xref: /gem5/src/mem/cache/write_queue.cc

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 * licensed hereunder.  You may use the software subject to the license
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 * Copyright (c) 2003-2005 The Regents of The University of Michigan
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * Authors: Erik Hallnor
 *          Andreas Sandberg
 *          Andreas Hansson
 */

/** @file
 * Definition of WriteQueue class functions.
 */

#include "mem/cache/write_queue.hh"

using namespace std;

WriteQueue::WriteQueue(const std::string &_label,
                       int num_entries, int reserve)
    : Queue<WriteQueueEntry>(_label, num_entries, reserve)
{}

WriteQueueEntry *
WriteQueue::allocate(Addr blk_addr, unsigned blk_size, PacketPtr pkt,
                    Tick when_ready, Counter order)
{
    assert(!freeList.empty());
    WriteQueueEntry *entry = freeList.front();
    assert(entry->getNumTargets() == 0);
    freeList.pop_front();

    entry->allocate(blk_addr, blk_size, pkt, when_ready, order);
    entry->allocIter = allocatedList.insert(allocatedList.end(), entry);
    entry->readyIter = addToReadyList(entry);

    allocated += 1;
    return entry;
}

void
WriteQueue::markInService(WriteQueueEntry *entry)
{
    if (!entry->isUncacheable()) {
        // a normal eviction, such as a writeback or a clean evict, no
        // more to do as we are done from the perspective of this
        // cache
        entry->popTarget();
        deallocate(entry);
    } else {
        // uncacheable write, and we will eventually receive a
        // response
        entry->markInService();
        readyList.erase(entry->readyIter);
        _numInService += 1;
    }
}