process.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 719 行 · 第 1/2 页

    else{
        //OPEN standard in and seek to the right location
        stdin_fd = Process::openInputFile(in);
        if (lseek(stdin_fd, fdo_stdin->fileOffset, SEEK_SET) < 0)
            panic("Unable to seek to correct location in file: %s", in);
    }

    if (out == "stdout" || out == "cout")
        stdout_fd = STDOUT_FILENO;
    else if (out == "stderr" || out == "cerr")
        stdout_fd = STDERR_FILENO;
    else if (out == "None")
        stdout_fd = -1;
    else{
        stdout_fd = Process::openOutputFile(out);
        if (lseek(stdin_fd, fdo_stdout->fileOffset, SEEK_SET) < 0)
            panic("Unable to seek to correct in file: %s", out);
    }

    stderr_fd = (stdout_fd != STDOUT_FILENO) ? stdout_fd : STDERR_FILENO;

    fdo_stdin->fd = stdin_fd;
    fdo_stdout->fd = stdout_fd;
    fdo_stderr->fd = stderr_fd;


    for (int free_fd = 3; free_fd <= MAX_FD; ++free_fd) {
        Process::FdMap *fdo = &fd_map[free_fd];
        if (fdo->fd != -1) {
            if (fdo->isPipe){
                if (fdo->filename == "PIPE-WRITE")
                    continue;
                else {
                    assert (fdo->filename == "PIPE-READ");
                    //create a new pipe
                    int fds[2];
                    int pipe_retval = pipe(fds);

                    if (pipe_retval < 0) {
                        // error
                        panic("Unable to create new pipe.");
                    }
                    fdo->fd = fds[0]; //set read pipe
                    Process::FdMap *fdo_write = &fd_map[fdo->readPipeSource];
                    if (fdo_write->filename != "PIPE-WRITE")
                        panic ("Couldn't find write end of the pipe");

                    fdo_write->fd = fds[1];//set write pipe
               }
            } else {
                //Open file
                int fd = open(fdo->filename.c_str(), fdo->flags, fdo->mode);

                if (fd == -1)
                    panic("Unable to open file: %s", fdo->filename);
                fdo->fd = fd;

                //Seek to correct location before checkpoint
                if (lseek(fd,fdo->fileOffset, SEEK_SET) < 0)
                    panic("Unable to seek to correct location in file: %s", fdo->filename);
            }
        }
    }
}
void
Process::find_file_offsets(){
    for (int free_fd = 0; free_fd <= MAX_FD; ++free_fd) {
        Process::FdMap *fdo = &fd_map[free_fd];
        if (fdo->fd != -1) {
            fdo->fileOffset = lseek(fdo->fd, 0, SEEK_CUR);
        }  else {
                fdo->filename = "NULL";
                fdo->fileOffset = 0;
        }
    }
}

void
Process::setReadPipeSource(int read_pipe_fd, int source_fd){
    Process::FdMap *fdo = &fd_map[read_pipe_fd];
    fdo->readPipeSource = source_fd;
}

void
Process::FdMap::serialize(std::ostream &os)
{
    SERIALIZE_SCALAR(fd);
    SERIALIZE_SCALAR(isPipe);
    SERIALIZE_SCALAR(filename);
    SERIALIZE_SCALAR(flags);
    SERIALIZE_SCALAR(readPipeSource);
    SERIALIZE_SCALAR(fileOffset);
}

void
Process::FdMap::unserialize(Checkpoint *cp, const std::string &section)
{
    UNSERIALIZE_SCALAR(fd);
    UNSERIALIZE_SCALAR(isPipe);
    UNSERIALIZE_SCALAR(filename);
    UNSERIALIZE_SCALAR(flags);
    UNSERIALIZE_SCALAR(readPipeSource);
    UNSERIALIZE_SCALAR(fileOffset);
}

void
Process::serialize(std::ostream &os)
{
    SERIALIZE_SCALAR(initialContextLoaded);
    SERIALIZE_SCALAR(brk_point);
    SERIALIZE_SCALAR(stack_base);
    SERIALIZE_SCALAR(stack_size);
    SERIALIZE_SCALAR(stack_min);
    SERIALIZE_SCALAR(next_thread_stack_base);
    SERIALIZE_SCALAR(mmap_start);
    SERIALIZE_SCALAR(mmap_end);
    SERIALIZE_SCALAR(nxm_start);
    SERIALIZE_SCALAR(nxm_end);
    find_file_offsets();
    pTable->serialize(os);
    for (int x = 0; x <= MAX_FD; x++) {
        nameOut(os, csprintf("%s.FdMap%d", name(), x));
        fd_map[x].serialize(os);
    }

