Ejemplo n.º 1
0
int getClockFrame(int notme)
{
    int frame;

    // iterate through rpts (0x2400 - LC3_RPT_END)
    int maxWrap = 20;
    for (;maxWrap; cBigHand += 2, cLittleHand = 0) {
        int i;
        int rpte1;
        int upta, upte1;

        if (cBigHand >= LC3_RPT_END) {
            DEBUG_STATEMENT(DEBUG_MMU,"\nClock is wrapping");
            cBigHand = LC3_RPT;
            maxWrap--;
        }

        rpte1 = memory[cBigHand];

        if (DEFINED(rpte1) && REFERENCED(rpte1)) {
            // clear reference
            DEBUG_STATEMENT(DEBUG_MMU,"\nclearing ref for rpte");
            memory[cBigHand] = rpte1 = CLEAR_REF(rpte1);
        } else if (DEFINED(rpte1)) { // if one is non-referenced go to the user page table
            // scout out the upt!! note that this has not been referenced
            if (DEBUG_MMU) { outPTE("\nRPT entry being checked - ", cBigHand); }
            upta = (FRAME(rpte1)<<6);

            for (i = cLittleHand % 64; i < 64;i += 2, cLittleHand = i % 64) { // - iterate over userpage table
                upte1 = memory[upta + (i)];
                if (PINNED(upte1) || FRAME(upte1) == notme) {
                    DEBUG_STATEMENT(DEBUG_MMU,"\nupte1 frame was the notme frame (%x = %x) or pinned", FRAME(upte1), notme);
                    if (DEBUG_MMU) { outPTE("UPT entry being checked - ", upta + i); }

                    continue;
                }

                if (DEFINED(upte1) && REFERENCED(upte1)) { // - if entry is referenced un-reference and move on
                    // clear reference
                    DEBUG_STATEMENT(DEBUG_MMU,"\nclearing ref for upte %d", cLittleHand);
                    memory[cBigHand] = rpte1 = SET_PINNED(rpte1);
                    memory[upta + (i)] = upte1 = CLEAR_REF(upte1);
                } else if (DEFINED(upte1)) { // - otherwise prep it for being put into swap
                    // we can use the frame referenced by upte1
                    if (DEBUG_MMU) { outPTE("UPT entry being checked - ", upta + 1); }
                    DEBUG_STATEMENT(DEBUG_MMU,"\nUpte1 %x, Upte2 %x", upte1, memory[upta + (i + 1)]);
                    memory[cBigHand] = rpte1 = SET_DIRTY(rpte1);
                    frame = FRAME(upte1);
                    swapOutFrame(upta + i);
                    cLittleHand += 2;
                    DEBUG_STATEMENT(DEBUG_MMU,"\nFound a data frame that can be used! (%d, %x)", frame, frame);

                    return frame;
                }
            }

            cLittleHand = 0;
            if (!REFERENCED(rpte1) && !PINNED(rpte1) && FRAME(rpte1) != notme) { // if we only replaced or did nothing to upte entries
                // we can use the frame referenced by rpte1
                frame = FRAME(rpte1);

                DEBUG_STATEMENT(DEBUG_MMU,"\nFound a upt frame that can be used! (%d, %x)", frame, frame);
                swapOutFrame(cBigHand);
                cBigHand += 2;
                return frame;
            } else { // otherwise remove the pin flag
                memory[cBigHand] = rpte1 = CLEAR_PINNED(rpte1);
            }

        }
    } // when you get the bottom start at the top again

    DEBUG_STATEMENT(DEBUG_MMU,"\n No valid frame found notme = %d", notme);
    if (DEBUG_MMU) {  displayTableHierarchy(); }

    return -1;
}
Ejemplo n.º 2
0
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;
	}


}
Ejemplo n.º 3
0
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;
}
Ejemplo n.º 4
0
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;
}