void swapOutFrame(int entry1Index)
{
// clear the definition bit in entry 1 probably just set entry 1 to 0
int entry1, entry2;
entry1 = memory[entry1Index];
entry2 = memory[entry1Index + 1];
// if dirty bit is not set and swap exists we are done
if (DIRTY(entry1) && PAGED(entry2)) {
DEBUG_STATEMENT(DEBUG_MMU,"\nDirty copy of swap write to old page");
// if swap exits swap access page with old write
accessPage(SWAPPAGE(entry2), FRAME(entry1), PAGE_OLD_WRITE);
} else if (!PAGED(entry2)) {
DEBUG_STATEMENT(DEBUG_MMU,"\nNo copy in swap write to new swap");
// if swap doesn't exist then we need to write out to an new write
memory[entry1Index + 1] = entry2 = SET_PAGED(nextPage);
accessPage(nextPage, FRAME(entry1), PAGE_NEW_WRITE);
}
if (DEBUG_MMU) { outPTE("\nSwapped Entry - (Pre-clear) ", entry1Index); }
memory[entry1Index] = 0;
if (DEBUG_MMU) { outPTE("Swapped Entry - ", entry1Index); }
return;
}
// **************************************************************************
// **************************************************************************
// output page table entry
void outPTE(char* s, int pte)
{
int pte1, pte2;
char flags[10];
// read pt
pte1 = memory[pte];
pte2 = memory[pte+1];
// look at appropriate flags
strcpy(flags, "-----");
if (DEFINED(pte1)) flags[0] = 'F';
if (DIRTY(pte1)) flags[1] = 'D';
if (REFERENCED(pte1)) flags[2] = 'R';
if (PINNED(pte1)) flags[3] = 'P';
if (PAGED(pte2)) flags[4] = 'S';
// output pte line
if(DEFINED(pte1) || DEFINED(pte2))
printf("\n%s x%04x = %04x %04x %s", s, pte, pte1, pte2, flags);
if (DEFINED(pte1) || DEFINED(pte2)) printf(" Frame=%d", FRAME(pte1));
if (DEFINED(pte2)) printf(" Page=%d", SWAPPAGE(pte2));
return;
} // end outPTE
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
memAccess += 2;
// rpta = 0x2400 + RPTI(va);
rpta = tcb[curTask].RPT + RPTI(va);
rpte1 = memory[rpta];
rpte2 = memory[rpta+1];
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
if (DEFINED(rpte1))
{
// printf("\nUPT frame already defined");
// defined
memHits++;
}
else
{
// fault
memPageFaults++;
rptFrame = getFrame(-1);
rpte1 = SET_DEFINED(rptFrame);
if (PAGED(rpte2))
{
//upt is in swap and we need to read it back in
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
}
else
{
//initialize the upt memory
memset(&memory[(rptFrame<<6)], 0, 128);
}
}
memory[rpta] = rpte1 = SET_REF(rpte1);
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
if (DEFINED(upte1))
{
// defined
memHits++;
}
else
{
// fault
memPageFaults++;
uptFrame = getFrame(FRAME(memory[rpta]));
memory[rpta] = rpte1 = SET_REF(SET_DIRTY(rpte1));
upte1 = SET_DEFINED(uptFrame);
if (PAGED(upte2))
{
//get the data frame from swap
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
}
else
{
//we don't need to do anything
//but we could initialize the mem to 0xf025 which is lc-3 halt instruction
memset(&memory[(uptFrame<<6)], 0xf025, 128);
}
}
if (rwFlg) {
upte1 = SET_DIRTY(upte1);
}
memory[upta] = SET_REF(upte1);
memory[upta+1] = upte2;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
return &memory[va];
#endif
} // end getMemAdr
int getFrame(int notme)
{
int UPTClock; // clock for UPT
int frame;
frame = getAvailableFrame();
if (frame >=0) return frame;
if(RPTClock == 0){
RPTClock = LC3_RPT;
}
int RPTBegin = RPTClock;
int first = 1;
int rptCount = 0;
//iterate the first time through the tables
while(first || RPTClock != RPTBegin){
rptCount++;
first = 0;
//Check and make sure the notme condition holds
if(DEFINED(memory[RPTClock])){
UPTClock = (FRAME(memory[RPTClock])<<6);
int UPTBegin = UPTClock;
int uFirst = 1;
int hadDefined = 0;
int uptcount = 0;
while(uFirst || UPTClock != UPTBegin){
uptcount++;
uFirst = 0;
if(DEFINED(memory[UPTClock])){
hadDefined = 1;
}
if(notme != UPTClock && DEFINED(memory[UPTClock])){
//swap out if not referenced
if(!REFERENCED(memory[UPTClock])){
//if it's dirty, write it to memory
int swapPage = 0;
if (DIRTY(memory[UPTClock])){
if(PAGED(memory[UPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[UPTClock + 1]), FRAME(memory[UPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[UPTClock]), PAGE_NEW_WRITE);
memory[UPTClock] = CLEAR_DIRTY(memory[UPTClock]);
memory[UPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
}
//no longer in main memory--it's swapped!
