Merge zizzer:/z/m5/Bitkeeper/newmem

into  zazzer.eecs.umich.edu:/z/rdreslin/m5bk/newmem

--HG--
extra : convert_revision : 6eefb4a3ee472f2f2c86ed823c70fc9e5625818f

8 files changed, 2477 insertions, 0 deletions

diff --git a/src/mem/cache/miss/blocking_buffer.cc b/src/mem/cache/miss/blocking_buffer.cc
new file mode 100644
index 000000000..d745cb8c6
--- /dev/null
+++ b/src/mem/cache/miss/blocking_buffer.cc
@@ -0,0 +1,246 @@
+/*
+ * Copyright (c) 2003-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ */
+
+/**
+ * @file
+ * Definitions of a simple buffer for a blocking cache.
+ */
+
+#include "cpu/smt.hh" //for maxThreadsPerCPU
+#include "mem/cache/base_cache.hh"
+#include "mem/cache/miss/blocking_buffer.hh"
+#include "mem/cache/prefetch/base_prefetcher.hh"
+#include "sim/eventq.hh" // for Event declaration.
+#include "mem/request.hh"
+
+using namespace TheISA;
+
+/**
+ * @todo Move writebacks into shared BaseBuffer class.
+ */
+void
+BlockingBuffer::regStats(const std::string &name)
+{
+    using namespace Stats;
+    writebacks
+        .init(maxThreadsPerCPU)
+        .name(name + ".writebacks")
+        .desc("number of writebacks")
+        .flags(total)
+        ;
+}
+
+void
+BlockingBuffer::setCache(BaseCache *_cache)
+{
+    cache = _cache;
+    blkSize = cache->getBlockSize();
+}
+
+void
+BlockingBuffer::setPrefetcher(BasePrefetcher *_prefetcher)
+{
+    prefetcher = _prefetcher;
+}
+void
+BlockingBuffer::handleMiss(Packet * &pkt, int blk_size, Tick time)
+{
+    Addr blk_addr = pkt->getAddr() & ~(Addr)(blk_size - 1);
+    if (pkt->isWrite() && (pkt->req->isUncacheable() || !writeAllocate ||
+                               !pkt->needsResponse())) {
+        if (!pkt->needsResponse()) {
+            wb.allocateAsBuffer(pkt);
+        } else {
+            wb.allocate(pkt->cmd, blk_addr, pkt->req->getAsid(), blk_size, pkt);
+        }
+
+        memcpy(wb.pkt->getPtr<uint8_t>(), pkt->getPtr<uint8_t>(), blk_size);
+
+        cache->setBlocked(Blocked_NoWBBuffers);
+        cache->setMasterRequest(Request_WB, time);
+        return;
+    }
+
+    if (!pkt->needsResponse()) {
+        miss.allocateAsBuffer(pkt);
+    } else {
+        miss.allocate(pkt->cmd, blk_addr, pkt->req->getAsid(), blk_size, pkt);
+    }
+    if (!pkt->req->isUncacheable()) {
+        miss.pkt->flags |= CACHE_LINE_FILL;
+    }
+    cache->setBlocked(Blocked_NoMSHRs);
+    cache->setMasterRequest(Request_MSHR, time);
+}
+
+Packet *
+BlockingBuffer::getPacket()
+{
+    if (miss.pkt && !miss.inService) {
+        return miss.pkt;
+    }
+    return wb.pkt;
+}
+
+void
+BlockingBuffer::setBusCmd(Packet * &pkt, Packet::Command cmd)
+{
+    MSHR *mshr = (MSHR*) pkt->senderState;
+    mshr->originalCmd = pkt->cmd;
+    if (pkt->isCacheFill())
+        pkt->cmdOverride(cmd);
+}
+
+void
+BlockingBuffer::restoreOrigCmd(Packet * &pkt)
+{
+    pkt->cmdOverride(((MSHR*)(pkt->senderState))->originalCmd);
+}
+
+void
+BlockingBuffer::markInService(Packet * &pkt)
+{
+    if (!pkt->isCacheFill() && pkt->isWrite()) {
+        // Forwarding a write/ writeback, don't need to change
+        // the command
+        assert((MSHR*)pkt->senderState == &wb);
+        cache->clearMasterRequest(Request_WB);
+        if (!pkt->needsResponse()) {
+            assert(wb.getNumTargets() == 0);
+            wb.deallocate();
+            cache->clearBlocked(Blocked_NoWBBuffers);
+        } else {
+            wb.inService = true;
+        }
+    } else {
+        assert((MSHR*)pkt->senderState == &miss);
+        cache->clearMasterRequest(Request_MSHR);
+        if (!pkt->needsResponse()) {
+            assert(miss.getNumTargets() == 0);
+            miss.deallocate();
+            cache->clearBlocked(Blocked_NoMSHRs);
+        } else {
+            //mark in service
+            miss.inService = true;
+        }
+    }
+}
+
+void
+BlockingBuffer::handleResponse(Packet * &pkt, Tick time)
+{
+    if (pkt->isCacheFill()) {
+        // targets were handled in the cache tags
+        assert((MSHR*)pkt->senderState == &miss);
+        miss.deallocate();
+        cache->clearBlocked(Blocked_NoMSHRs);
+    } else {
+        if (((MSHR*)(pkt->senderState))->hasTargets()) {
+            // Should only have 1 target if we had any
+            assert(((MSHR*)(pkt->senderState))->getNumTargets() == 1);
+            Packet * target = ((MSHR*)(pkt->senderState))->getTarget();
+            ((MSHR*)(pkt->senderState))->popTarget();
+            if (pkt->isRead()) {
+                memcpy(target->getPtr<uint8_t>(), pkt->getPtr<uint8_t>(), target->getSize());
+            }
+            cache->respond(target, time);
+            assert(!((MSHR*)(pkt->senderState))->hasTargets());
+        }
+
+        if (pkt->isWrite()) {
+            assert(((MSHR*)(pkt->senderState)) == &wb);
+            wb.deallocate();
+            cache->clearBlocked(Blocked_NoWBBuffers);
+        } else {
+            miss.deallocate();
+            cache->clearBlocked(Blocked_NoMSHRs);
+        }
+    }
+}
+
+void
+BlockingBuffer::squash(int threadNum)
+{
+    if (miss.threadNum == threadNum) {
+        Packet * target = miss.getTarget();
+        miss.popTarget();
+        assert(target->req->getThreadNum() == threadNum);
+        target = NULL;
+        assert(!miss.hasTargets());
+        miss.ntargets=0;
+        if (!miss.inService) {
+            miss.deallocate();
+            cache->clearBlocked(Blocked_NoMSHRs);
+            cache->clearMasterRequest(Request_MSHR);
+        }
+    }
+}
+
+void
+BlockingBuffer::doWriteback(Addr addr, int asid,
+                            int size, uint8_t *data, bool compressed)
+{
+    // Generate request
+    Request * req = new Request(addr, size, 0);
+    Packet * pkt = new Packet(req, Packet::Writeback, -1);
+    uint8_t *new_data = new uint8_t[size];
+    pkt->dataDynamicArray<uint8_t>(new_data);
+    if (data) {
+        memcpy(pkt->getPtr<uint8_t>(), data, size);
+    }
+
+    if (compressed) {
+        pkt->flags |= COMPRESSED;
+    }
+
+    ///All writebacks charged to same thread @todo figure this out
+    writebacks[pkt->req->getThreadNum()]++;
+
+    wb.allocateAsBuffer(pkt);
+    cache->setMasterRequest(Request_WB, curTick);
+    cache->setBlocked(Blocked_NoWBBuffers);
+}
+
+
+
+void
+BlockingBuffer::doWriteback(Packet * &pkt)
+{
+    writebacks[pkt->req->getThreadNum()]++;
+
+    wb.allocateAsBuffer(pkt);
+
+    // Since allocate as buffer copies the request,
+    // need to copy data here.
+        memcpy(wb.pkt->getPtr<uint8_t>(), pkt->getPtr<uint8_t>(), pkt->getSize());
+
+    cache->setBlocked(Blocked_NoWBBuffers);
+    cache->setMasterRequest(Request_WB, curTick);
+}
diff --git a/src/mem/cache/miss/blocking_buffer.hh b/src/mem/cache/miss/blocking_buffer.hh
new file mode 100644
index 000000000..39a06a377
--- /dev/null
+++ b/src/mem/cache/miss/blocking_buffer.hh
@@ -0,0 +1,256 @@
+/*
+ * Copyright (c) 2003-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ */
+
+/**
+ * @file
+ * Declaration of a simple buffer for a blocking cache.
+ */
+
+#ifndef __BLOCKING_BUFFER_HH__
+#define __BLOCKING_BUFFER_HH__
+
+#include <vector>
+
+#include "mem/cache/miss/mshr.hh"
+#include "base/statistics.hh"
+
+class BaseCache;
+class BasePrefetcher;
+
+/**
+ * Miss and writeback storage for a blocking cache.
