Add KR (not working) and Buddy MM (working)

Co-authored-by: Ezequiel Bellver <ebellver@itba.edu.ar>
Co-authored-by: Juan Barmasch <jbarmasch@itba.edu.ar>
This commit is contained in:
Santiago Lo Coco 2021-09-26 10:52:29 -03:00
parent c8eec8ee92
commit 3612e92eca
2 changed files with 627 additions and 7 deletions

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@ -1,13 +1,456 @@
#ifdef BUDDY
// #ifdef BUDDY
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>
#include <string.h>
#define MANAGED_MEMORY_SIZE 1024 * 1024 * 64
#include "memManager.h"
// https://github.com/sdpetrides/BuddyAllocator
char initMemoryManager(void *const restrict memoryForMemoryManager, void *const restrict managedMemory) {
return 1;
// char initMemoryManager(void *const restrict memoryForMemoryManager, void *const restrict managedMemory) {
// return 1;
// }
// void * memMalloc(const size_t memoryToAllocate) {
// return NULL;
// }
typedef struct meta {
unsigned char allo : 1; // 0000000_ - allocated
unsigned char left : 1; // 000000_0 - first or second
unsigned char size : 6; // ______00 - n where (2^n)-1 is the block size
} Meta;
static char myblock[MANAGED_MEMORY_SIZE];
void unpack(Meta * m, int pos);
/* Fills myblock with zeros and creates first metadata */
void init_block() {
memset(&myblock, '\0', MANAGED_MEMORY_SIZE);
memset(&myblock, 54, 1);
}
void * memMalloc(const size_t memoryToAllocate) {
return NULL;
/* Returns log base 2 of a double d */
double log2(double d) {
return log(d) / log(2);
}
#endif
/* Returns the level a reqSize will fit in */
int size_to_n(size_t reqSize) {
reqSize+=1;
double d = log2((double)reqSize);
return (int)ceil(d);
}
/* Returns the position of the next block of the correct size */
int jump_next(int n, int pos) {
int bits = pos>>(n);
bits+=1;
int ret = bits<<(n);
if (ret == MANAGED_MEMORY_SIZE) {
return ret;
} else {
return ret;
}
}
/* Returns the position of the left half of a pair */
int jump_back(int n, int pos) {
int bits = pos>>(n);
bits-=1;
return bits<<(n);
}
/* Fills a Meta struct with metadata at pos */
void unpack(Meta * m, int pos) {
memset(m, myblock[pos], 1);
}
/* Returns whether position at level n is left or right partner */
int is_left(int n, int pos) {
// Manipulate bits to set nth bit on
int k = 1;
k<<=(n);
// Manipulate bits to zero bits above n
unsigned int p = (unsigned int)pos;
p<<=(31-n);
p>>=(31-n);
if (k == p) {
return 0; // Right
} else {
return 1; // Left
}
}
/* Mergee two unallocated blocks with same size */
void merge(int pos, int pos2, int n) {
// Create new meta and set size field
char newMeta = (n+1)<<2;
// Set left field
if (is_left(n+1, pos)) {
newMeta+=2;
}
// Add new meta
myblock[pos] = newMeta;
// Delete meta on right partner
myblock[pos2] = 0;
}
/* MYmymalloc */
void * mymalloc(size_t reqSize) {
// Check if too big
if (reqSize > MANAGED_MEMORY_SIZE - 1) {
fprintf(stderr, "Error: Requested size too large\n");
}
// Traverse heap to find block of correct size - algo(n)
int n = size_to_n(reqSize);
int pos = 0;
unsigned char c = 0;
Meta * m = memset(&c, 0, 1);