memory[UPTClock] = CLEAR_DEFINED(memory[UPTClock]);
//increment the clock
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(memory[UPTClock]);
}
memory[UPTClock] = CLEAR_REF(memory[UPTClock]);
}
//sanity check
assert(UPTClock >= 0x3000);
if(UPTClock + 2 < UPTBegin + LC3_FRAME_SIZE)
UPTClock += 2;
else
UPTClock = UPTBegin;
}
if(!REFERENCED(memory[RPTClock]) && !hadDefined && notme != RPTClock){
int swapPage;
if(PAGED(memory[RPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[RPTClock + 1]), FRAME(memory[RPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[RPTClock]), PAGE_NEW_WRITE);
memory[RPTClock] = CLEAR_DIRTY(memory[RPTClock]);
memory[RPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
memory[RPTClock] = CLEAR_DEFINED(memory[RPTClock]);
int rE1 = memory[RPTClock];
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(rE1);
}
//clear the reference bit
memory[RPTClock] = CLEAR_REF(memory[RPTClock]);
}
if(RPTClock + 2 < LC3_RPT_END){
RPTClock += 2;
}
else{
RPTClock = LC3_RPT;
}
}
RPTBegin = RPTClock;
first = 1;
while(first || RPTClock != RPTBegin){
rptCount++;
first = 0;
//Check and make sure the notme condition holds
if(DEFINED(memory[RPTClock])){
UPTClock = (FRAME(memory[RPTClock])<<6);
int UPTBegin = UPTClock;
int uFirst = 1;
int hadDefined = 0;
int uptcount = 0;
while(uFirst || UPTClock != UPTBegin){
uptcount++;
uFirst = 0;
if(DEFINED(memory[UPTClock])){
hadDefined = 1;
}
if(notme != UPTClock && DEFINED(memory[UPTClock])){
//swap out if not referenced
if(!REFERENCED(memory[UPTClock])){
//if it's dirty, write it to memory
int swapPage = 0;
if (DIRTY(memory[UPTClock])){
if(PAGED(memory[UPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[UPTClock + 1]), FRAME(memory[UPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[UPTClock]), PAGE_NEW_WRITE);
memory[UPTClock] = CLEAR_DIRTY(memory[UPTClock]);
memory[UPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
}
//no longer in main memory--it's swapped!
