physical.cc

来自「M5,一个功能强大的多处理器系统模拟器.很多针对处理器架构,性能的研究都使用它作」· CC 代码 · 共 557 行 · 第 1/2 页

    } else if (pkt->isRead()) {
        assert(!pkt->isWrite());
        if (pkt->isLocked()) {
            trackLoadLocked(pkt);
        }
        memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
        TRACE_PACKET("Read");
    } else if (pkt->isWrite()) {
        if (writeOK(pkt)) {
            memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
            TRACE_PACKET("Write");
        }
    } else if (pkt->isInvalidate()) {
        //upgrade or invalidate
        if (pkt->needsResponse()) {
            pkt->makeAtomicResponse();
        }
    } else {
        panic("unimplemented");
    }

    if (pkt->needsResponse()) {
        pkt->makeAtomicResponse();
    }
    return calculateLatency(pkt);
}


void
PhysicalMemory::doFunctionalAccess(PacketPtr pkt)
{
    assert(pkt->getAddr() >= start() &&
           pkt->getAddr() + pkt->getSize() <= start() + size());


    uint8_t *hostAddr = pmemAddr + pkt->getAddr() - start();

    if (pkt->isRead()) {
        memcpy(pkt->getPtr<uint8_t>(), hostAddr, pkt->getSize());
        TRACE_PACKET("Read");
        pkt->makeAtomicResponse();
    } else if (pkt->isWrite()) {
        memcpy(hostAddr, pkt->getPtr<uint8_t>(), pkt->getSize());
        TRACE_PACKET("Write");
        pkt->makeAtomicResponse();
    } else if (pkt->isPrint()) {
        Packet::PrintReqState *prs =
            dynamic_cast<Packet::PrintReqState*>(pkt->senderState);
        // Need to call printLabels() explicitly since we're not going
        // through printObj().
        prs->printLabels();
        // Right now we just print the single byte at the specified address.
        ccprintf(prs->os, "%s%#x\n", prs->curPrefix(), *hostAddr);
    } else {
        panic("PhysicalMemory: unimplemented functional command %s",
              pkt->cmdString());
    }
}


Port *
PhysicalMemory::getPort(const std::string &if_name, int idx)
{
    // Accept request for "functional" port for backwards compatibility
    // with places where this function is called from C++.  I'd prefer
    // to move all these into Python someday.
    if (if_name == "functional") {
        return new MemoryPort(csprintf("%s-functional", name()), this);
    }

    if (if_name != "port") {
        panic("PhysicalMemory::getPort: unknown port %s requested", if_name);
    }

    if (idx >= ports.size()) {
        ports.resize(idx+1);
    }

    if (ports[idx] != NULL) {
        panic("PhysicalMemory::getPort: port %d already assigned", idx);
    }

    MemoryPort *port =
        new MemoryPort(csprintf("%s-port%d", name(), idx), this);

    ports[idx] = port;
    return port;
}


void
PhysicalMemory::recvStatusChange(Port::Status status)
{
}

PhysicalMemory::MemoryPort::MemoryPort(const std::string &_name,
                                       PhysicalMemory *_memory)
    : SimpleTimingPort(_name), memory(_memory)
{ }

void
PhysicalMemory::MemoryPort::recvStatusChange(Port::Status status)
{
    memory->recvStatusChange(status);
}

void
PhysicalMemory::MemoryPort::getDeviceAddressRanges(AddrRangeList &resp,
                                                   bool &snoop)
{
    memory->getAddressRanges(resp, snoop);
}

void
PhysicalMemory::getAddressRanges(AddrRangeList &resp, bool &snoop)
{
    snoop = false;
    resp.clear();
    resp.push_back(RangeSize(start(), params()->range.size()));
}

int
PhysicalMemory::MemoryPort::deviceBlockSize()
{
    return memory->deviceBlockSize();
}