+ */
+class BlockingBuffer
+{
+protected:
+    /** Miss storage. */
+    MSHR miss;
+    /** WB storage. */
+    MSHR wb;
+
+    //Params
+
+    /** Allocate on write misses. */
+    const bool writeAllocate;
+
+    /** Pointer to the parent cache. */
+    BaseCache* cache;
+
+    BasePrefetcher* prefetcher;
+
+    /** Block size of the parent cache. */
+    int blkSize;
+
+    // Statistics
+    /**
+     * @addtogroup CacheStatistics
+     * @{
+     */
+    /** Number of blocks written back per thread. */
+    Stats::Vector<> writebacks;
+
+    /**
+     * @}
+     */
+
+public:
+    /**
+     * Builds and initializes this buffer.
+     * @param write_allocate If true, treat write misses the same as reads.
+     */
+    BlockingBuffer(bool write_allocate)
+        : writeAllocate(write_allocate)
+    {
+    }
+
+    /**
+     * Register statistics for this object.
+     * @param name The name of the parent cache.
+     */
+    void regStats(const std::string &name);
+
+    /**
+     * Called by the parent cache to set the back pointer.
+     * @param _cache A pointer to the parent cache.
+     */
+    void setCache(BaseCache *_cache);
+
+    void setPrefetcher(BasePrefetcher *_prefetcher);
+
+    /**
+     * Handle a cache miss properly. Requests the bus and marks the cache as
+     * blocked.
+     * @param req The request that missed in the cache.
+     * @param blk_size The block size of the cache.
+     * @param time The time the miss is detected.
+     */
+    void handleMiss(Packet * &pkt, int blk_size, Tick time);
+
+    /**
+     * Fetch the block for the given address and buffer the given target.
+     * @param addr The address to fetch.
+     * @param asid The address space of the address.
+     * @param blk_size The block size of the cache.
+     * @param time The time the miss is detected.
+     * @param target The target for the fetch.
+     */
+    MSHR* fetchBlock(Addr addr, int asid, int blk_size, Tick time,
+                     Packet * &target)
+    {
+        fatal("Unimplemented");
+    }
+
+    /**
+     * Selects a outstanding request to service.
+     * @return The request to service, NULL if none found.
+     */
+    Packet * getPacket();
+
+    /**
+     * Set the command to the given bus command.
+     * @param req The request to update.
+     * @param cmd The bus command to use.
+     */
+    void setBusCmd(Packet * &pkt, Packet::Command cmd);
+
+    /**
+     * Restore the original command in case of a bus transmission error.
+     * @param req The request to reset.
+     */
+    void restoreOrigCmd(Packet * &pkt);
+
+    /**
+     * Marks a request as in service (sent on the bus). This can have side
+     * effect since storage for no response commands is deallocated once they
+     * are successfully sent.
+     * @param req The request that was sent on the bus.
+     */
+    void markInService(Packet * &pkt);
+
+    /**
+     * Frees the resources of the request and unblock the cache.
+     * @param req The request that has been satisfied.
+     * @param time The time when the request is satisfied.
+     */
+    void handleResponse(Packet * &pkt, Tick time);
+
+    /**
+     * Removes all outstanding requests for a given thread number. If a request
+     * has been sent to the bus, this function removes all of its targets.
+     * @param req->getThreadNum()ber The thread number of the requests to squash.
+     */
+    void squash(int threadNum);
+
+    /**
+     * Return the current number of outstanding misses.
+     * @return the number of outstanding misses.
+     */
+    int getMisses()
+    {
+        return miss.getNumTargets();
+    }
+
+    /**
+     * Searches for the supplied address in the miss "queue".
+     * @param addr The address to look for.
+     * @param asid The address space id.
+     * @return A pointer to miss if it matches.
+     */
+    MSHR* findMSHR(Addr addr, int asid)
+    {
+        if (miss.addr == addr && miss.pkt)
+            return &miss;
+        return NULL;
+    }
+
+    /**
+     * Searches for the supplied address in the write buffer.
+     * @param addr The address to look for.
+     * @param asid The address space id.
+     * @param writes List of pointers to the matching writes.
+     * @return True if there is a matching write.
+     */
+    bool findWrites(Addr addr, int asid, std::vector<MSHR*>& writes)
+    {
+        if (wb.addr == addr && wb.pkt) {
+            writes.push_back(&wb);
+            return true;
+        }
+        return false;
+    }
+
+
+
+    /**
+     * Perform a writeback of dirty data to the given address.
+     * @param addr The address to write to.
+     * @param asid The address space id.
+     * @param size The number of bytes to write.
+     * @param data The data to write, can be NULL.
+     * @param compressed True if the data is compressed.
+     */
+    void doWriteback(Addr addr, int asid,
+                     int size, uint8_t *data, bool compressed);
+
+    /**
+     * Perform a writeback request.
+     * @param req The writeback request.
+     */
+    void doWriteback(Packet * &pkt);
+
+    /**
+     * Returns true if there are outstanding requests.
+     * @return True if there are outstanding requests.
+     */
+    bool havePending()
+    {
+        return !miss.inService || !wb.inService;
+    }
+
+    /**
+     * Add a target to the given MSHR. This assumes it is in the miss queue.
+     * @param mshr The mshr to add a target to.
+     * @param req The target to add.
+     */
+    void addTarget(MSHR *mshr, Packet * &pkt)
+    {
+        fatal("Shouldn't call this on a blocking buffer.");
+    }
+
+    /**
+     * Dummy implmentation.
+     */
+    MSHR* allocateTargetList(Addr addr, int asid)
+    {
+        fatal("Unimplemented");
+    }
+};
+
+#endif // __BLOCKING_BUFFER_HH__
diff --git a/src/mem/cache/miss/miss_queue.cc b/src/mem/cache/miss/miss_queue.cc
new file mode 100644
index 000000000..34290351d
--- /dev/null
+++ b/src/mem/cache/miss/miss_queue.cc
@@ -0,0 +1,757 @@
+/*
+ * Copyright (c) 2003-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ *          Ron Dreslinski
+ */
+
+/**
+ * @file
+ * Miss and writeback queue definitions.
+ */
+
+#include "cpu/smt.hh" //for maxThreadsPerCPU
+#include "mem/cache/base_cache.hh"
+#include "mem/cache/miss/miss_queue.hh"
+#include "mem/cache/prefetch/base_prefetcher.hh"
+
+using namespace std;
+
+// simple constructor
+/**
+ * @todo Remove the +16 from the write buffer constructor once we handle
+ * stalling on writebacks do to compression writes.
+ */
+MissQueue::MissQueue(int numMSHRs, int numTargets, int write_buffers,
+                     bool write_allocate, bool prefetch_miss)
+    : mq(numMSHRs, 4), wb(write_buffers,numMSHRs+1000), numMSHR(numMSHRs),
+      numTarget(numTargets), writeBuffers(write_buffers),
+      writeAllocate(write_allocate), order(0), prefetchMiss(prefetch_miss)
+{
+    noTargetMSHR = NULL;
+}
+
+void
+MissQueue::regStats(const string &name)
+{
+    Request temp_req;
+    Packet::Command temp_cmd = Packet::ReadReq;
+    Packet temp_pkt(&temp_req, temp_cmd, 0);  //@todo FIx command strings so this isn't neccessary
+
+    using namespace Stats;
+
+    writebacks
+        .init(maxThreadsPerCPU)
+        .name(name + ".writebacks")
+        .desc("number of writebacks")
+        .flags(total)
+        ;
+
+    // MSHR hit statistics
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        mshr_hits[access_idx]
+            .init(maxThreadsPerCPU)
+            .name(name + "." + cstr + "_mshr_hits")
+            .desc("number of " + cstr + " MSHR hits")
+            .flags(total | nozero | nonan)
+            ;
+    }
+
+    demandMshrHits
+        .name(name + ".demand_mshr_hits")
+        .desc("number of demand (read+write) MSHR hits")
+        .flags(total)
+        ;
+    demandMshrHits = mshr_hits[Packet::ReadReq] + mshr_hits[Packet::WriteReq];
+
+    overallMshrHits
+        .name(name + ".overall_mshr_hits")
+        .desc("number of overall MSHR hits")
+        .flags(total)
+        ;
+    overallMshrHits = demandMshrHits + mshr_hits[Packet::SoftPFReq] +
+        mshr_hits[Packet::HardPFReq];
+
+    // MSHR miss statistics
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        mshr_misses[access_idx]
+            .init(maxThreadsPerCPU)
+            .name(name + "." + cstr + "_mshr_misses")
+            .desc("number of " + cstr + " MSHR misses")
+            .flags(total | nozero | nonan)
+            ;
+    }
+
+    demandMshrMisses
+        .name(name + ".demand_mshr_misses")
+        .desc("number of demand (read+write) MSHR misses")
+        .flags(total)
+        ;