while (pos < MANAGED_MEMORY_SIZE) {
// Read metadata
unpack(m, pos);
// Debugging
if (m->size == 0) {
exit(0);
}
if (n <= m->size) {
if (m->allo == 1) {
// Jump
pos = jump_next(n, pos);
continue;
} else if (m->size == n) {
// Allocate
myblock[pos]+=1;
pos+=1;
return (void*)((long int)&myblock+pos);
} else {
// Partition
// Get partner position
int partner = jump_next((m->size)-1, pos);
// Set Left
char meta_1 = 2;
char meta_2 = 0;
// Set Size
char s = ((m->size)-1)<<2;
meta_1 = (meta_1 | s);
meta_2 = (meta_2 | s);
// Fill in metadata
myblock[pos] = meta_1;
myblock[partner] = meta_2;
// Continue on same position with new size of block
continue;
}
} else {
// Jump
pos = jump_next(n, pos);
continue;
}
}
fprintf(stderr, "Error: Did not allocate %d\n", pos);
return 0;
}
/* MYmyfree */
void myfree(void * ptr) {
// Error Checking
if (ptr <= (void *)&myblock || ptr > (void *)(&myblock + MANAGED_MEMORY_SIZE)) {
fprintf(stderr, "Error en free\n");
return;
}
// Get position
// int pos = (int)(ptr-(void *)&myblock-1);
int pos = (int)((char *)ptr-(char *)&myblock-1);
// Check if valid metadata location
if (pos%2 == 1 || myblock[pos] == 0) {
fprintf(stderr, "Error con metadata\n");
return;
}
// Initialize variables for merge
unsigned char c1 = 0;
unsigned char c2 = 0;
Meta * m1 = memset(&c1, 0, 1);
Meta * m2 = memset(&c2, 0, 1);
unpack(m1,pos);
// Change allocated field
myblock[pos] = myblock[pos] - 1;
while (pos >= 0 && pos <= 8196){
// Read metadata
unpack(m1,pos);
if (m1->left) { // Left Partner
// Get position of other partner and read metadata
int pos2 = jump_next(m1->size, pos);
if (pos2 >= 0 && pos2 <= MANAGED_MEMORY_SIZE - 2) {
unpack(m2,pos2);
} else {
break;
}
// Merge or break
if (m2->allo || m2->size != m1->size) {
break;
} else {
merge(pos, pos2, m1->size);
}
} else { // Right Partner
// Get position of other partner and read metadata
int pos2 = jump_back(m2->size,pos);
if (pos2 >= 0 && pos2 <= MANAGED_MEMORY_SIZE -2) {
unpack(m2,pos2);
} else {
break;
}
// Merge or break
if (m2->allo || m2->size != m1->size) {
break;
} else {
merge(pos2, pos, m1->size);
}
}
}
}
int rando[20] = {
56, 73, 2, 8, 76,
56, 66, 21, 13, 4,
99, 80, 25, 6, 38,
10, 64, 12, 32, 71
};
/* testA: mymalloc() 1 byte 3000 times, then myfree() the 3000 1 byte pointers one by one */
void testA() {
int i = 0;
char * p[3000];
while (i < 3000) {
p[i] = (char *)mymalloc(sizeof(char)*1);
i++;
}
i = 0;
while (i < 3000) {
myfree(p[i]);
i++;
}
return;
}
/* testB: mymalloc() 1 byte and immediately myfree it 3000 times in a row */
void testB() {
int i = 0;
char * p;
while (i < 3000) {
p = (char *)mymalloc(sizeof(char)*1);
myfree(p);
i++;
}
return;
}
/* testC: Randomly choose between a 1 byte mymalloc() or myfree() 6000 times */
void testC() {
int i = 1;
int j = 0;
char * p[6000];
p[0] = (char *)mymalloc(sizeof(char)*1);
while (i+j < 1000) {
if ((i+j)%2 != 0) {
p[i] = (char *)mymalloc(sizeof(char)*1);
i++;
} else if (p[j] != 0) {
myfree(p[j]);
j++;
} else {
p[i] = (char *)mymalloc(sizeof(char)*1);
i++;
}
}
while (j <= i) {
myfree(p[j]);
j++;
}