Tick
PhysicalMemory::MemoryPort::recvAtomic(PacketPtr pkt)
{
    return memory->doAtomicAccess(pkt);
}

void
PhysicalMemory::MemoryPort::recvFunctional(PacketPtr pkt)
{
    pkt->pushLabel(memory->name());

    if (!checkFunctional(pkt)) {
        // Default implementation of SimpleTimingPort::recvFunctional()
        // calls recvAtomic() and throws away the latency; we can save a
        // little here by just not calculating the latency.
        memory->doFunctionalAccess(pkt);
    }

    pkt->popLabel();
}

unsigned int
PhysicalMemory::drain(Event *de)
{
    int count = 0;
    for (PortIterator pi = ports.begin(); pi != ports.end(); ++pi) {
        count += (*pi)->drain(de);
    }

    if (count)
        changeState(Draining);
    else
        changeState(Drained);
    return count;
}

void
PhysicalMemory::serialize(ostream &os)
{
    gzFile compressedMem;
    string filename = name() + ".physmem";

    SERIALIZE_SCALAR(filename);

    // write memory file
    string thefile = Checkpoint::dir() + "/" + filename.c_str();
    int fd = creat(thefile.c_str(), 0664);
    if (fd < 0) {
        perror("creat");
        fatal("Can't open physical memory checkpoint file '%s'\n", filename);
    }

    compressedMem = gzdopen(fd, "wb");
    if (compressedMem == NULL)
        fatal("Insufficient memory to allocate compression state for %s\n",
                filename);

    if (gzwrite(compressedMem, pmemAddr, params()->range.size()) !=
        params()->range.size()) {
        fatal("Write failed on physical memory checkpoint file '%s'\n",
              filename);
    }

    if (gzclose(compressedMem))
        fatal("Close failed on physical memory checkpoint file '%s'\n",
              filename);
}

void
PhysicalMemory::unserialize(Checkpoint *cp, const string &section)
{
    gzFile compressedMem;
    long *tempPage;
    long *pmem_current;
    uint64_t curSize;
    uint32_t bytesRead;
    const int chunkSize = 16384;


    string filename;

    UNSERIALIZE_SCALAR(filename);

    filename = cp->cptDir + "/" + filename;

    // mmap memoryfile
    int fd = open(filename.c_str(), O_RDONLY);
    if (fd < 0) {
        perror("open");
        fatal("Can't open physical memory checkpoint file '%s'", filename);
    }

    compressedMem = gzdopen(fd, "rb");
    if (compressedMem == NULL)
        fatal("Insufficient memory to allocate compression state for %s\n",
                filename);

    // unmap file that was mmaped in the constructor
    // This is done here to make sure that gzip and open don't muck with our
    // nice large space of memory before we reallocate it
    munmap((char*)pmemAddr, params()->range.size());

    pmemAddr = (uint8_t *)mmap(NULL, params()->range.size(),
        PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);

    if (pmemAddr == (void *)MAP_FAILED) {
        perror("mmap");
        fatal("Could not mmap physical memory!\n");
    }

    curSize = 0;
    tempPage = (long*)malloc(chunkSize);
    if (tempPage == NULL)
        fatal("Unable to malloc memory to read file %s\n", filename);

    /* Only copy bytes that are non-zero, so we don't give the VM system hell */
    while (curSize < params()->range.size()) {
        bytesRead = gzread(compressedMem, tempPage, chunkSize);
        if (bytesRead != chunkSize &&
            bytesRead != params()->range.size() - curSize)
            fatal("Read failed on physical memory checkpoint file '%s'"
                  " got %d bytes, expected %d or %d bytes\n",
                  filename, bytesRead, chunkSize,
                  params()->range.size() - curSize);

        assert(bytesRead % sizeof(long) == 0);

        for (int x = 0; x < bytesRead/sizeof(long); x++)
        {
             if (*(tempPage+x) != 0) {
                 pmem_current = (long*)(pmemAddr + curSize + x * sizeof(long));
                 *pmem_current = *(tempPage+x);
             }
        }
        curSize += bytesRead;
    }

    free(tempPage);

    if (gzclose(compressedMem))
        fatal("Close failed on physical memory checkpoint file '%s'\n",
              filename);

}

PhysicalMemory *
PhysicalMemoryParams::create()
{
    return new PhysicalMemory(this);
}