Added core for segregated list

master
TuDatTr 2021-01-24 16:35:51 +01:00
parent 7a20a7dd86
commit 2a4dd8d48d
1 changed files with 53 additions and 17 deletions

70
mm.c
View File

@ -34,6 +34,7 @@ team_t team = {
/* Second member's email address (leave blank if none) */ /* Second member's email address (leave blank if none) */
"tuan-dat.tran@stud.uni-due.de" "tuan-dat.tran@stud.uni-due.de"
}; };
//////////////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////// STRUCTURE ////////////////////////////////// /////////////////////////////////// STRUCTURE //////////////////////////////////
//////////////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////////////////////
@ -43,7 +44,7 @@ team_t team = {
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// HEADER | SIZE | A| // HEADER | SIZE | A|
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// BODY | ALLOCED MEMORY | // BP-> | ALLOCED MEMORY |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// FOOTER | SIZE | A| // FOOTER | SIZE | A|
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
@ -53,11 +54,11 @@ team_t team = {
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// HEADER | SIZE | A| // HEADER | SIZE | A|
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | PTR TO PREV FREE BLK | // BP-> | PTR TO PREV FREE BLK |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | PTR TO NEXT FREE BLK | // | PTR TO NEXT FREE BLK |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// BODY | UNALLOC MEMORY | // | UNALLOC MEMORY |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// FOOTER | SIZE | A| // FOOTER | SIZE | A|
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
@ -80,6 +81,7 @@ team_t team = {
#define CHUNKSIZE (1<<12) /* Extend heap by this amount (bytes) */ #define CHUNKSIZE (1<<12) /* Extend heap by this amount (bytes) */
#define MAX(x, y) ((x) > (y)? (x) : (y)) #define MAX(x, y) ((x) > (y)? (x) : (y))
#define MIN(x, y) ((x) < (y)? (x) : (y))
/* Pack a size and allocated bit into a word */ /* Pack a size and allocated bit into a word */
#define PACK(size, alloc) ((size) | (alloc)) #define PACK(size, alloc) ((size) | (alloc))
@ -100,12 +102,17 @@ team_t team = {
#define NEXT_BLKP(bp) ((char *)(bp) + GET_SIZE(((char *)(bp) - WSIZE))) #define NEXT_BLKP(bp) ((char *)(bp) + GET_SIZE(((char *)(bp) - WSIZE)))
#define PREV_BLKP(bp) ((char *)(bp) - GET_SIZE(((char *)(bp) - DSIZE))) #define PREV_BLKP(bp) ((char *)(bp) - GET_SIZE(((char *)(bp) - DSIZE)))
#define PUT_PTR(p, ptr) (*(unsigned int *)(p) = (unsigned int)(ptr))
#define PRV_FREE(bp) ((char *)(bp))
#define NXT_FREE(bp) ((char *)(bp) + WSIZE)
//////////////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////////////////////
////////////////////////////////// STATIC VARS ///////////////////////////////// ////////////////////////////////// STATIC VARS /////////////////////////////////
//////////////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////////////////////
const size_t LIST_SIZE = 100; const size_t LISTSIZE = 11;
static char* heap_listp; static char* heap_listp;
static char* seg_list[LIST_SIZE]; char* seg_list[LISTSIZE];
//////////////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////////////////////
///////////////////////////////// HELPER PREDEF //////////////////////////////// ///////////////////////////////// HELPER PREDEF ////////////////////////////////
@ -138,23 +145,42 @@ static void place(void *bp, size_t asize)
PUT(FTRP(bp), PACK(csize, 1)); PUT(FTRP(bp), PACK(csize, 1));
} }
} }