+    demandMshrMisses = mshr_misses[Packet::ReadReq] + mshr_misses[Packet::WriteReq];
+
+    overallMshrMisses
+        .name(name + ".overall_mshr_misses")
+        .desc("number of overall MSHR misses")
+        .flags(total)
+        ;
+    overallMshrMisses = demandMshrMisses + mshr_misses[Packet::SoftPFReq] +
+        mshr_misses[Packet::HardPFReq];
+
+    // MSHR miss latency statistics
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        mshr_miss_latency[access_idx]
+            .init(maxThreadsPerCPU)
+            .name(name + "." + cstr + "_mshr_miss_latency")
+            .desc("number of " + cstr + " MSHR miss cycles")
+            .flags(total | nozero | nonan)
+            ;
+    }
+
+    demandMshrMissLatency
+        .name(name + ".demand_mshr_miss_latency")
+        .desc("number of demand (read+write) MSHR miss cycles")
+        .flags(total)
+        ;
+    demandMshrMissLatency = mshr_miss_latency[Packet::ReadReq]
+        + mshr_miss_latency[Packet::WriteReq];
+
+    overallMshrMissLatency
+        .name(name + ".overall_mshr_miss_latency")
+        .desc("number of overall MSHR miss cycles")
+        .flags(total)
+        ;
+    overallMshrMissLatency = demandMshrMissLatency +
+        mshr_miss_latency[Packet::SoftPFReq] + mshr_miss_latency[Packet::HardPFReq];
+
+    // MSHR uncacheable statistics
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        mshr_uncacheable[access_idx]
+            .init(maxThreadsPerCPU)
+            .name(name + "." + cstr + "_mshr_uncacheable")
+            .desc("number of " + cstr + " MSHR uncacheable")
+            .flags(total | nozero | nonan)
+            ;
+    }
+
+    overallMshrUncacheable
+        .name(name + ".overall_mshr_uncacheable_misses")
+        .desc("number of overall MSHR uncacheable misses")
+        .flags(total)
+        ;
+    overallMshrUncacheable = mshr_uncacheable[Packet::ReadReq]
+        + mshr_uncacheable[Packet::WriteReq] + mshr_uncacheable[Packet::SoftPFReq]
+        + mshr_uncacheable[Packet::HardPFReq];
+
+    // MSHR miss latency statistics
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        mshr_uncacheable_lat[access_idx]
+            .init(maxThreadsPerCPU)
+            .name(name + "." + cstr + "_mshr_uncacheable_latency")
+            .desc("number of " + cstr + " MSHR uncacheable cycles")
+            .flags(total | nozero | nonan)
+            ;
+    }
+
+    overallMshrUncacheableLatency
+        .name(name + ".overall_mshr_uncacheable_latency")
+        .desc("number of overall MSHR uncacheable cycles")
+        .flags(total)
+        ;
+    overallMshrUncacheableLatency = mshr_uncacheable_lat[Packet::ReadReq]
+        + mshr_uncacheable_lat[Packet::WriteReq]
+        + mshr_uncacheable_lat[Packet::SoftPFReq]
+        + mshr_uncacheable_lat[Packet::HardPFReq];
+
+#if 0
+    // MSHR access formulas
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        mshrAccesses[access_idx]
+            .name(name + "." + cstr + "_mshr_accesses")
+            .desc("number of " + cstr + " mshr accesses(hits+misses)")
+            .flags(total | nozero | nonan)
+            ;
+        mshrAccesses[access_idx] =
+            mshr_hits[access_idx] + mshr_misses[access_idx]
+            + mshr_uncacheable[access_idx];
+    }
+
+    demandMshrAccesses
+        .name(name + ".demand_mshr_accesses")
+        .desc("number of demand (read+write) mshr accesses")
+        .flags(total | nozero | nonan)
+        ;
+    demandMshrAccesses = demandMshrHits + demandMshrMisses;
+
+    overallMshrAccesses
+        .name(name + ".overall_mshr_accesses")
+        .desc("number of overall (read+write) mshr accesses")
+        .flags(total | nozero | nonan)
+        ;
+    overallMshrAccesses = overallMshrHits + overallMshrMisses
+        + overallMshrUncacheable;
+#endif
+
+    // MSHR miss rate formulas
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        mshrMissRate[access_idx]
+            .name(name + "." + cstr + "_mshr_miss_rate")
+            .desc("mshr miss rate for " + cstr + " accesses")
+            .flags(total | nozero | nonan)
+            ;
+
+        mshrMissRate[access_idx] =
+            mshr_misses[access_idx] / cache->accesses[access_idx];
+    }
+
+    demandMshrMissRate
+        .name(name + ".demand_mshr_miss_rate")
+        .desc("mshr miss rate for demand accesses")
+        .flags(total)
+        ;
+    demandMshrMissRate = demandMshrMisses / cache->demandAccesses;
+
+    overallMshrMissRate
+        .name(name + ".overall_mshr_miss_rate")
+        .desc("mshr miss rate for overall accesses")
+        .flags(total)
+        ;
+    overallMshrMissRate = overallMshrMisses / cache->overallAccesses;
+
+    // mshrMiss latency formulas
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        avgMshrMissLatency[access_idx]
+            .name(name + "." + cstr + "_avg_mshr_miss_latency")
+            .desc("average " + cstr + " mshr miss latency")
+            .flags(total | nozero | nonan)
+            ;
+
+        avgMshrMissLatency[access_idx] =
+            mshr_miss_latency[access_idx] / mshr_misses[access_idx];
+    }
+
+    demandAvgMshrMissLatency
+        .name(name + ".demand_avg_mshr_miss_latency")
+        .desc("average overall mshr miss latency")
+        .flags(total)
+        ;
+    demandAvgMshrMissLatency = demandMshrMissLatency / demandMshrMisses;
+
+    overallAvgMshrMissLatency
+        .name(name + ".overall_avg_mshr_miss_latency")
+        .desc("average overall mshr miss latency")
+        .flags(total)
+        ;
+    overallAvgMshrMissLatency = overallMshrMissLatency / overallMshrMisses;
+
+    // mshrUncacheable latency formulas
+    for (int access_idx = 0; access_idx < NUM_MEM_CMDS; ++access_idx) {
+        Packet::Command cmd = (Packet::Command)access_idx;
+        const string &cstr = temp_pkt.cmdIdxToString(cmd);
+
+        avgMshrUncacheableLatency[access_idx]
+            .name(name + "." + cstr + "_avg_mshr_uncacheable_latency")
+            .desc("average " + cstr + " mshr uncacheable latency")
+            .flags(total | nozero | nonan)
+            ;
+
+        avgMshrUncacheableLatency[access_idx] =
+            mshr_uncacheable_lat[access_idx] / mshr_uncacheable[access_idx];
+    }
+
+    overallAvgMshrUncacheableLatency
+        .name(name + ".overall_avg_mshr_uncacheable_latency")
+        .desc("average overall mshr uncacheable latency")
+        .flags(total)
+        ;
+    overallAvgMshrUncacheableLatency = overallMshrUncacheableLatency / overallMshrUncacheable;
+
+    mshr_cap_events
+        .init(maxThreadsPerCPU)
+        .name(name + ".mshr_cap_events")
+        .desc("number of times MSHR cap was activated")
+        .flags(total)
+        ;
+
+    //software prefetching stats
+    soft_prefetch_mshr_full
+        .init(maxThreadsPerCPU)
+        .name(name + ".soft_prefetch_mshr_full")
+        .desc("number of mshr full events for SW prefetching instrutions")
+        .flags(total)
+        ;
+
+    mshr_no_allocate_misses
+        .name(name +".no_allocate_misses")
+        .desc("Number of misses that were no-allocate")
+        ;
+
+}
+
+void
+MissQueue::setCache(BaseCache *_cache)
+{
+    cache = _cache;
+    blkSize = cache->getBlockSize();
+}
+
+void
+MissQueue::setPrefetcher(BasePrefetcher *_prefetcher)
+{
+    prefetcher = _prefetcher;
+}
+
+MSHR*
+MissQueue::allocateMiss(Packet * &pkt, int size, Tick time)
+{
+    MSHR* mshr = mq.allocate(pkt, size);
+    mshr->order = order++;
+    if (!pkt->req->isUncacheable() ){//&& !pkt->isNoAllocate()) {
+        // Mark this as a cache line fill
+        mshr->pkt->flags |= CACHE_LINE_FILL;
+    }
+    if (mq.isFull()) {
+        cache->setBlocked(Blocked_NoMSHRs);
+    }
+    if (pkt->cmd != Packet::HardPFReq) {
+        //If we need to request the bus (not on HW prefetch), do so
+        cache->setMasterRequest(Request_MSHR, time);
+    }
+    return mshr;
+}
+
+
+MSHR*
+MissQueue::allocateWrite(Packet * &pkt, int size, Tick time)
+{
+    MSHR* mshr = wb.allocate(pkt,pkt->getSize());
+    mshr->order = order++;
+
+//REMOVING COMPRESSION FOR NOW
+#if 0
+    if (pkt->isCompressed()) {
+        mshr->pkt->deleteData();
+        mshr->pkt->actualSize = pkt->actualSize;
+        mshr->pkt->data = new uint8_t[pkt->actualSize];
+        memcpy(mshr->pkt->data, pkt->data, pkt->actualSize);
+    } else {
+#endif
+        memcpy(mshr->pkt->getPtr<uint8_t>(), pkt->getPtr<uint8_t>(), pkt->getSize());
+  //{
+
+    if (wb.isFull()) {
+        cache->setBlocked(Blocked_NoWBBuffers);
+    }
+
+    cache->setMasterRequest(Request_WB, time);
+
+    return mshr;
+}
+
+
+/**
+ * @todo Remove SW prefetches on mshr hits.
