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kernel.cc

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// kernel.cc 
//      Initialization and cleanup routines for the Nachos kernel.
//
// Copyright (c) 1992-1996 The Regents of the University of California.
// All rights reserved.  See copyright.h for copyright notice and limitation 
// of liability and disclaimer of warranty provisions.

#include "copyright.h"
#include "debug.h"
#include "main.h"
#include "kernel.h"
#include "sysdep.h"
#include "synch.h"
#include "synchlist.h"
#include "libtest.h"
#include "elevatortest.h"
#include "string.h"

ThreadedKernel::ThreadedKernel(int argc, char **argv)
{
    randomSlice = FALSE; 
    for (int i = 1; i < argc; i++) {
        if (strcmp(argv[i], "-rs") == 0) {
            ASSERT(i + 1 < argc);
            RandomInit(atoi(argv[i + 1]));
            randomSlice = TRUE;
            i++;
        } else if (strcmp(argv[i], "-u") == 0) {
            cout << "Partial usage: nachos [-rs randomSeed]\n";
        }
    }
}

void
ThreadedKernel::Initialize()
{
    stats = new Statistics();           
    interrupt = new Interrupt;          
    scheduler = new Scheduler();        
    alarm = new Alarm(randomSlice);     

    // We didn't explicitly allocate the current thread we are running in.
    // But if it ever tries to give up the CPU, we better have a Thread
    // object to save its state. 
    currentThread = new Thread("main");         
    currentThread->setStatus(RUNNING);

    interrupt->Enable();
}

ThreadedKernel::~ThreadedKernel()
{
    delete alarm;
    delete scheduler;
    delete interrupt;
    delete stats;
    
    Exit(0);
}

void
ThreadedKernel::Run()
{
    // NOTE: if the procedure "main" returns, then the program "nachos"
    // will exit (as any other normal program would).  But there may be
    // other threads on the ready list (started in SelfTest).  
    // We switch to those threads by saying that the "main" thread 
    // is finished, preventing it from returning.
    currentThread->Finish();    
    // not reached
}

void
ThreadedKernel::SelfTest() {
   Semaphore *semaphore;
   SynchList<int> *synchList;
   
   LibSelfTest();               
   
   currentThread->SelfTest();   
   
                                
   semaphore = new Semaphore("test", 0);
   semaphore->SelfTest();      
   delete semaphore;
   
                                
   synchList = new SynchList<int>;
   synchList->SelfTest(9);      

   delete synchList;

   ElevatorSelfTest();
}

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