memory[UPTClock] = CLEAR_DEFINED(memory[UPTClock]);
//increment the clock
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(memory[UPTClock]);
}
memory[UPTClock] = CLEAR_REF(memory[UPTClock]);
}
//sanity check
assert(UPTClock >= 0x3000);
if(UPTClock + 2 < UPTBegin + LC3_FRAME_SIZE)
UPTClock += 2;
else
UPTClock = UPTBegin;
}
if(!REFERENCED(memory[RPTClock]) && !hadDefined && notme != RPTClock){
int swapPage;
if(PAGED(memory[RPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[RPTClock + 1]), FRAME(memory[RPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[RPTClock]), PAGE_NEW_WRITE);
memory[RPTClock] = CLEAR_DIRTY(memory[RPTClock]);
memory[RPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
memory[RPTClock] = CLEAR_DEFINED(memory[RPTClock]);
int rE1 = memory[RPTClock];
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(rE1);
}
//clear the reference bit
memory[RPTClock] = CLEAR_REF(memory[RPTClock]);
}
if(RPTClock + 2 < LC3_RPT_END){
RPTClock += 2;
}
else{
RPTClock = LC3_RPT;
}
}
//we should never ever be here
assert(0);
return -1;
}
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
rpta = tcb[curTask].RPT + RPTI(va);
rpte1 = memory[rpta];
rpte2 = memory[rpta+1];
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
if (DEFINED(rpte1))
{
memHits++;
}
else
{
// fault
memPageFaults++;
rptFrame = getFrame(-1);
assert(rptFrame >= 192);
rpte1 = SET_DEFINED(rptFrame);
if (PAGED(rpte2))
{
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
pageReads++;
}
else
{
rpte1 = SET_DIRTY(rpte1); rpte2 = 0;
memset(&memory[(rptFrame<<6)], 0, 128);
}
}
memory[rpta] = rpte1 = SET_REF(rpte1);
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
if (DEFINED(upte1))
{
memHits++;
}
else
{
// fault
memPageFaults++;
uptFrame = getFrame(FRAME(memory[rpta]));
assert(uptFrame >= 192);
upte1 = SET_DEFINED(uptFrame);
if (PAGED(upte2))
{
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
pageReads++;
}
else
{
upte1 = SET_DIRTY(upte1); upte2 = 0;
}
}
if(rwFlg != 0){
upte1 = SET_DIRTY(upte1);
}
memory[upta] = SET_REF(upte1);
memory[upta+1] = upte2;
memAccess = memHits + memPageFaults;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
pa = va;
#endif
return &memory[pa];
} // end getMemAdr
int clockRunner(int notme)
{
//extern int curRPT;
//extern TCB tcb[MAX_TASKS];
int i,j,k;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int victimFrame;
int tupta, tupte1;
//printf("\nClock running...%d\n",clockCount++);
//victimEntry = 0;
while (1)
{
//rpta = tcb[curRPT].RPT;
for (i = curRPTE; i < 0x3000; i+=2)
{
//rpte1 = memory[rpta + i];
//rpte2 = memory[rpta + i + 1];
rpte1 = memory[i];
rpte2 = memory[i + 1];
if (DEFINED(rpte1))
{
if (curUPTE == 0)
{
if(PINNED(rpte1))
{
//memory[rpta + i] = rpte1 = CLEAR_PINNED(rpte1);
memory[i] = rpte1 = CLEAR_PINNED(rpte1);
}
}
upta = (FRAME(rpte1)<<6);
for (j = curUPTE; j < 64; j+=2)
{
upte1 = memory[upta + j];
upte2 = memory[upta + j + 1];
if (DEFINED(upte1))
{
//memory[rpta + i] = rpte1 = SET_PINNED(rpte1);
memory[i] = rpte1 = SET_PINNED(rpte1);
if (REFERENCED(upte1))
{
memory[upta + j] = upte1 = CLEAR_REF(upte1);
}
else
{
//victimEntry = upte1;
// if end of UPT, reset upte and move to next UPT
//break; // because this is the victim
// instead of break, do swapping and return victim frame number