+ */
+void
+MissQueue::handleMiss(Packet * &pkt, int blkSize, Tick time)
+{
+//    if (!cache->isTopLevel())
+    if (prefetchMiss) prefetcher->handleMiss(pkt, time);
+
+    int size = blkSize;
+    Addr blkAddr = pkt->getAddr() & ~(Addr)(blkSize-1);
+    MSHR* mshr = NULL;
+    if (!pkt->req->isUncacheable()) {
+        mshr = mq.findMatch(blkAddr, pkt->req->getAsid());
+        if (mshr) {
+            //@todo remove hw_pf here
+            mshr_hits[pkt->cmdToIndex()][pkt->req->getThreadNum()]++;
+            if (mshr->threadNum != pkt->req->getThreadNum()) {
+                mshr->threadNum = -1;
+            }
+            mq.allocateTarget(mshr, pkt);
+            if (mshr->pkt->isNoAllocate() && !pkt->isNoAllocate()) {
+                //We are adding an allocate after a no-allocate
+                mshr->pkt->flags &= ~NO_ALLOCATE;
+            }
+            if (mshr->getNumTargets() == numTarget) {
+                noTargetMSHR = mshr;
+                cache->setBlocked(Blocked_NoTargets);
+                mq.moveToFront(mshr);
+            }
+            return;
+        }
+        if (pkt->isNoAllocate()) {
+            //Count no-allocate requests differently
+            mshr_no_allocate_misses++;
+        }
+        else {
+            mshr_misses[pkt->cmdToIndex()][pkt->req->getThreadNum()]++;
+        }
+    } else {
+        //Count uncacheable accesses
+        mshr_uncacheable[pkt->cmdToIndex()][pkt->req->getThreadNum()]++;
+        size = pkt->getSize();
+    }
+    if (pkt->isWrite() && (pkt->req->isUncacheable() || !writeAllocate ||
+                               !pkt->needsResponse())) {
+        /**
+         * @todo Add write merging here.
+         */
+        mshr = allocateWrite(pkt, pkt->getSize(), time);
+        return;
+    }
+
+    mshr = allocateMiss(pkt, size, time);
+}
+
+MSHR*
+MissQueue::fetchBlock(Addr addr, int asid, int blk_size, Tick time,
+                      Packet * &target)
+{
+    Addr blkAddr = addr & ~(Addr)(blk_size - 1);
+    assert(mq.findMatch(addr, asid) == NULL);
+    MSHR *mshr = mq.allocateFetch(blkAddr, asid, blk_size, target);
+    mshr->order = order++;
+    mshr->pkt->flags |= CACHE_LINE_FILL;
+    if (mq.isFull()) {
+        cache->setBlocked(Blocked_NoMSHRs);
+    }
+    cache->setMasterRequest(Request_MSHR, time);
+    return mshr;
+}
+
+Packet *
+MissQueue::getPacket()
+{
+    Packet * pkt = mq.getReq();
+    if (((wb.isFull() && wb.inServiceMSHRs == 0) || !pkt ||
+         pkt->time > curTick) && wb.havePending()) {
+        pkt = wb.getReq();
+        // Need to search for earlier miss.
+        MSHR *mshr = mq.findPending(pkt);
+        if (mshr && mshr->order < ((MSHR*)(pkt->senderState))->order) {
+            // Service misses in order until conflict is cleared.
+            return mq.getReq();
+        }
+    }
+    if (pkt) {
+        MSHR* mshr = wb.findPending(pkt);
+        if (mshr /*&& mshr->order < pkt->senderState->order*/) {
+            // The only way this happens is if we are
+            // doing a write and we didn't have permissions
+            // then subsequently saw a writeback(owned got evicted)
+            // We need to make sure to perform the writeback first
+            // To preserve the dirty data, then we can issue the write
+            return wb.getReq();
+        }
+    }
+    else if (!mq.isFull()){
+        //If we have a miss queue slot, we can try a prefetch
+        pkt = prefetcher->getPacket();
+        if (pkt) {
+            //Update statistic on number of prefetches issued (hwpf_mshr_misses)
+            mshr_misses[pkt->cmdToIndex()][pkt->req->getThreadNum()]++;
+            //It will request the bus for the future, but should clear that immedieatley
+            allocateMiss(pkt, pkt->getSize(), curTick);
+            pkt = mq.getReq();
+            assert(pkt); //We should get back a req b/c we just put one in
+        }
+    }
+    return pkt;
+}
+
+void
+MissQueue::setBusCmd(Packet * &pkt, Packet::Command cmd)
+{
+    assert(pkt->senderState != 0);
+    MSHR * mshr = (MSHR*)pkt->senderState;
+    mshr->originalCmd = pkt->cmd;
+    if (pkt->isCacheFill() || pkt->isNoAllocate())
+        pkt->cmd = cmd;
+}
+
+void
+MissQueue::restoreOrigCmd(Packet * &pkt)
+{
+    pkt->cmd = ((MSHR*)(pkt->senderState))->originalCmd;
+}
+
+void
+MissQueue::markInService(Packet * &pkt)
+{
+    assert(pkt->senderState != 0);
+    bool unblock = false;
+    BlockedCause cause = NUM_BLOCKED_CAUSES;
+
+    /**
+     * @todo Should include MSHRQueue pointer in MSHR to select the correct
+     * one.
+     */
+    if ((!pkt->isCacheFill() && pkt->isWrite())) {
+        // Forwarding a write/ writeback, don't need to change
+        // the command
+        unblock = wb.isFull();
+        wb.markInService((MSHR*)pkt->senderState);
+        if (!wb.havePending()){
+            cache->clearMasterRequest(Request_WB);
+        }
+        if (unblock) {
+            // Do we really unblock?
+            unblock = !wb.isFull();
+            cause = Blocked_NoWBBuffers;
+        }
+    } else {
+        unblock = mq.isFull();
+        mq.markInService((MSHR*)pkt->senderState);
+        if (!mq.havePending()){
+            cache->clearMasterRequest(Request_MSHR);
+        }
+        if (((MSHR*)(pkt->senderState))->originalCmd == Packet::HardPFReq) {
+            DPRINTF(HWPrefetch, "%s:Marking a HW_PF in service\n",
+                    cache->name());
+            //Also clear pending if need be
+            if (!prefetcher->havePending())
+            {
+                cache->clearMasterRequest(Request_PF);
+            }
+        }
+        if (unblock) {
+            unblock = !mq.isFull();
+            cause = Blocked_NoMSHRs;
+        }
+    }
+    if (unblock) {
+        cache->clearBlocked(cause);
+    }
+}
+
+
+void
+MissQueue::handleResponse(Packet * &pkt, Tick time)
+{
+    MSHR* mshr = (MSHR*)pkt->senderState;
+    if (((MSHR*)(pkt->senderState))->originalCmd == Packet::HardPFReq) {
+        DPRINTF(HWPrefetch, "%s:Handling the response to a HW_PF\n",
+                cache->name());
+    }
+#ifndef NDEBUG
+    int num_targets = mshr->getNumTargets();
+#endif
+
+    bool unblock = false;
+    bool unblock_target = false;
+    BlockedCause cause = NUM_BLOCKED_CAUSES;
+
+    if (pkt->isCacheFill() && !pkt->isNoAllocate()) {
+        mshr_miss_latency[mshr->originalCmd][pkt->req->getThreadNum()] +=
+            curTick - pkt->time;
+        // targets were handled in the cache tags
+        if (mshr == noTargetMSHR) {
+            // we always clear at least one target
+            unblock_target = true;
+            cause = Blocked_NoTargets;
+            noTargetMSHR = NULL;
+        }
+
+        if (mshr->hasTargets()) {
+            // Didn't satisfy all the targets, need to resend
+            Packet::Command cmd = mshr->getTarget()->cmd;
+            mq.markPending(mshr, cmd);
+            mshr->order = order++;
+            cache->setMasterRequest(Request_MSHR, time);
+        }
+        else {
+            unblock = mq.isFull();
+            mq.deallocate(mshr);
+            if (unblock) {
+                unblock = !mq.isFull();
+                cause = Blocked_NoMSHRs;
+            }
+        }
+    } else {
+        if (pkt->req->isUncacheable()) {
+            mshr_uncacheable_lat[pkt->cmd][pkt->req->getThreadNum()] +=
+                curTick - pkt->time;
+        }
+        if (mshr->hasTargets() && pkt->req->isUncacheable()) {
+            // Should only have 1 target if we had any
+            assert(num_targets == 1);
+            Packet * target = mshr->getTarget();
+            mshr->popTarget();
+            if (pkt->isRead()) {
+                memcpy(target->getPtr<uint8_t>(), pkt->getPtr<uint8_t>(),
+                       target->getSize());
+            }
+            cache->respond(target, time);
+            assert(!mshr->hasTargets());
+        }
+        else if (mshr->hasTargets()) {
+            //Must be a no_allocate with possibly more than one target
+            assert(mshr->pkt->isNoAllocate());
+            while (mshr->hasTargets()) {
+                Packet * target = mshr->getTarget();
+                mshr->popTarget();
+                if (pkt->isRead()) {
+                    memcpy(target->getPtr<uint8_t>(), pkt->getPtr<uint8_t>(),
+                           target->getSize());
+                }
+                cache->respond(target, time);
+            }
+        }
+
+        if (pkt->isWrite()) {
+            // If the wrtie buffer is full, we might unblock now
+            unblock = wb.isFull();
+            wb.deallocate(mshr);
+            if (unblock) {
+                // Did we really unblock?
