src/mem/ruby/common/Consumer.cc

/*
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 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
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 *
 * Copyright (c) 2012 Mark D. Hill and David A. Wood
 * All rights reserved.
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 * 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;
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#include "mem/ruby/common/Consumer.hh"

namespace gem5
{

namespace ruby
{

Consumer::Consumer(ClockedObject *_em)
    : m_wakeup_event([this]{ processCurrentEvent(); },
                    "Consumer Event", false),
      em(_em)
{ }

void
Consumer::scheduleEvent(Cycles timeDelta)
{
    m_wakeup_ticks.insert(em->clockEdge(timeDelta));
    scheduleNextWakeup();
}

void
Consumer::scheduleEventAbsolute(Tick evt_time)
{
    m_wakeup_ticks.insert(
        divCeil(evt_time, em->clockPeriod()) * em->clockPeriod());
    scheduleNextWakeup();
}

void
Consumer::scheduleNextWakeup()
{
    // look for the next tick in the future to schedule
    auto it = m_wakeup_ticks.lower_bound(em->clockEdge());
    if (it != m_wakeup_ticks.end()) {
        Tick when = *it;
        assert(when >= em->clockEdge());
        if (m_wakeup_event.scheduled() && (when < m_wakeup_event.when()))
            em->reschedule(m_wakeup_event, when, true);
        else if (!m_wakeup_event.scheduled())
            em->schedule(m_wakeup_event, when);
    }
}

void
Consumer::processCurrentEvent()
{
    auto curr = m_wakeup_ticks.begin();
    assert(em->clockEdge() == *curr);

    // remove the current tick from the wakeup list, wake up, and then schedule
    // the next wakeup
    m_wakeup_ticks.erase(curr);
    wakeup();
    scheduleNextWakeup();
}

} // namespace ruby
} // namespace gem5