//----------------------------------------------------------------------
//
// ProcessFreeResources
//
// Free the resources associated with a process. This assumes the
// process isn't currently on any queue.
//
//----------------------------------------------------------------------
void ProcessFreeResources (PCB *pcb) {
int i = 0;
int usrsp = MEM_ADDRESS_TO_PAGE(pcb->currentSavedFrame[PROCESS_STACK_USER_STACKPOINTER]);
// Allocate a new link for this pcb on the freepcbs queue
if ((pcb->l = AQueueAllocLink(pcb)) == NULL) {
printf("FATAL ERROR: could not get Queue Link in ProcessFreeResources!\n");
exitsim();
}
// Set the pcb's status to available
pcb->flags = PROCESS_STATUS_FREE;
// Insert the link into the freepcbs queue
if (AQueueInsertLast(&freepcbs, pcb->l) != QUEUE_SUCCESS) {
printf("FATAL ERROR: could not insert PCB link into freepcbs queue in ProcessFreeResources!\n");
exitsim();
}
//------------------------------------------------------------
// STUDENT: Free any memory resources on process death here.
//------------------------------------------------------------
for(i = 0; i < 5; i++) {
MemoryFreePte(pcb->pagetable[i]);
}
for(i = usrsp; i <= MEM_ADDRESS_TO_PAGE(MEM_MAX_VIRTUAL_ADDRESS); i++) {
MemoryFreePte(pcb->pagetable[i]);
}
MemoryFreePage (pcb->sysStackArea / MEM_PAGESIZE);
ProcessSetStatus (pcb, PROCESS_STATUS_FREE);
dbprintf ('p', "ProcessFreeResources: function complete\n");
}
//----------------------------------------------------------------------
//
// ProcessFreeResources
//
// Free the resources associated with a process. This assumes the
// process isn't currently on any queue.
//
//----------------------------------------------------------------------
void ProcessFreeResources (PCB *pcb) {
int i = 0;
dbprintf ('p', "ProcessFreeResources: function started\n");
// Allocate a new link for this pcb on the freepcbs queue
if ((pcb->l = AQueueAllocLink(pcb)) == NULL) {
printf("FATAL ERROR: could not get Queue Link in ProcessFreeResources!\n");
GracefulExit();
}
// Set the pcb's status to available
pcb->flags = PROCESS_STATUS_FREE;
// Insert the link into the freepcbs queue
if (AQueueInsertLast(&freepcbs, pcb->l) != QUEUE_SUCCESS) {
printf("FATAL ERROR: could not insert PCB link into freepcbs queue in ProcessFreeResources!\n");
GracefulExit();
}
// Free the process's memory.
for (i = 0; i < pcb->npages; i++) {
MemoryFreePte (pcb->pagetable[i]);
}
// Free the page allocated for the system stack
MemoryFreePage (pcb->sysStackArea / MEMORY_PAGE_SIZE);
ProcessSetStatus (pcb, PROCESS_STATUS_FREE);
dbprintf ('p', "ProcessFreeResources: function complete\n");
}
//----------------------------------------------------------------------
//
// ProcessFreeResources
//
// Free the resources associated with a process. This assumes the
// process isn't currently on any queue.
//
//----------------------------------------------------------------------
void
ProcessFreeResources (PCB *pcb)
{
int i;
int npages;
QueueInsertLast (&freepcbs, &pcb->l);
// Free the process's memory. This is easy with a one-level page
// table, but could get more complex with two-level page tables.
npages = pcb->npages;
for (i=0; i<npages; i++)
{
MemoryFreeSharedPte(pcb, i); // *MUST* be called before calling
// MemoryFreePte. MemoryFreePte does not know
// anything about shared pages, and hence it
// might screw up big time
}
for (i = 0; i < pcb->npages; i++) {
MemoryFreePte (pcb->pagetable[i]);
}
// Free the page allocated for the system stack
MemoryFreePage (pcb->sysStackArea / MEMORY_PAGE_SIZE);
ProcessSetStatus (pcb, PROCESS_STATUS_FREE);
}
//----------------------------------------------------------------------
//
// ProcessFreeResources
//
// Free the resources associated with a process. This assumes the
// process isn't currently on any queue.
//
//----------------------------------------------------------------------
void
ProcessFreeResources (PCB *pcb)
{
int i;
int npages;
QueueInsertLast (&freepcbs, &pcb->l);
// Free the process's memory. This is easy with a one-level page
// table, but could get more complex with two-level page tables.
//------------------------------------------
// You may change the code below
//------------------------------------------
npages = pcb->npages;
for (i = 0; i < pcb->npages; i++) {
MemoryFreePte (pcb->pagetable[i]);
}
// Free the page allocated for the system stack
MemoryFreePage (pcb->sysStackArea / MEMORY_PAGE_SIZE);
ProcessSetStatus (pcb, PROCESS_STATUS_FREE);
}