+                unblock = !wb.isFull();
+                cause = Blocked_NoWBBuffers;
+            }
+        } else {
+            unblock = mq.isFull();
+            mq.deallocate(mshr);
+            if (unblock) {
+                unblock = !mq.isFull();
+                cause = Blocked_NoMSHRs;
+            }
+        }
+    }
+    if (unblock || unblock_target) {
+        cache->clearBlocked(cause);
+    }
+}
+
+void
+MissQueue::squash(int threadNum)
+{
+    bool unblock = false;
+    BlockedCause cause = NUM_BLOCKED_CAUSES;
+
+    if (noTargetMSHR && noTargetMSHR->threadNum == threadNum) {
+        noTargetMSHR = NULL;
+        unblock = true;
+        cause = Blocked_NoTargets;
+    }
+    if (mq.isFull()) {
+        unblock = true;
+        cause = Blocked_NoMSHRs;
+    }
+    mq.squash(threadNum);
+    if (!mq.havePending()) {
+        cache->clearMasterRequest(Request_MSHR);
+    }
+    if (unblock && !mq.isFull()) {
+        cache->clearBlocked(cause);
+    }
+
+}
+
+MSHR*
+MissQueue::findMSHR(Addr addr, int asid) const
+{
+    return mq.findMatch(addr,asid);
+}
+
+bool
+MissQueue::findWrites(Addr addr, int asid, vector<MSHR*> &writes) const
+{
+    return wb.findMatches(addr,asid,writes);
+}
+
+void
+MissQueue::doWriteback(Addr addr, int asid,
+                       int size, uint8_t *data, bool compressed)
+{
+    // Generate request
+    Request * req = new Request(addr, size, 0);
+    Packet * pkt = new Packet(req, Packet::Writeback, -1);
+    uint8_t *new_data = new uint8_t[size];
+    pkt->dataDynamicArray<uint8_t>(new_data);
+    if (data) {
+        memcpy(pkt->getPtr<uint8_t>(), data, size);
+    }
+
+    if (compressed) {
+        pkt->flags |= COMPRESSED;
+    }
+
+    ///All writebacks charged to same thread @todo figure this out
+    writebacks[pkt->req->getThreadNum()]++;
+
+    allocateWrite(pkt, 0, curTick);
+}
+
+
+void
+MissQueue::doWriteback(Packet * &pkt)
+{
+    writebacks[pkt->req->getThreadNum()]++;
+    allocateWrite(pkt, 0, curTick);
+}
+
+
+MSHR*
+MissQueue::allocateTargetList(Addr addr, int asid)
+{
+   MSHR* mshr = mq.allocateTargetList(addr, asid, blkSize);
+   mshr->pkt->flags |= CACHE_LINE_FILL;
+   if (mq.isFull()) {
+       cache->setBlocked(Blocked_NoMSHRs);
+   }
+   return mshr;
+}
+
+bool
+MissQueue::havePending()
+{
+    return mq.havePending() || wb.havePending() || prefetcher->havePending();
+}
diff --git a/src/mem/cache/miss/miss_queue.hh b/src/mem/cache/miss/miss_queue.hh
new file mode 100644
index 000000000..b88b7038c
--- /dev/null
+++ b/src/mem/cache/miss/miss_queue.hh
@@ -0,0 +1,349 @@
+/*
+ * Copyright (c) 2003-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ */
+
+/**
+ * @file
+ * Miss and writeback queue declarations.
+ */
+
+#ifndef __MISS_QUEUE_HH__
+#define __MISS_QUEUE_HH__
+
+#include <vector>
+
+#include "mem/cache/miss/mshr.hh"
+#include "mem/cache/miss/mshr_queue.hh"
+#include "base/statistics.hh"
+
+class BaseCache;
+class BasePrefetcher;
+/**
+ * Manages cache misses and writebacks. Contains MSHRs to store miss data
+ * and the writebuffer for writes/writebacks.
+ * @todo need to handle data on writes better (encapsulate).
+ * @todo need to make replacements/writebacks happen in Cache::access
+ */
+class MissQueue
+{
+  protected:
+    /** The MSHRs. */
+    MSHRQueue mq;
+    /** Write Buffer. */
+    MSHRQueue wb;
+
+    // PARAMTERS
+
+    /** The number of MSHRs in the miss queue. */
+    const int numMSHR;
+    /** The number of targets for each MSHR. */
+    const int numTarget;
+    /** The number of write buffers. */
+    const int writeBuffers;
+    /** True if the cache should allocate on a write miss. */
+    const bool writeAllocate;
+    /** Pointer to the parent cache. */
+    BaseCache* cache;
+
+    /** The Prefetcher */
+    BasePrefetcher *prefetcher;
+
+    /** The block size of the parent cache. */
+    int blkSize;
+
+    /** Increasing order number assigned to each incoming request. */
+    uint64_t order;
+
+    bool prefetchMiss;
+
+    // Statistics
+    /**
+     * @addtogroup CacheStatistics
+     * @{
+     */
+    /** Number of blocks written back per thread. */
+    Stats::Vector<> writebacks;
+
+    /** Number of misses that hit in the MSHRs per command and thread. */
+    Stats::Vector<> mshr_hits[NUM_MEM_CMDS];
+    /** Demand misses that hit in the MSHRs. */
+    Stats::Formula demandMshrHits;
+    /** Total number of misses that hit in the MSHRs. */
+    Stats::Formula overallMshrHits;
+
+    /** Number of misses that miss in the MSHRs, per command and thread. */
+    Stats::Vector<> mshr_misses[NUM_MEM_CMDS];
+    /** Demand misses that miss in the MSHRs. */
+    Stats::Formula demandMshrMisses;
+    /** Total number of misses that miss in the MSHRs. */
+    Stats::Formula overallMshrMisses;
+
+    /** Number of misses that miss in the MSHRs, per command and thread. */
+    Stats::Vector<> mshr_uncacheable[NUM_MEM_CMDS];
+    /** Total number of misses that miss in the MSHRs. */
+    Stats::Formula overallMshrUncacheable;
+
+    /** Total cycle latency of each MSHR miss, per command and thread. */
+    Stats::Vector<> mshr_miss_latency[NUM_MEM_CMDS];
+    /** Total cycle latency of demand MSHR misses. */
+    Stats::Formula demandMshrMissLatency;
+    /** Total cycle latency of overall MSHR misses. */
+    Stats::Formula overallMshrMissLatency;
+
+    /** Total cycle latency of each MSHR miss, per command and thread. */
+    Stats::Vector<> mshr_uncacheable_lat[NUM_MEM_CMDS];
+    /** Total cycle latency of overall MSHR misses. */
+    Stats::Formula overallMshrUncacheableLatency;
+
+    /** The total number of MSHR accesses per command and thread. */
+    Stats::Formula mshrAccesses[NUM_MEM_CMDS];
+    /** The total number of demand MSHR accesses. */
+    Stats::Formula demandMshrAccesses;
+    /** The total number of MSHR accesses. */
+    Stats::Formula overallMshrAccesses;
+
+    /** The miss rate in the MSHRs pre command and thread. */
+    Stats::Formula mshrMissRate[NUM_MEM_CMDS];
+    /** The demand miss rate in the MSHRs. */
+    Stats::Formula demandMshrMissRate;
+    /** The overall miss rate in the MSHRs. */
+    Stats::Formula overallMshrMissRate;
+
+    /** The average latency of an MSHR miss, per command and thread. */
+    Stats::Formula avgMshrMissLatency[NUM_MEM_CMDS];
+    /** The average latency of a demand MSHR miss. */
+    Stats::Formula demandAvgMshrMissLatency;
+    /** The average overall latency of an MSHR miss. */
+    Stats::Formula overallAvgMshrMissLatency;
+
+    /** The average latency of an MSHR miss, per command and thread. */
+    Stats::Formula avgMshrUncacheableLatency[NUM_MEM_CMDS];
+    /** The average overall latency of an MSHR miss. */
+    Stats::Formula overallAvgMshrUncacheableLatency;
+
+    /** The number of times a thread hit its MSHR cap. */
+    Stats::Vector<> mshr_cap_events;
+    /** The number of times software prefetches caused the MSHR to block. */
+    Stats::Vector<> soft_prefetch_mshr_full;
+
+    Stats::Scalar<> mshr_no_allocate_misses;
+
+    /**
+     * @}
+     */
+
+  private:
+    /** Pointer to the MSHR that has no targets. */
+    MSHR* noTargetMSHR;
+
+    /**
+     * Allocate a new MSHR to handle the provided miss.
+     * @param req The miss to buffer.
+     * @param size The number of bytes to fetch.
+     * @param time The time the miss occurs.
+     * @return A pointer to the new MSHR.
+     */
+    MSHR* allocateMiss(Packet * &pkt, int size, Tick time);
+
+    /**
+     * Allocate a new WriteBuffer to handle the provided write.
+     * @param req The write to handle.
+     * @param size The number of bytes to write.
+     * @param time The time the write occurs.
+     * @return A pointer to the new write buffer.
+     */
+    MSHR* allocateWrite(Packet * &pkt, int size, Tick time);
+
+  public:
+    /**
+     * Simple Constructor. Initializes all needed internal storage and sets
+     * parameters.
+     * @param numMSHRs The number of outstanding misses to handle.
+     * @param numTargets The number of outstanding targets to each miss.
+     * @param write_buffers The number of outstanding writes to handle.
+     * @param write_allocate If true, treat write misses the same as reads.