// immunity from notme
//if (FRAME(upte1) != notme)
//{
if (DIRTY(upte1))
{
int page;
//stat
pageWrites++;
if(PAGED(upte2))
{
page = accessPage(SWAPPAGE(upte2),FRAME(upte1),PAGE_OLD_WRITE);
}
else
{
page = accessPage(0,FRAME(upte1),PAGE_NEW_WRITE);
}
upte2 = page;
memory[upta + j + 1] = upte2 = SET_PAGED(upte2);
}
// save frame number before obliterating first word
victimFrame = FRAME(upte1);
//memory[upta + j] = upte1 = CLEAR_DEFINED(upte1);
memory[upta + j] = upte1 = 0;
curUPTE = (j + 2) % 64;
//printf("\nChose a UPT victim: %d\n",victimFrame);
return victimFrame;
//}
}
}
}
// immunity from notme
if ((FRAME(rpte1) != notme) && (!PINNED(rpte1)))
{
//victimEntry = rpte1;
// if end of RPT, reset rpte and move to next RPT
//break; // because this is the victim
// instead of break, do swapping and return victim frame number
//victimEntry = FRAME(rpte1);
// sanity check
tupta = (FRAME(rpte1)<<6);
for (k = 0; k < 64; k+=2)
{
tupte1 = memory[tupta + k];
if (DEFINED(tupte1))
printf("\nEvicting a UPT that has defined entries!!!\n");
}
//if (DIRTY(rpte1))
{
int page;
//stat
pageWrites++;
if(PAGED(rpte2))
{
page = accessPage(SWAPPAGE(rpte2),FRAME(rpte1),PAGE_OLD_WRITE);
}
else
{
page = accessPage(0,FRAME(rpte1),PAGE_NEW_WRITE);
}
rpte2 = page;
//memory[rpta + i + 1] = rpte2 = SET_PAGED(rpte2);
memory[i + 1] = rpte2 = SET_PAGED(rpte2);
}
// save frame number before obliterating first word
victimFrame = FRAME(rpte1);
//memory[rpta + i] = rpte1 = CLEAR_DEFINED(rpte1);
//memory[rpta + i] = rpte1 = 0;
memory[i] = rpte1 = 0;
//curRPTE = (i + 2) % 64;
//printf("\nChose a RPT victim: %d\n",victimFrame);
return victimFrame;
}
curUPTE = 0;
}
}
//curRPT = (curRPT + 1) % MAX_TASKS;
curRPTE = 0x2400;
}
}
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
extern TCB tcb[MAX_TASKS];
extern int curTask;
//stat
memAccess++;
rpta = tcb[curTask].RPT + RPTI(va); // 0x2400 + RPTI(va);
rpte1 = memory[rpta];
rpte2 = memory[rpta+1];
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
if (DEFINED(rpte1))
{
// defined
//stat
memHits++;
if (rwFlg)
rpte1 = SET_DIRTY(rpte1);
}
else
{
// fault
//stat
memPageFaults++;
rptFrame = getFrame(-1);
rpte1 = SET_DEFINED(rptFrame);
if (PAGED(rpte2))
{
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
//stat
pageReads++;
//clean
if (rwFlg)
rpte1 = SET_DIRTY(rpte1);
else
rpte1 = CLEAR_DIRTY(rpte1);
}
else
{
memset(&memory[(rptFrame<<6)], 0, 128);
//dirty
rpte1 = SET_DIRTY(rpte1);
}
}
rpte1 = SET_PINNED(rpte1);
memory[rpta] = rpte1 = SET_REF(rpte1);
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
//stat
memAccess++;
if (DEFINED(upte1))
{
// defined
//stat
memHits++;
if (rwFlg)
upte1 = SET_DIRTY(upte1);
}
else
{
// fault
//stat
memPageFaults++;
uptFrame = getFrame(FRAME(memory[rpta]));
upte1 = SET_DEFINED(uptFrame);
if (PAGED(upte2))
{
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
//stat
pageReads++;
//clean unless being written to
if (rwFlg)
upte1 = SET_DIRTY(upte1);
else
upte1 = CLEAR_DIRTY(upte1);
}
else
{
//dirty
upte1 = SET_DIRTY(upte1);
}
}
rpte1 = SET_PINNED(rpte1);
memory[rpta] = rpte1;
memory[upta] = upte1 = SET_REF(upte1);
memory[upta+1] = upte2;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
return &memory[va];
#endif