static void* first_fit(size_t asize) {
/* First fit search */
void *bp;
for (bp = heap_listp; GET_SIZE(HDRP(bp)) > 0; bp = NEXT_BLKP(bp)) { static int getSzClass(size_t asize) {
if (!GET_ALLOC(HDRP(bp)) && (asize <= GET_SIZE(HDRP(bp)))) { for (size_t i = 0; i < LISTSIZE; ++i) {
return bp; if (asize == (1 << i)) {
return i;
} }
} }
return NULL; /* No fit */ return LISTSIZE;
} }
static void* best_fit(void* ptr, size_t asize) {
unsigned long left_over = GET_SIZE(ptr) - asize;
int c = 0;
while (NXT_FREE(ptr) != NULL) {
left_over = (MIN(left_over, GET_SIZE(ptr) - asize));
ptr = NXT_FREE(ptr);
}
return NULL;
}
/* Page 856, Pearson R. Bryant D. OHallaron. Computer Systems: A Programmers Perspective.3rd Edition, Pearson, 2003. */ /* Page 856, Pearson R. Bryant D. OHallaron. Computer Systems: A Programmers Perspective.3rd Edition, Pearson, 2003. */
static void* find_fit(size_t asize) static void* find_fit(size_t asize)
{ {
return first_fit(asize); int szClass = getSzClass(asize);
void* classPtr = seg_list[szClass];
if (classPtr == NULL) {
return NULL;
} else {
if (szClass != LISTSIZE -1) {
while (NXT_FREE(classPtr) != NULL) {
classPtr = NXT_FREE(classPtr);
}
return classPtr;
} else {
return best_fit(classPtr, asize);
}
}
} }
/* Page 833, Pearson R. Bryant D. OHallaron. Computer Systems: A Programmers Perspective.3rd Edition, Pearson, 2003. */ /* Page 833, Pearson R. Bryant D. OHallaron. Computer Systems: A Programmers Perspective.3rd Edition, Pearson, 2003. */
@ -190,6 +216,10 @@ static void *extend_heap(size_t words)
char *bp; char *bp;
size_t size; size_t size;
if (words == 0) {
return NULL;
}
/* Allocate an even number of words to maintain alignment */ /* Allocate an even number of words to maintain alignment */
size = (words % 2) ? (words+1) * WSIZE : words * WSIZE; size = (words % 2) ? (words+1) * WSIZE : words * WSIZE;
if ((long)(bp = mem_sbrk(size)) == -1) if ((long)(bp = mem_sbrk(size)) == -1)
@ -200,6 +230,9 @@ static void *extend_heap(size_t words)
PUT(FTRP(bp), PACK(size,0)); /* Free block footer */ PUT(FTRP(bp), PACK(size,0)); /* Free block footer */
PUT(HDRP(NEXT_BLKP(bp)), PACK(0, 1)); /* New epilogue header */ PUT(HDRP(NEXT_BLKP(bp)), PACK(0, 1)); /* New epilogue header */
PUT_PTR(PRV_FREE(bp), 0);
PUT_PTR(NXT_FREE(bp), 0);
/* Coalesce if the previous block was free */ /* Coalesce if the previous block was free */
return coalesce(bp); return coalesce(bp);
} }
@ -213,9 +246,11 @@ static void *extend_heap(size_t words)
*/ */
int mm_init(void) int mm_init(void)
{ {
for (size_t i = 0; i < LIST_SIZE; ++i) { // init seg_list
for (size_t i = 0; i < LISTSIZE; ++i) {
seg_list[i] = NULL; seg_list[i] = NULL;
} }
/* Create the initial empty heap */ /* Create the initial empty heap */
if ((heap_listp = mem_sbrk(4*WSIZE)) == (void *)-1) if ((heap_listp = mem_sbrk(4*WSIZE)) == (void *)-1)
return -1; return -1;
@ -250,7 +285,7 @@ void *mm_malloc(size_t size)
if (size <= DSIZE) if (size <= DSIZE)
asize = 2*DSIZE; asize = 2*DSIZE;
else else
asize = DSIZE * ((size + (DSIZE) + (DSIZE-1)) / DSIZE); asize = ALIGN(size+DSIZE);
/* Search the free list for a fit */ /* Search the free list for a fit */
if ((bp = find_fit(asize)) != NULL) { if ((bp = find_fit(asize)) != NULL) {
@ -272,9 +307,10 @@ void *mm_malloc(size_t size)
*/ */
void mm_free(void *ptr) void mm_free(void *ptr)
{ {
size_t size= GET_SIZE(HDRP(ptr)); size_t size = GET_SIZE(HDRP(ptr));
PUT(HDRP(ptr), PACK(size, 0)); PUT(HDRP(ptr), PACK(size, 0));
PUT(FTRP(ptr), PACK(size, 0)); PUT(FTRP(ptr), PACK(size, 0));
coalesce(ptr); coalesce(ptr);
} }