+     */
+    MissQueue(int numMSHRs, int numTargets, int write_buffers,
+              bool write_allocate, bool prefetch_miss);
+
+    /**
+     * Deletes all allocated internal storage.
+     */
+    ~MissQueue();
+
+    /**
+     * Register statistics for this object.
+     * @param name The name of the parent cache.
+     */
+    void regStats(const std::string &name);
+
+    /**
+     * Called by the parent cache to set the back pointer.
+     * @param _cache A pointer to the parent cache.
+     */
+    void setCache(BaseCache *_cache);
+
+    void setPrefetcher(BasePrefetcher *_prefetcher);
+
+    /**
+     * Handle a cache miss properly. Either allocate an MSHR for the request,
+     * or forward it through the write buffer.
+     * @param req The request that missed in the cache.
+     * @param blk_size The block size of the cache.
+     * @param time The time the miss is detected.
+     */
+    void handleMiss(Packet * &pkt, int blk_size, Tick time);
+
+    /**
+     * Fetch the block for the given address and buffer the given target.
+     * @param addr The address to fetch.
+     * @param asid The address space of the address.
+     * @param blk_size The block size of the cache.
+     * @param time The time the miss is detected.
+     * @param target The target for the fetch.
+     */
+    MSHR* fetchBlock(Addr addr, int asid, int blk_size, Tick time,
+                     Packet * &target);
+
+    /**
+     * Selects a outstanding request to service.
+     * @return The request to service, NULL if none found.
+     */
+    Packet * getPacket();
+
+    /**
+     * Set the command to the given bus command.
+     * @param req The request to update.
+     * @param cmd The bus command to use.
+     */
+    void setBusCmd(Packet * &pkt, Packet::Command cmd);
+
+    /**
+     * Restore the original command in case of a bus transmission error.
+     * @param req The request to reset.
+     */
+    void restoreOrigCmd(Packet * &pkt);
+
+    /**
+     * Marks a request as in service (sent on the bus). This can have side
+     * effect since storage for no response commands is deallocated once they
+     * are successfully sent.
+     * @param req The request that was sent on the bus.
+     */
+    void markInService(Packet * &pkt);
+
+    /**
+     * Collect statistics and free resources of a satisfied request.
+     * @param req The request that has been satisfied.
+     * @param time The time when the request is satisfied.
+     */
+    void handleResponse(Packet * &pkt, Tick time);
+
+    /**
+     * Removes all outstanding requests for a given thread number. If a request
+     * has been sent to the bus, this function removes all of its targets.
+     * @param req->getThreadNum()ber The thread number of the requests to squash.
+     */
+    void squash(int threadNum);
+
+    /**
+     * Return the current number of outstanding misses.
+     * @return the number of outstanding misses.
+     */
+    int getMisses()
+    {
+        return mq.getAllocatedTargets();
+    }
+
+    /**
+     * Searches for the supplied address in the miss queue.
+     * @param addr The address to look for.
+     * @param asid The address space id.
+     * @return The MSHR that contains the address, NULL if not found.
+     * @warning Currently only searches the miss queue. If non write allocate
+     * might need to search the write buffer for coherence.
+     */
+    MSHR* findMSHR(Addr addr, int asid) const;
+
+    /**
+     * Searches for the supplied address in the write buffer.
+     * @param addr The address to look for.
+     * @param asid The address space id.
+     * @param writes The list of writes that match the address.
+     * @return True if any writes are found
+     */
+    bool findWrites(Addr addr, int asid, std::vector<MSHR*>& writes) const;
+
+    /**
+     * Perform a writeback of dirty data to the given address.
+     * @param addr The address to write to.
+     * @param asid The address space id.
+     * @param xc The execution context of the address space.
+     * @param size The number of bytes to write.
+     * @param data The data to write, can be NULL.
+     * @param compressed True if the data is compressed.
+     */
+    void doWriteback(Addr addr, int asid,
+                     int size, uint8_t *data, bool compressed);
+
+    /**
+     * Perform the given writeback request.
+     * @param req The writeback request.
+     */
+    void doWriteback(Packet * &pkt);
+
+    /**
+     * Returns true if there are outstanding requests.
+     * @return True if there are outstanding requests.
+     */
+    bool havePending();
+
+    /**
+     * Add a target to the given MSHR. This assumes it is in the miss queue.
+     * @param mshr The mshr to add a target to.
+     * @param req The target to add.
+     */
+    void addTarget(MSHR *mshr, Packet * &pkt)
+    {
+        mq.allocateTarget(mshr, pkt);
+    }
+
+    /**
+     * Allocate a MSHR to hold a list of targets to a block involved in a copy.
+     * If the block is marked done then the MSHR already holds the data to
+     * fill the block. Otherwise the block needs to be fetched.
+     * @param addr The address to buffer.
+     * @param asid The address space ID.
+     * @return A pointer to the allocated MSHR.
+     */
+    MSHR* allocateTargetList(Addr addr, int asid);
+
+};
+
+#endif //__MISS_QUEUE_HH__
diff --git a/src/mem/cache/miss/mshr.cc b/src/mem/cache/miss/mshr.cc
new file mode 100644
index 000000000..fe8cbeea4
--- /dev/null
+++ b/src/mem/cache/miss/mshr.cc
@@ -0,0 +1,182 @@
+/*
+ * Copyright (c) 2002-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ *          Dave Greene
+ */
+
+/**
+ * @file
+ * Miss Status and Handling Register (MSHR) definitions.
+ */
+
+#include <assert.h>
+#include <string>
+#include <vector>
+
+#include "mem/cache/miss/mshr.hh"
+#include "sim/root.hh" // for curTick
+#include "sim/host.hh"
+#include "base/misc.hh"
+#include "mem/cache/cache.hh"
+
+using namespace std;
+
+MSHR::MSHR()
+{
+    inService = false;
+    ntargets = 0;
+    threadNum = -1;
+}
+
+void
+MSHR::allocate(Packet::Command cmd, Addr _addr, int _asid, int size,
+               Packet * &target)
+{
+    assert("NEED TO FIX YET\n" && 0);
+#if 0
+    assert(targets.empty());
+    addr = _addr;
+    asid = _asid;
+
+    pkt = new Packet(); // allocate new memory request
+    pkt->addr = addr; //picked physical address for now
+    pkt->cmd = cmd;
+    pkt->size = size;
+    pkt->data = new uint8_t[size];
+    pkt->senderState = this;
+    //Set the time here for latency calculations
+    pkt->time = curTick;
+
+    if (target) {
+        pkt->req = target->req;
+        allocateTarget(target);
+    }
+#endif
+}
+
+// Since we aren't sure if data is being used, don't copy here.
+/**
+ * @todo When we have a "global" data flag, might want to copy data here.
+ */
+void
+MSHR::allocateAsBuffer(Packet * &target)
+{
+    addr = target->getAddr();
+    asid = target->req->getAsid();
+    threadNum = target->req->getThreadNum();
+    pkt = new Packet(target->req, target->cmd, -1);
+    uint8_t *new_data = new uint8_t[target->getSize()];
+    pkt->dataDynamicArray<uint8_t>(new_data);
+    pkt->senderState = (Packet::SenderState*)this;
+    pkt->time = curTick;
+}
+
+void
+MSHR::deallocate()
+{
+    assert(targets.empty());
+    assert(ntargets == 0);
+    pkt = NULL;
+    inService = false;
+    allocIter = NULL;
+    readyIter = NULL;
+}
+
+/*
+ * Adds a target to an MSHR
+ */
+void
+MSHR::allocateTarget(Packet * &target)
+{
+    //If we append an invalidate and we issued a read to the bus,
+    //but now have some pending writes, we need to move
+    //the invalidate to before the first non-read
+    if (inService && pkt->isRead() && target->isInvalidate()) {
+        std::list<Packet *> temp;
+
+        while (!targets.empty()) {
+            if (!targets.front()->isRead()) break;
+            //Place on top of temp stack
+            temp.push_front(targets.front());
+            //Remove from targets
+            targets.pop_front();
+        }
+
+        //Now that we have all the reads off until first non-read, we can
+        //place the invalidate on
+        targets.push_front(target);
+
+        //Now we pop off the temp_stack and put them back
+        while (!temp.empty()) {
+            targets.push_front(temp.front());
+            temp.pop_front();
+        }
+    }
+    else {
+        targets.push_back(target);
+    }
+
+    ++ntargets;
+    assert(targets.size() == ntargets);
+    /**
+     * @todo really prioritize the target commands.
+     */
+
+    if (!inService && target->isWrite()) {
+        pkt->cmd = Packet::WriteReq;
+    }
+}
+
+
+
+void
+MSHR::dump()
+{
+    ccprintf(cerr,
+             "inService: %d thread: %d\n"
+             "Addr: %x asid: %d ntargets %d\n"
+             "Targets:\n",
+             inService, threadNum, addr, asid, ntargets);
+
+    TargetListIterator tar_it = targets.begin();
+    for (int i = 0; i < ntargets; i++) {
+        assert(tar_it != targets.end());
+
+        ccprintf(cerr, "\t%d: Addr: %x cmd: %d\n",
+                 i, (*tar_it)->getAddr(), (*tar_it)->cmdToIndex());
+
+        tar_it++;
+    }
+    ccprintf(cerr, "\n");
+}
+
+MSHR::~MSHR()
+{
+    if (pkt)
+        pkt = NULL;
+}
diff --git a/src/mem/cache/miss/mshr.hh b/src/mem/cache/miss/mshr.hh
new file mode 100644
index 000000000..167aa26cd
--- /dev/null
+++ b/src/mem/cache/miss/mshr.hh
@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2002-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ */
+
+/**
+ * @file
+ * Miss Status and Handling Register (MSHR) declaration.
