gem5/src/cpu/thread_context.cc

/*
 * Copyright (c) 2012 ARM Limited
 * All rights reserved
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
 * unmodified and in its entirety in all distributions of the software,
 * modified or unmodified, in source code or in binary form.
 *
 * Copyright (c) 2006 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: Kevin Lim
 */

#include "base/misc.hh"
#include "base/trace.hh"
#include "config/the_isa.hh"
#include "cpu/base.hh"
#include "cpu/quiesce_event.hh"
#include "cpu/thread_context.hh"
#include "debug/Context.hh"
#include "sim/full_system.hh"

void
ThreadContext::compare(ThreadContext *one, ThreadContext *two)
{
    DPRINTF(Context, "Comparing thread contexts\n");

    // First loop through the integer registers.
    for (int i = 0; i < TheISA::NumIntRegs; ++i) {
        TheISA::IntReg t1 = one->readIntReg(i);
        TheISA::IntReg t2 = two->readIntReg(i);
        if (t1 != t2)
            panic("Int reg idx %d doesn't match, one: %#x, two: %#x",
                  i, t1, t2);
    }

    // Then loop through the floating point registers.
    for (int i = 0; i < TheISA::NumFloatRegs; ++i) {
        TheISA::FloatRegBits t1 = one->readFloatRegBits(i);
        TheISA::FloatRegBits t2 = two->readFloatRegBits(i);
        if (t1 != t2)
            panic("Float reg idx %d doesn't match, one: %#x, two: %#x",
                  i, t1, t2);
    }
    for (int i = 0; i < TheISA::NumMiscRegs; ++i) {
        TheISA::MiscReg t1 = one->readMiscRegNoEffect(i);
        TheISA::MiscReg t2 = two->readMiscRegNoEffect(i);
        if (t1 != t2)
            panic("Misc reg idx %d doesn't match, one: %#x, two: %#x",
                  i, t1, t2);
    }

    if (!(one->pcState() == two->pcState()))
        panic("PC state doesn't match.");
    int id1 = one->cpuId();
    int id2 = two->cpuId();
    if (id1 != id2)
        panic("CPU ids don't match, one: %d, two: %d", id1, id2);

    id1 = one->contextId();
    id2 = two->contextId();
    if (id1 != id2)
        panic("Context ids don't match, one: %d, two: %d", id1, id2);


}

void
serialize(ThreadContext &tc, std::ostream &os)
{
    using namespace TheISA;

    FloatRegBits floatRegs[NumFloatRegs];
    for (int i = 0; i < NumFloatRegs; ++i)
        floatRegs[i] = tc.readFloatRegBitsFlat(i);
    // This is a bit ugly, but needed to maintain backwards
    // compatibility.
    arrayParamOut(os, "floatRegs.i", floatRegs, NumFloatRegs);

    IntReg intRegs[NumIntRegs];
    for (int i = 0; i < NumIntRegs; ++i)
        intRegs[i] = tc.readIntRegFlat(i);
    SERIALIZE_ARRAY(intRegs, NumIntRegs);

    tc.pcState().serialize(os);

    // thread_num and cpu_id are deterministic from the config
}

void
unserialize(ThreadContext &tc, Checkpoint *cp, const std::string &section)
{
    using namespace TheISA;

    FloatRegBits floatRegs[NumFloatRegs];
    // This is a bit ugly, but needed to maintain backwards
    // compatibility.
    arrayParamIn(cp, section, "floatRegs.i", floatRegs, NumFloatRegs);
    for (int i = 0; i < NumFloatRegs; ++i)
        tc.setFloatRegBitsFlat(i, floatRegs[i]);

    IntReg intRegs[NumIntRegs];
    UNSERIALIZE_ARRAY(intRegs, NumIntRegs);
    for (int i = 0; i < NumIntRegs; ++i)
        tc.setIntRegFlat(i, intRegs[i]);

    PCState pcState;
    pcState.unserialize(cp, section);
    tc.pcState(pcState);

    // thread_num and cpu_id are deterministic from the config
}

void
takeOverFrom(ThreadContext &ntc, ThreadContext &otc)
{
    assert(ntc.getProcessPtr() == otc.getProcessPtr());

    ntc.setStatus(otc.status());
    ntc.copyArchRegs(&otc);
    ntc.setContextId(otc.contextId());
    ntc.setThreadId(otc.threadId());

    if (FullSystem) {
        assert(ntc.getSystemPtr() == otc.getSystemPtr());

        BaseCPU *ncpu(ntc.getCpuPtr());
        assert(ncpu);
        EndQuiesceEvent *oqe(otc.getQuiesceEvent());
        assert(oqe);
        assert(oqe->tc == &otc);

        BaseCPU *ocpu(otc.getCpuPtr());
        assert(ocpu);
        EndQuiesceEvent *nqe(ntc.getQuiesceEvent());
        assert(nqe);
        assert(nqe->tc == &ntc);

        if (oqe->scheduled()) {
            ncpu->schedule(nqe, oqe->when());
            ocpu->deschedule(oqe);
        }
    }

    otc.setStatus(ThreadContext::Halted);
}