NoFault; - sendPackets(); - } else if (memMode == Enums::atomic) { - Fault fault; - do { - port.sendAtomic(read); - PacketPtr write = NULL; - fault = doNext(write); - assert(fault == NoFault || read == NULL); - state = nextState; - nextState = Ready; - if (write) - port.sendAtomic(write); - } while(read); - state = Ready; - nextState = Waiting; - return fault; - } else { - panic("Unrecognized memory system mode.\n"); - } - return NoFault; -} - -bool -Walker::WalkerPort::recvTiming(PacketPtr pkt) -{ - return walker->recvTiming(pkt); } bool -Walker::recvTiming(PacketPtr pkt) +Walker::WalkerState::recvPacket(PacketPtr pkt) { if (pkt->isResponse() && !pkt->wasNacked()) { assert(inflight); @@ -410,7 +595,7 @@ Walker::recvTiming(PacketPtr pkt) nextState = Ready; PacketPtr write = NULL; read = pkt; - timingFault = doNext(write); + timingFault = stepWalk(write); state = Waiting; assert(timingFault == NoFault || read == NULL); if (write) { @@ -432,7 +617,7 @@ Walker::recvTiming(PacketPtr pkt) * well. */ bool delayedResponse; - Fault fault = tlb->translate(req, tc, NULL, mode, + Fault fault = walker->tlb->translate(req, tc, NULL, mode, delayedResponse, true); assert(!delayedResponse); // Let the CPU continue. @@ -441,10 +626,12 @@ Walker::recvTiming(PacketPtr pkt) // There was a fault during the walk. Let the CPU know. translation->finish(timingFault, req, tc, mode); } + return true; } } else if (pkt->wasNacked()) { + DPRINTF(PageTableWalker, "Request was nacked. Entering retry state\n"); pkt->reinitNacked(); - if (!port.sendTiming(pkt)) { + if (!walker->sendTiming(this, pkt)) { inflight--; retrying = true; if (pkt->isWrite()) { @@ -455,50 +642,11 @@ Walker::recvTiming(PacketPtr pkt) } } } - return true; -} - -Tick -Walker::WalkerPort::recvAtomic(PacketPtr pkt) -{ - return 0; -} - -void -Walker::WalkerPort::recvFunctional(PacketPtr pkt) -{ - return; -} - -void -Walker::WalkerPort::recvStatusChange(Status status) -{ - if (status == RangeChange) { - if (!snoopRangeSent) { - snoopRangeSent = true; - sendStatusChange(Port::RangeChange); - } - return; - } - - panic("Unexpected recvStatusChange.\n"); -} - -void -Walker::WalkerPort::recvRetry() -{ - walker->recvRetry(); + return false; } void -Walker::recvRetry() -{ - retrying = false; - sendPackets(); -} - -void -Walker::sendPackets() +Walker::WalkerState::sendPackets() { //If we're already waiting for the port to become available, just return. if (retrying) @@ -509,7 +657,7 @@ Walker::sendPackets() PacketPtr pkt = read; read = NULL; inflight++; - if (!port.sendTiming(pkt)) { + if (!walker->sendTiming(this, pkt)) { retrying = true; read = pkt; inflight--; @@ -521,7 +669,7 @@ Walker::sendPackets() PacketPtr write = writes.back(); writes.pop_back(); inflight++; - if (!port.sendTiming(write)) { + if (!walker->sendTiming(this, write)) { retrying = true; writes.push_back(write); inflight--; @@ -530,17 +678,33 @@ Walker::sendPackets() } } -Port * -Walker::getPort(const std::string &if_name, int idx) +bool +Walker::WalkerState::isRetrying() { - if (if_name == "port") - return &port; - else - panic("No page table walker port named %s!\n", if_name); + return retrying; +} + +bool +Walker::WalkerState::isTiming() +{ + return timing; +} + +bool +Walker::WalkerState::wasStarted() +{ + return started; +} + +void +Walker::WalkerState::retry() +{ + retrying = false; + sendPackets(); } Fault -Walker::pageFault(bool present) +Walker::WalkerState::pageFault(bool present) { DPRINTF(PageTableWalker, "Raising page fault.\n"); HandyM5Reg m5reg = tc->readMiscRegNoEffect(MISCREG_M5_REG); @@ -549,7 +713,7 @@ Walker::pageFault(bool present) return new PageFault(entry.vaddr, present, mode, m5reg.cpl == 3, false); } -} +/* end namespace X86ISA */ } X86ISA::Walker * X86PagetableWalkerParams::create() diff --git a/src/arch/x86/pagetable_walker.hh b/src/arch/x86/pagetable_walker.hh index 68f85be93..007c577ae 100644 --- a/src/arch/x86/pagetable_walker.hh +++ b/src/arch/x86/pagetable_walker.hh @@ -45,6 +45,7 @@ #include "arch/x86/pagetable.hh" #include "arch/x86/tlb.hh" #include "base/types.hh" +#include "base/fast_alloc.hh" #include "mem/mem_object.hh" #include "mem/packet.hh" #include "params/X86PagetableWalker.hh" @@ -56,70 +57,8 @@ namespace X86ISA { class Walker : public MemObject { - public: - enum State { - Ready, - Waiting, - // Long mode - LongPML4, LongPDP, LongPD, LongPTE, - // PAE legacy mode - PAEPDP, PAEPD, PAEPTE, - // Non PAE legacy mode with and without PSE - PSEPD, PD, PTE - }; - - // Act on the current state and determine what to do next. The global - // read should be the packet that just came back from a read and write - // should be NULL. When the function returns, read is either NULL - // if the machine is finished, or points to a packet to initiate - // the next read. If any write is required to update an "accessed" - // bit, write will point to a packet to do the write. Otherwise it - // will be NULL. The return value is whatever fault was incurred - // during this stage of the lookup. - Fault doNext(PacketPtr &write); - - // Kick off the state machine. - Fault start(ThreadContext * _tc, BaseTLB::Translation *translation, - RequestPtr req, BaseTLB::Mode mode); - // Clean up after the state machine. - void - stop() - { - nextState = Ready; - delete read->req; - delete read; - read = NULL; - } - protected: - - /* - * State having to do with sending packets. - */ - PacketPtr read; - std::vector writes; - - // How many memory operations are in flight. - unsigned inflight; - - bool retrying; - - /* - * The fault, if any, that's waiting to be delivered in timing mode. - */ - Fault timingFault; - - /* - * Functions for dealing with packets. - */ - bool recvTiming(PacketPtr pkt); - void recvRetry(); - - void sendPackets(); - - /* - * Port for accessing memory - */ + // Port for accessing memory class WalkerPort : public Port { public: @@ -146,31 +85,106 @@ namespace X86ISA } }; + friend class WalkerPort; + WalkerPort port; Port *getPort(const std::string &if_name, int idx = -1); - friend class WalkerPort; + // State to track each walk of the page table + class WalkerState : public FastAlloc + { + private: + enum State { + Ready, + Waiting, + // Long mode + LongPML4, LongPDP, LongPD, LongPTE, + // PAE legacy mode + PAEPDP, PAEPD, PAEPTE, + // Non PAE legacy mode with and without PSE + PSEPD, PD, PTE + }; - WalkerPort port; + protected: + Walker * walker; + ThreadContext *tc; + RequestPtr req; + State state; + State nextState; + int dataSize; + bool enableNX; + unsigned inflight; + TlbEntry entry; + PacketPtr read; + std::vector writes; + Fault timingFault; + TLB::Translation * translation; + BaseTLB::Mode mode; + bool functional; + bool timing; + bool retrying; + bool started; + + public: + WalkerState(Walker * _walker, BaseTLB::Translation *_translation, + RequestPtr _req, bool _isFunctional = false) : + walker(_walker), req(_req), state(Ready), + nextState(Ready), inflight(0), + translation(_translation), + functional(_isFunctional), timing(false), + retrying(false), started(false) + { + } + void initState(ThreadContext * _tc, BaseTLB::Mode _mode, + bool _isTiming = false); + Fault startWalk(); + Fault startFunctional(Addr &addr, Addr &pageSize); + bool recvPacket(PacketPtr pkt); + bool isRetrying(); + bool wasStarted(); + bool isTiming(); + void retry(); + std::string name() const {return walker->name();} + + private: + void setupWalk(Addr vaddr); + Fault stepWalk(PacketPtr &write); + void sendPackets(); + void endWalk(); + Fault pageFault(bool present); + }; + + friend class WalkerState; + // State for timing and atomic accesses (need multiple per walker in + // the case of multiple outstanding requests in timing mode) + std::list currStates; + // State for functional accesses (only need one of these per walker) + WalkerState funcState; + + struct WalkerSenderState : public Packet::SenderState + { + WalkerState * senderWalk; + Packet::SenderState * saved; + WalkerSenderState(WalkerState * _senderWalk, + Packet::SenderState * _saved) : + senderWalk(_senderWalk), saved(_saved) {} + }; + public: + // Kick off the state machine. + Fault start(ThreadContext * _tc, BaseTLB::Translation *translation, + RequestPtr req, BaseTLB::Mode mode); + Fault startFunctional(ThreadContext * _tc, Addr &addr, + Addr &pageSize, BaseTLB::Mode mode); + + protected: // The TLB we're supposed to load. TLB * tlb; System * sys; - BaseTLB::Translation * translation; - - /* - * State machine state. - */ - ThreadContext * tc; - RequestPtr req; - State state; - State nextState; - int size; - bool enableNX; - BaseTLB::Mode mode; - bool user; - TlbEntry entry; - - Fault pageFault(bool present); + + // Functions for dealing with packets. + bool recvTiming(PacketPtr pkt); + void recvRetry(); + bool sendTiming(WalkerState * sendingState, PacketPtr pkt); public: @@ -182,11 +196,8 @@ namespace X86ISA typedef X86PagetableWalkerParams Params; Walker(const Params *params) : - MemObject(params), - read(NULL), inflight(0), retrying(false), - port(name() + ".port", this), - tlb(NULL), sys(params->system), - tc(NULL), state(Ready), nextState(Ready) + MemObject(params), port(name() + ".port", this), + funcState(this, NULL, NULL, true), tlb(NULL), sys(params->system) { } }; diff --git a/src/arch/x86/tlb.cc b/src/arch/x86/tlb.cc index 7fa2e172c..a02c5e6a3 100644 --- a/src/arch/x86/tlb.cc +++ b/src/arch/x86/tlb.cc @@ -725,6 +725,12 @@ TLB::doMmuRegWrite(ThreadContext *tc, Packet *pkt) return tc->getCpuPtr()->ticks(1); } +Walker * +TLB::getWalker() +{ + return walker; +} + #endif void diff --git a/src/arch/x86/tlb.hh b/src/arch/x86/tlb.hh index 0e96b26b8..965d331ba 100644 --- a/src/arch/x86/tlb.hh +++ b/src/arch/x86/tlb.hh @@ -89,6 +89,8 @@ namespace X86ISA protected: Walker * walker; + public: + Walker *getWalker(); #endif public: -- 2.30.2