+ */
+
+#ifndef __MSHR_HH__
+#define __MSHR_HH__
+
+#include "mem/packet.hh"
+#include <list>
+#include <deque>
+
+class MSHR;
+
+/**
+ * Miss Status and handling Register. This class keeps all the information
+ * needed to handle a cache miss including a list of target requests.
+ */
+class MSHR {
+  public:
+    /** Defines the Data structure of the MSHR targetlist. */
+    typedef std::list<Packet *> TargetList;
+    /** Target list iterator. */
+    typedef std::list<Packet *>::iterator TargetListIterator;
+    /** A list of MSHRs. */
+    typedef std::list<MSHR *> List;
+    /** MSHR list iterator. */
+    typedef List::iterator Iterator;
+    /** MSHR list const_iterator. */
+    typedef List::const_iterator ConstIterator;
+
+    /** Address of the miss. */
+    Addr addr;
+    /** Adress space id of the miss. */
+    short asid;
+    /** True if the request has been sent to the bus. */
+    bool inService;
+    /** Thread number of the miss. */
+    int threadNum;
+    /** The request that is forwarded to the next level of the hierarchy. */
+    Packet * pkt;
+    /** The number of currently allocated targets. */
+    short ntargets;
+    /** The original requesting command. */
+    Packet::Command originalCmd;
+    /** Order number of assigned by the miss queue. */
+    uint64_t order;
+
+    /**
+     * Pointer to this MSHR on the ready list.
+     * @sa MissQueue, MSHRQueue::readyList
+     */
+    Iterator readyIter;
+    /**
+     * Pointer to this MSHR on the allocated list.
+     * @sa MissQueue, MSHRQueue::allocatedList
+     */
+    Iterator allocIter;
+
+private:
+    /** List of all requests that match the address */
+    TargetList targets;
+
+public:
+    /**
+     * Allocate a miss to this MSHR.
+     * @param cmd The requesting command.
+     * @param addr The address of the miss.
+     * @param asid The address space id of the miss.
+     * @param size The number of bytes to request.
+     * @param req  The original miss.
+     */
+    void allocate(Packet::Command cmd, Addr addr, int asid, int size,
+                  Packet * &pkt);
+
+    /**
+     * Allocate this MSHR as a buffer for the given request.
+     * @param target The memory request to buffer.
+     */
+    void allocateAsBuffer(Packet * &target);
+
+    /**
+     * Mark this MSHR as free.
+     */
+    void deallocate();
+
+    /**
+     * Add a request to the list of targets.
+     * @param target The target.
+     */
+    void allocateTarget(Packet * &target);
+
+    /** A simple constructor. */
+    MSHR();
+    /** A simple destructor. */
+    ~MSHR();
+
+    /**
+     * Returns the current number of allocated targets.
+     * @return The current number of allocated targets.
+     */
+    int getNumTargets()
+    {
+        return(ntargets);
+    }
+
+    /**
+     * Returns a pointer to the target list.
+     * @return a pointer to the target list.
+     */
+    TargetList* getTargetList()
+    {
+        return &targets;
+    }
+
+    /**
+     * Returns a reference to the first target.
+     * @return A pointer to the first target.
+     */
+    Packet * getTarget()
+    {
+        return targets.front();
+    }
+
+    /**
+     * Pop first target.
+     */
+    void popTarget()
+    {
+        --ntargets;
+        targets.pop_front();
+    }
+
+    /**
+     * Returns true if there are targets left.
+     * @return true if there are targets
+     */
+    bool hasTargets()
+    {
+        return !targets.empty();
+    }
+
+    /**
+     * Prints the contents of this MSHR to stderr.
+     */
+    void dump();
+};
+
+#endif //__MSHR_HH__
diff --git a/src/mem/cache/miss/mshr_queue.cc b/src/mem/cache/miss/mshr_queue.cc
new file mode 100644
index 000000000..6516a99f8
--- /dev/null
+++ b/src/mem/cache/miss/mshr_queue.cc
@@ -0,0 +1,269 @@
+/*
+ * Copyright (c) 2003-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ */
+
+/** @file
+ * Definition of the MSHRQueue.
+ */
+
+#include "mem/cache/miss/mshr_queue.hh"
+#include "sim/eventq.hh"
+
+using namespace std;
+
+MSHRQueue::MSHRQueue(int num_mshrs, int reserve)
+    : numMSHRs(num_mshrs + reserve - 1), numReserve(reserve)
+{
+    allocated = 0;
+    inServiceMSHRs = 0;
+    allocatedTargets = 0;
+    registers = new MSHR[numMSHRs];
+    for (int i = 0; i < numMSHRs; ++i) {
+        freeList.push_back(&registers[i]);
+    }
+}
+
+MSHRQueue::~MSHRQueue()
+{
+    delete [] registers;
+}
+
+MSHR*
+MSHRQueue::findMatch(Addr addr, int asid) const
+{
+    MSHR::ConstIterator i = allocatedList.begin();
+    MSHR::ConstIterator end = allocatedList.end();
+    for (; i != end; ++i) {
+        MSHR *mshr = *i;
+        if (mshr->addr == addr) {
+            return mshr;
+        }
+    }
+    return NULL;
+}
+
+bool
+MSHRQueue::findMatches(Addr addr, int asid, vector<MSHR*>& matches) const
+{
+    // Need an empty vector
+    assert(matches.empty());
+    bool retval = false;
+    MSHR::ConstIterator i = allocatedList.begin();
+    MSHR::ConstIterator end = allocatedList.end();
+    for (; i != end; ++i) {
+        MSHR *mshr = *i;
+        if (mshr->addr == addr) {
+            retval = true;
+            matches.push_back(mshr);
+        }
+    }
+    return retval;
+
+}
+
+MSHR*
+MSHRQueue::findPending(Packet * &pkt) const
+{
+    MSHR::ConstIterator i = pendingList.begin();
+    MSHR::ConstIterator end = pendingList.end();
+    for (; i != end; ++i) {
+        MSHR *mshr = *i;
+        if (mshr->addr < pkt->getAddr()) {
+            if (mshr->addr + mshr->pkt->getSize() > pkt->getAddr()) {
+                return mshr;
+            }
+        } else {
+            if (pkt->getAddr() + pkt->getSize() > mshr->addr) {
+                return mshr;
+            }
+        }
+
+        //need to check destination address for copies.
+        //TEMP NOT DOING COPIES
+#if 0
+        if (mshr->pkt->cmd == Copy) {
+            Addr dest = mshr->pkt->dest;
+            if (dest < pkt->addr) {
+                if (dest + mshr->pkt->size > pkt->addr) {
+                    return mshr;
+                }
+            } else {
+                if (pkt->addr + pkt->size > dest) {
+                    return mshr;
+                }
+            }
+        }
+#endif
+    }
+    return NULL;
+}
+
+MSHR*
+MSHRQueue::allocate(Packet * &pkt, int size)
+{
+    Addr aligned_addr = pkt->getAddr() & ~((Addr)size - 1);
+    MSHR *mshr = freeList.front();
+    assert(mshr->getNumTargets() == 0);
+    freeList.pop_front();
+
+    if (!pkt->needsResponse()) {
+        mshr->allocateAsBuffer(pkt);
+    } else {
+        assert(size !=0);
+        mshr->allocate(pkt->cmd, aligned_addr, pkt->req->getAsid(), size, pkt);
+        allocatedTargets += 1;
+    }
+    mshr->allocIter = allocatedList.insert(allocatedList.end(), mshr);
+    mshr->readyIter = pendingList.insert(pendingList.end(), mshr);
+
+    allocated += 1;
+    return mshr;
+}
+
+MSHR*
+MSHRQueue::allocateFetch(Addr addr, int asid, int size, Packet * &target)
+{
+    MSHR *mshr = freeList.front();
+    assert(mshr->getNumTargets() == 0);
+    freeList.pop_front();
+    mshr->allocate(Packet::ReadReq, addr, asid, size, target);
+    mshr->allocIter = allocatedList.insert(allocatedList.end(), mshr);
+    mshr->readyIter = pendingList.insert(pendingList.end(), mshr);
+
+    allocated += 1;
+    return mshr;
+}
+
+MSHR*
+MSHRQueue::allocateTargetList(Addr addr, int asid, int size)
+{
+    MSHR *mshr = freeList.front();
+    assert(mshr->getNumTargets() == 0);
+    freeList.pop_front();
+    Packet * dummy;
+    mshr->allocate(Packet::ReadReq, addr, asid, size, dummy);
+    mshr->allocIter = allocatedList.insert(allocatedList.end(), mshr);
+    mshr->inService = true;
+    ++inServiceMSHRs;
+    ++allocated;
+    return mshr;
+}
+
+
+void
+MSHRQueue::deallocate(MSHR* mshr)
+{
+    deallocateOne(mshr);
+}
+
+MSHR::Iterator
+MSHRQueue::deallocateOne(MSHR* mshr)
+{
+    MSHR::Iterator retval = allocatedList.erase(mshr->allocIter);
+    freeList.push_front(mshr);
+    allocated--;
+    allocatedTargets -= mshr->getNumTargets();
+    if (mshr->inService) {
+        inServiceMSHRs--;
+    } else {
+        pendingList.erase(mshr->readyIter);
+    }
+    mshr->deallocate();
+    return retval;
+}
+
+void
+MSHRQueue::moveToFront(MSHR *mshr)
+{
+    if (!mshr->inService) {
+        assert(mshr == *(mshr->readyIter));
+        pendingList.erase(mshr->readyIter);
+        mshr->readyIter = pendingList.insert(pendingList.begin(), mshr);
+    }
+}
+
+void
+MSHRQueue::markInService(MSHR* mshr)
+{
+    //assert(mshr == pendingList.front());
+    if (!mshr->pkt->needsResponse()) {
+        assert(mshr->getNumTargets() == 0);
+        deallocate(mshr);
+        return;
+    }
+    mshr->inService = true;
+    pendingList.erase(mshr->readyIter);
+    mshr->readyIter = NULL;
+    inServiceMSHRs += 1;
+    //pendingList.pop_front();
+}
+
+void
+MSHRQueue::markPending(MSHR* mshr, Packet::Command cmd)
+{
+    assert(mshr->readyIter == NULL);
+    mshr->pkt->cmd = cmd;
+    mshr->pkt->flags &= ~SATISFIED;
+    mshr->inService = false;
+    --inServiceMSHRs;
+    /**
+     * @ todo might want to add rerequests to front of pending list for
+     * performance.