}

void
Process::unserialize(Checkpoint *cp, const std::string &section)
{
    UNSERIALIZE_SCALAR(initialContextLoaded);
    UNSERIALIZE_SCALAR(brk_point);
    UNSERIALIZE_SCALAR(stack_base);
    UNSERIALIZE_SCALAR(stack_size);
    UNSERIALIZE_SCALAR(stack_min);
    UNSERIALIZE_SCALAR(next_thread_stack_base);
    UNSERIALIZE_SCALAR(mmap_start);
    UNSERIALIZE_SCALAR(mmap_end);
    UNSERIALIZE_SCALAR(nxm_start);
    UNSERIALIZE_SCALAR(nxm_end);
    pTable->unserialize(cp, section);
    for (int x = 0; x <= MAX_FD; x++) {
        fd_map[x].unserialize(cp, csprintf("%s.FdMap%d", section, x));
     }
    fix_file_offsets();
    
    checkpointRestored = true;

}


////////////////////////////////////////////////////////////////////////
//
// LiveProcess member definitions
//
////////////////////////////////////////////////////////////////////////


LiveProcess::LiveProcess(LiveProcessParams * params, ObjectFile *_objFile)
    : Process(params), objFile(_objFile),
      argv(params->cmd), envp(params->env), cwd(params->cwd)
{
    __uid = params->uid;
    __euid = params->euid;
    __gid = params->gid;
    __egid = params->egid;
    __pid = params->pid;
    __ppid = params->ppid;

    prog_fname = params->cmd[0];

    // load up symbols, if any... these may be used for debugging or
    // profiling.
    if (!debugSymbolTable) {
        debugSymbolTable = new SymbolTable();
        if (!objFile->loadGlobalSymbols(debugSymbolTable) ||
            !objFile->loadLocalSymbols(debugSymbolTable)) {
            // didn't load any symbols
            delete debugSymbolTable;
            debugSymbolTable = NULL;
        }
    }
}

void
LiveProcess::argsInit(int intSize, int pageSize)
{
    Process::startup();

    // load object file into target memory
    objFile->loadSections(initVirtMem);

    // Calculate how much space we need for arg & env arrays.
    int argv_array_size = intSize * (argv.size() + 1);
    int envp_array_size = intSize * (envp.size() + 1);
    int arg_data_size = 0;
    for (int i = 0; i < argv.size(); ++i) {
        arg_data_size += argv[i].size() + 1;
    }
    int env_data_size = 0;
    for (int i = 0; i < envp.size(); ++i) {
        env_data_size += envp[i].size() + 1;
    }

    int space_needed =
        argv_array_size + envp_array_size + arg_data_size + env_data_size;
    if (space_needed < 32*1024)
        space_needed = 32*1024;

    // set bottom of stack
    stack_min = stack_base - space_needed;
    // align it
    stack_min = roundDown(stack_min, pageSize);
    stack_size = stack_base - stack_min;
    // map memory
    pTable->allocate(stack_min, roundUp(stack_size, pageSize));

    // map out initial stack contents
    Addr argv_array_base = stack_min + intSize; // room for argc
    Addr envp_array_base = argv_array_base + argv_array_size;
    Addr arg_data_base = envp_array_base + envp_array_size;
    Addr env_data_base = arg_data_base + arg_data_size;

    // write contents to stack
    uint64_t argc = argv.size();
    if (intSize == 8)
        argc = htog((uint64_t)argc);
    else if (intSize == 4)
        argc = htog((uint32_t)argc);
    else
        panic("Unknown int size");

    initVirtMem->writeBlob(stack_min, (uint8_t*)&argc, intSize);

