// Ends the process
private void EndProcess()
{
// Deallocate the memory
MMU.DeallocateMemory(activeProgram);
// Adds the pcb to the terminated queue
activeProgram.Core_Used = ID;
// Remove the program from the running queue
Driver._QueueLock.Wait();
var pcb = activeProgram;
Queue.Running.Remove(pcb);
Queue.Terminated.AddLast(pcb);
Driver._QueueLock.Release();
// Clears the CPU & PCB attributes
this.registers = null;
this.activeProgram = null;
this.PC = 0;
this.OPCODE = -1;
this.isWaiting = false;
// Clear the cache
this.cache = null;
// Stop the running time
Metrics.Stop(pcb);
}
/// <summary>
/// Acquires the lock for the MMU then executes its write to functionality
/// --> Make async if MMU lock
/// </summary>
/// <returns>True if the memory was written</returns>
static void WriteToMemory(int allocationStartAddress)
{
Driver._MMULock.Wait();
var allProgramData = ReadFromDisk;
for (int i = 0; i < allProgramData.Length; i++)
{
MMU.WriteWord(allocationStartAddress + i, currentPointer, allProgramData[i]);
}
Driver._MMULock.Release();
}
/// <summary>
/// Does an IO instruction through the DMA
/// </summary>
/// <param name="readOrWrite">True for read, false for write</param>
/// <param name="callingCPU">The CPU that's calling the DMA</param>
/// <param name="reg1">Reg1 in the instructions</param>
/// <param name="secondLocation">The second location to be called, whether it be register or address</param>
/// <param name="reg2ORAddress">True for reg2, false for address as second location</param>
/// <returns></returns>
public static async Task IOExecution(bool readOrWrite, CPU callingCPU, int reg1, int secondLocation, bool reg2ORAddress)
{
/*
* Start the timer
*/
// Metrics.Stop(callingCPU.ActiveProgram);
if (readOrWrite) // ==> Read
{
Task thread = Task.Factory.StartNew(() =>
{
blocker().GetAwaiter().GetResult();
if (reg2ORAddress)
{
callingCPU.Registers[reg1] = callingCPU.Registers[secondLocation];
}
else
{
callingCPU.Registers[reg1] = MMU.ReadWord(secondLocation, callingCPU.ActiveProgram);
}
unlocker().GetAwaiter().GetResult();
});
thread.Wait();
}
else // ==> Write
{
Task thread = Task.Factory.StartNew(() =>
{
blocker().GetAwaiter().GetResult();
if (reg2ORAddress)
{
callingCPU.Registers[secondLocation] = callingCPU.Registers[reg1];
}
else
{
MMU.WriteWord(secondLocation, callingCPU.ActiveProgram, callingCPU.Registers[reg1]);
}
unlocker().GetAwaiter().GetResult();
});
thread.Wait();
}
/*
* Stop the waiting timer
*/
// Metrics.Stop(callingCPU.ActiveProgram);
// Increment the IO count for the pcb
callingCPU.ActiveProgram.IOOperationCount++;
}
/// <summary>
/// Loads the memory as long as the LT_Scheduler has the queue lock and memory has enough space
/// --> Make async
/// </summary>
public static void Execute()
{
// Acquires the lock for the new queue
__init();
// Multi core cpu configuration
if (Driver.IsMultiCPU)
{
// Sets the memory switch false to check if allocation is possible
bool isMemFullSwitch = false;
bool programsLoaded = false;
// While the memory is not full continue loading program data from disk to RAM with the MMU
while (!isMemFullSwitch && !programsLoaded)
{
// Allocate memory for the program disk instructions and buffer sizes if available
var allocationStartAddress = MMU.AllocateMemory(currentPointer);
// Validate if the MMU allocated memory in RAM for the program's instructions break if so
if (allocationStartAddress == -1)
{
isMemFullSwitch = true;
}
else
{
// Write the disk instructions and buffers to the allocated RAM for the PCB.ProgramSize count
WriteToMemory(allocationStartAddress);
SetPCBStartEndAddresses(allocationStartAddress);
// Move the pcb to the ready queue if it was loaded properly to memory
Queue.New.Remove(currentPointer);
Queue.Ready.AddLast(currentPointer);
if (Queue.New.First != null)
{
currentPointer = Queue.New.First.Value;
}
else
{
programsLoaded = true;
}
}
}
}
// Single core cpu configuration
else
{
// Allocate memory for the program disk instructions and buffer sizes if available
var allocationStartAddress = MMU.AllocateMemory(currentPointer);
// Validate if the MMU allocated memory in RAM for the program's instructions break if so
if (allocationStartAddress == -1)
{
throw new Exception("Long term scheduler could not load from disk to memory on single core configuration");
}
else
{
// Write the disk instructions and buffers to the allocated RAM for the PCB.ProgramSize count
WriteToMemory(allocationStartAddress);
SetPCBStartEndAddresses(allocationStartAddress);
// Move the pcb to the ready queue if it was loaded properly to memory
Queue.New.Remove(currentPointer);
Queue.Ready.AddLast(currentPointer);
}
}
}
private void ExecuteCondi()
{
string second;
int preAddr = addr;
addr /= 4;
if (dReg == 0)
{
second = Utilities.WordFill(Utilities.DecToHex(preAddr));
}
else
{
second = MMU.ReadWord(addr, activeProgram).Value;
}
switch (OPCODE)
{
case 2: // 02: ST
Driver._MMULock.Wait();
DMA.IOExecution(false, this, bReg, addr, false).GetAwaiter().GetResult();
Driver._MMULock.Release();
break;
case 3: // 03: LW
Driver._MMULock.Wait();
DMA.IOExecution(true, this, dReg, addr, false).GetAwaiter().GetResult();
Driver._MMULock.Release();
break;
case 11: // 0B: MOVI
registers[dReg].Value = Utilities.WordFill(second);
break;
case 12: // 0C: ADDI
registers[dReg] = registers[dReg] + MMU.ReadWord(addr, activeProgram);
break;
case 13: // 0D: MULI
registers[dReg] = registers[dReg] * MMU.ReadWord(addr, activeProgram);
break;
case 14: // 0E: DIVI
registers[dReg] = registers[dReg] / MMU.ReadWord(addr, activeProgram);
break;
case 15: // 0F: LDI
registers[dReg] = new Word(second);
break;
case 17: // 11: SLTI
registers[dReg].Value = Utilities.DecToHexFullAddr(registers[sReg0].ValueAsInt < addr ? 1 : 0);
break;
case 21: // 15: BEQ
PC = registers[bReg] == registers[dReg] ? preAddr : PC;
break;
case 22: // 16: BNE
PC = registers[bReg] != registers[dReg] ? preAddr : PC;
break;
case 23: // 17: BEZ
PC = registers[bReg].ValueAsInt == 0 ? preAddr : PC;
break;
case 24: // 18: BNZ
PC = registers[bReg].ValueAsInt != 0 ? preAddr : PC;
break;
case 25: // 19: BGZ
PC = registers[bReg].ValueAsInt > 0 ? preAddr : PC;
break;
case 26: // 1A: BLZ
PC = registers[bReg].ValueAsInt < 0 ? preAddr : PC;
break;
default:
throw new Exception("OPCode invalid, check the hex to dec conversion: " + OPCODE);
}
// Console.WriteLine($"CONDI: OPCODE {OPCODE} | B = {bReg} | D = {dReg} | ADDR = {addr} | SECOND = {second}");
}
string EffectiveAddress()
{
return(MMU.ReadWord(addr, this.activeProgram).Value);
}