+     */
+    mshr->readyIter = pendingList.insert(pendingList.end(), mshr);
+}
+
+void
+MSHRQueue::squash(int threadNum)
+{
+    MSHR::Iterator i = allocatedList.begin();
+    MSHR::Iterator end = allocatedList.end();
+    for (; i != end;) {
+        MSHR *mshr = *i;
+        if (mshr->threadNum == threadNum) {
+            while (mshr->hasTargets()) {
+                Packet * target = mshr->getTarget();
+                mshr->popTarget();
+
+                assert(target->req->getThreadNum() == threadNum);
+                target = NULL;
+            }
+            assert(!mshr->hasTargets());
+            assert(mshr->ntargets==0);
+            if (!mshr->inService) {
+                i = deallocateOne(mshr);
+            } else {
+                //mshr->pkt->flags &= ~CACHE_LINE_FILL;
+                ++i;
+            }
+        } else {
+            ++i;
+        }
+    }
+}
diff --git a/src/mem/cache/miss/mshr_queue.hh b/src/mem/cache/miss/mshr_queue.hh
new file mode 100644
index 000000000..a67f1b9a6
--- /dev/null
+++ b/src/mem/cache/miss/mshr_queue.hh
@@ -0,0 +1,239 @@
+/*
+ * Copyright (c) 2003-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Erik Hallnor
+ */
+
+/** @file
+ * Declaration of a structure to manage MSHRs.
+ */
+
+#ifndef __MSHR_QUEUE_HH__
+#define __MSHR_QUEUE_HH__
+
+#include <vector>
+#include "mem/cache/miss/mshr.hh"
+
+/**
+ * A Class for maintaining a list of pending and allocated memory requests.
+ */
+class MSHRQueue {
+  private:
+    /**  MSHR storage. */
+    MSHR* registers;
+    /** Holds pointers to all allocated MSHRs. */
+    MSHR::List allocatedList;
+    /** Holds pointers to MSHRs that haven't been sent to the bus. */
+    MSHR::List pendingList;
+    /** Holds non allocated MSHRs. */
+    MSHR::List freeList;
+
+    // Parameters
+    /**
+     * The total number of MSHRs in this queue. This number is set as the
+     * number of MSHRs requested plus (numReserve - 1). This allows for
+     * the same number of effective MSHRs while still maintaining the reserve.
+     */
+    const int numMSHRs;
+
+    /**
+     * The number of MSHRs to hold in reserve. This is needed because copy
+     * operations can allocate upto 4 MSHRs at one time.
+     */
+    const int numReserve;
+
+  public:
+    /** The number of allocated MSHRs. */
+    int allocated;
+    /** The number of MSHRs that have been forwarded to the bus. */
+    int inServiceMSHRs;
+    /** The number of targets waiting for response. */
+    int allocatedTargets;
+
+    /**
+     * Create a queue with a given number of MSHRs.
+     * @param num_mshrs The number of MSHRs in this queue.
+     * @param reserve The minimum number of MSHRs needed to satisfy any access.
+     */
+    MSHRQueue(int num_mshrs, int reserve = 1);
+
+    /** Destructor */
+    ~MSHRQueue();
+
+    /**
+     * Find the first MSHR that matches the provide address and asid.
+     * @param addr The address to find.
+     * @param asid The address space id.
+     * @return Pointer to the matching MSHR, null if not found.
+     */
+    MSHR* findMatch(Addr addr, int asid) const;
+
+    /**
+     * Find and return all the matching MSHRs in the provided vector.
+     * @param addr The address to find.
+     * @param asid The address space ID.
+     * @param matches The vector to return pointers to the matching MSHRs.
+     * @return True if any matches are found, false otherwise.
+     * @todo Typedef the vector??
+     */
+    bool findMatches(Addr addr, int asid, std::vector<MSHR*>& matches) const;
+
+    /**
+     * Find any pending requests that overlap the given request.
+     * @param req The request to find.
+     * @return A pointer to the earliest matching MSHR.
+     */
+    MSHR* findPending(Packet * &pkt) const;
+
+    /**
+     * Allocates a new MSHR for the request and size. This places the request
+     * as the first target in the MSHR.
+     * @param req The request to handle.
+     * @param size The number in bytes to fetch from memory.
+     * @return The a pointer to the MSHR allocated.
+     *
+     * @pre There are free MSHRs.
+     */
+    MSHR* allocate(Packet * &pkt, int size = 0);
+
+    /**
+     * Allocate a read request for the given address, and places the given
+     * target on the target list.
+     * @param addr The address to fetch.
+     * @param asid The address space for the fetch.
+     * @param size The number of bytes to request.
+     * @param target The first target for the request.
+     * @return Pointer to the new MSHR.
+     */
+    MSHR* allocateFetch(Addr addr, int asid, int size, Packet * &target);
+
+    /**
+     * Allocate a target list for the given address.
+     * @param addr The address to fetch.
+     * @param asid The address space for the fetch.
+     * @param size The number of bytes to request.
+     * @return Pointer to the new MSHR.
+     */
+    MSHR* allocateTargetList(Addr addr, int asid, int size);
+
+    /**
+     * Removes the given MSHR from the queue. This places the MSHR on the
+     * free list.
+     * @param mshr
+     */
+    void deallocate(MSHR* mshr);
+
+    /**
+     * Allocates a target to the given MSHR. Used to keep track of the number
+     * of outstanding targets.
+     * @param mshr The MSHR to allocate the target to.
+     * @param req The target request.
+     */
+    void allocateTarget(MSHR* mshr, Packet * &pkt)
+    {
+        mshr->allocateTarget(pkt);
+        allocatedTargets += 1;
+    }
+
+    /**
+     * Remove a MSHR from the queue. Returns an iterator into the allocatedList
+     * for faster squash implementation.
+     * @param mshr The MSHR to remove.
+     * @return An iterator to the next entry in the allocatedList.
+     */
+    MSHR::Iterator deallocateOne(MSHR* mshr);
+
+    /**
+     * Moves the MSHR to the front of the pending list if it is not in service.
+     * @param mshr The mshr to move.
+     */
+    void moveToFront(MSHR *mshr);
+
+    /**
+     * Mark the given MSHR as in service. This removes the MSHR from the
+     * pendingList. Deallocates the MSHR if it does not expect a response.
+     * @param mshr The MSHR to mark in service.
+     */
+    void markInService(MSHR* mshr);
+
+    /**
+     * Mark an in service mshr as pending, used to resend a request.
+     * @param mshr The MSHR to resend.
+     * @param cmd The command to resend.
+     */
+    void markPending(MSHR* mshr, Packet::Command cmd);
+
+    /**
+     * Squash outstanding requests with the given thread number. If a request
+     * is in service, just squashes the targets.
+     * @param req->getThreadNum()ber The thread to squash.
+     */
+    void squash(int threadNum);
+
+    /**
+     * Returns true if the pending list is not empty.
+     * @return True if there are outstanding requests.
+     */
+    bool havePending() const
+    {
+        return !pendingList.empty();
+    }
+
+    /**
+     * Returns true if there are no free MSHRs.
+     * @return True if this queue is full.
+     */
+    bool isFull() const
+    {
+        return (allocated > numMSHRs - numReserve);
+    }
+
+    /**
+     * Returns the request at the head of the pendingList.
+     * @return The next request to service.
+     */
+    Packet * getReq() const
+    {
+        if (pendingList.empty()) {
+            return NULL;
+        }
+        MSHR* mshr = pendingList.front();
+        return mshr->pkt;
+    }
+
+    /**
+     * Returns the number of outstanding targets.
+     * @return the number of allocated targets.
+     */
+    int getAllocatedTargets() const
+    {
+        return allocatedTargets;
+    }
+
+};
+
+#endif //__MSHR_QUEUE_HH__