    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);

    assert(NumArgumentRegs >= 2);
    threadContexts[0]->setIntReg(ArgumentReg[0], argc);
    threadContexts[0]->setIntReg(ArgumentReg[1], argv_array_base);
    threadContexts[0]->setIntReg(StackPointerReg, stack_min);

    Addr prog_entry = objFile->entryPoint();
    threadContexts[0]->setPC(prog_entry);
    threadContexts[0]->setNextPC(prog_entry + sizeof(MachInst));

#if THE_ISA != ALPHA_ISA //e.g. MIPS or Sparc
    threadContexts[0]->setNextNPC(prog_entry + (2 * sizeof(MachInst)));
#endif

    num_processes++;
}

void
LiveProcess::syscall(int64_t callnum, ThreadContext *tc)
{
    num_syscalls++;

    SyscallDesc *desc = getDesc(callnum);
    if (desc == NULL)
        fatal("Syscall %d out of range", callnum);

    desc->doSyscall(callnum, this, tc);
}

LiveProcess *
LiveProcess::create(LiveProcessParams * params)
{
    LiveProcess *process = NULL;

    string executable =
        params->executable == "" ? params->cmd[0] : params->executable;
    ObjectFile *objFile = createObjectFile(executable);
    if (objFile == NULL) {
        fatal("Can't load object file %s", executable);
    }

    if (objFile->isDynamic())
       fatal("Object file is a dynamic executable however only static "
             "executables are supported!\n       Please recompile your "
             "executable as a static binary and try again.\n");

#if THE_ISA == ALPHA_ISA
    if (objFile->hasTLS())
        fatal("Object file has a TLS section and single threaded TLS is not\n"
              "       currently supported for Alpha! Please recompile your "
              "executable with \n       a non-TLS toolchain.\n");

    if (objFile->getArch() != ObjectFile::Alpha)
        fatal("Object file architecture does not match compiled ISA (Alpha).");
    switch (objFile->getOpSys()) {
      case ObjectFile::Tru64:
        process = new AlphaTru64Process(params, objFile);
        break;

      case ObjectFile::Linux:
        process = new AlphaLinuxProcess(params, objFile);
        break;

      default:
        fatal("Unknown/unsupported operating system.");
    }
#elif THE_ISA == SPARC_ISA
    if (objFile->getArch() != ObjectFile::SPARC64 && objFile->getArch() != ObjectFile::SPARC32)
        fatal("Object file architecture does not match compiled ISA (SPARC).");
    switch (objFile->getOpSys()) {
      case ObjectFile::Linux:
        if (objFile->getArch() == ObjectFile::SPARC64) {
            process = new Sparc64LinuxProcess(params, objFile);
        } else {
            process = new Sparc32LinuxProcess(params, objFile);
        }
        break;


      case ObjectFile::Solaris:
        process = new SparcSolarisProcess(params, objFile);
        break;
      default:
        fatal("Unknown/unsupported operating system.");
    }
#elif THE_ISA == MIPS_ISA
    if (objFile->getArch() != ObjectFile::Mips)
        fatal("Object file architecture does not match compiled ISA (MIPS).");
    switch (objFile->getOpSys()) {
      case ObjectFile::Linux:
        process = new MipsLinuxProcess(params, objFile);
        break;

      default:
        fatal("Unknown/unsupported operating system.");
    }
#elif THE_ISA == ARM_ISA
    if (objFile->getArch() != ObjectFile::Arm)
        fatal("Object file architecture does not match compiled ISA (ARM).");
    switch (objFile->getOpSys()) {
      case ObjectFile::Linux:
        process = new ArmLinuxProcess(params, objFile);
        break;

      default:
        fatal("Unknown/unsupported operating system.");
    }
#else
#error "THE_ISA not set"
#endif


    if (process == NULL)
        fatal("Unknown error creating process object.");
    return process;
}

LiveProcess *
LiveProcessParams::create()
{
    return LiveProcess::create(this);
}