} // end getMemAdr
int getFrame(int notme)
{
int frame;
frame = getAvailableFrame();
if (frame >=0) return frame;
// run clock
int i, j, upta, frameToRemove;
i = lastRpte;
// i = 0x2400;
// j = lastUpte;
while(1){
// for(i=0x2400;i<0x3000;i+=2){
// printf("%x", i);
if(DEFINED(memory[i])){
upta = FRAME(memory[i]);
upta = (upta<<6);
//double confirm
int k;
bool nothingInFrame = 1;
for(k=upta;k<upta+64;k+=2){
if(DEFINED(memory[k])){
nothingInFrame = 0;
break;
}
}
if(nothingInFrame && FRAME(memory[i])!=notme){
frameToRemove = FRAME(memory[i]);
lastRpte=i+2;
memory[i] = CLEAR_DEFINED(memory[i]);
memory[i] = CLEAR_REF(memory[i]);
if(PAGED(memory[i+1]) && DIRTY(memory[i])){
memory[i+1] = accessPage(SWAPPAGE(memory[i+1]), frameToRemove, PAGE_OLD_WRITE);
}else{
memory[i+1] = accessPage(0, frameToRemove, PAGE_NEW_WRITE);
}
memory[i+1] = SET_PAGED(memory[i+1]);
memory[i] = SET_DIRTY(memory[i]);
//possibly clear frame number
return frameToRemove;
// i can swap out this upt
}
// for(j=upta;j<upta+64;j+=2){
while(uptOffset < 64){
j = upta + uptOffset;
if(DEFINED(memory[j])){
if(REFERENCED(memory[j])){
memory[j] = CLEAR_REF(memory[j]);
}else{
//use this data frame
frameToRemove = FRAME(memory[j]);
lastRpte = i;
memory[j] = CLEAR_DEFINED(memory[j]);
memory[j] = CLEAR_REF(memory[j]);
// memory[j] = SWAPPAGE(memory[j]);
if(PAGED(memory[j+1]) && DIRTY(memory[j])){
memory[j+1] = accessPage(SWAPPAGE(memory[j+1]), frameToRemove, PAGE_OLD_WRITE);
}else{
memory[j+1] = accessPage(0, frameToRemove, PAGE_NEW_WRITE);
}
memory[j+1] = SET_PAGED(memory[j+1]);
uptOffset+=2; // may not need this line
//need to loop through rest next time but if nothing dont remove this one
return frameToRemove;
}
}
uptOffset+=2;
}
uptOffset = 0;
// }
}
i+=2;
if(i==0x3000){
i=0x2400;
}
// }
}
// memory[(frameToRemove<<6)]
return frame;
}
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
rpta = 0x2400 + RPTI(va) + 0x40*curTask; // address of the root page table
rpte1 = memory[rpta]; // get a word
rpte2 = memory[rpta+1]; // get another word
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
// printf("using memory Management\n");
if (DEFINED(rpte1))
{
memHits++;
// defined
}
else
{
memPageFaults++;
// fault
rptFrame = getFrame(-1);
rpte1 = SET_DEFINED(rptFrame); // setting the frame bit in the user page table
rpte1 = SET_DIRTY(rpte1);
if (PAGED(rpte2)) // it exists in swap space
{
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
}
else
{
memset(&memory[(rptFrame<<6)], 0, 128); //sets 128 bytes to 0 why is it 128? why bitshift by 6?
}
}
memory[rpta] = rpte1 = SET_REF(rpte1); // sets the referenced bit in the root page table
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
if (DEFINED(upte1))
{
memHits++;
// defined
}
else
{
memPageFaults++;
// fault
uptFrame = getFrame(FRAME(memory[rpta]));
upte1 = SET_DEFINED(uptFrame);
upte1 = SET_DIRTY(upte1);
if (PAGED(upte2))
{
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
}
else
{
memset(&memory[(uptFrame<<6)], 0, 128); //sets 128 bytes to 0 why is it 128? why bitshift by 6?
}
}
if(rwFlg){
memory[rpta] = SET_DIRTY(memory[rpta]);
}else{
}
memory[upta] = SET_REF(upte1);
memory[upta+1] = upte2;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
return &memory[va];
#endif
} // end getMemAdr