return;
}
/* testD: Randomly choose between a randomly-sized mymalloc() or myfree 6000 times */
void testD() {
int i = 1;
int j = 0;
char * p[6000];
p[0] = (char *)mymalloc(sizeof(char)*(20));
while (i+j < 6000) {
if ((i+j)%2 != 0) {
p[i] = (char *)mymalloc(sizeof(char)*(((i%2)+1)*20));
i++;
} else if (p[j] != 0) {
myfree(p[j]);
j++;
} else {
p[i] = (char *)mymalloc(sizeof(char)*(((i%2)+1)*20));
i++;
}
}
while (j <= i) {
myfree(p[j]);
j++;
}
return;
}
/* testE: mymalloc 100 2bytes and myfrees 100 2bytes 10 times */
void testE() {
int i = 0;
int j = 0;
int k = 0;
int m = 0;
char * p[6000];
while (i < 6000) {
k = 0;
while (k < 100) {
p[i] = (char *)mymalloc(sizeof(char)*(2));
i++; k++;
}
m = 0;
while (m < 100) {
myfree(p[j]);
j++; m++;
}
}
return;
}
/* testF: mymalloc 2000 2bytes, myfrees 1000 2bytes, mymalloc 2000 2bytes, myfrees 3000 2bytes */
void testF() {
int i = 0;
int j = 0;
char * p[6000];
while (i < 2000) {
p[i] = (char *)mymalloc(sizeof(char)*(2));
i++;
}
while (j < 1000) {
myfree(p[j]);
j++;
}
while (i < 2000) {
p[i] = (char *)mymalloc(sizeof(char)*(2));
i++;
}
while (j < 4000) {
myfree(p[j]);
j++;
}
return;
}
int main(int argc, char const *argv[]) {
// Inititialize variables for workflow
int i, j;
// Loop through fptr array
for (j = 0; j < 6; j++) {
// Initialize time elapsed
double time_elapsed_in_seconds = 0.0;
// Run the fuction 100 times and calculate total time elapsed
for (i = 0; i < 100; i++) {
// Initialize myblock
init_block();
clock_t start = clock();
switch(j) {
case 0:
testA();
break;
case 1:
testB();
break;
case 2:
testC();
break;
case 3:
testD();
break;
case 4:
testE();
break;
case 5:
testF();
break;
}
clock_t end = clock();
time_elapsed_in_seconds+=(end - start)/(double)CLOCKS_PER_SEC;
}
// Print the after execution time of 100 runs
printf("Time Elapsed test%d: %f secs\n", j, time_elapsed_in_seconds/100);
}
return 0;
}
// #endif

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#ifndef BUDDY
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#include <string.h>
typedef long Align; /* for alignment to long boundary */
union header
{ /* block header */
struct
{
union header *ptr; /* next block if on free list */
unsigned size; /* size of this block */
} s;
Align x; /* force alignment of blocks */
};
typedef union header Header;
// static Header base; /* empty list to get started */
static Header *base; /* empty list to get started */
static Header *freep = NULL; /* start of free list */
char initMemoryManager(void * managedMemory) {
// freep = (Header *) managedMemory;
// freep->s.ptr = NULL;
// freep->s.size = ;
base = (Header *) managedMemory;
}
/* memMalloc: general-purpose storage allocator */
void *
memMalloc(unsigned nbytes)
{
Header *p, *prevp;
Header *moreroce(unsigned);
unsigned nunits;
// nunits = (nbytes + sizeof(Header) - 1) / sizeof(header) + 1;
nunits = (nbytes + sizeof(Header) - 1) / sizeof(Header) + 1;
if ((prevp = freep) == NULL)
{ /* no free list yet */
// base.s.ptr = freeptr = prevptr = &base;
// base.s.ptr = &base;
// base.s.size = 0;
base->s.ptr = base;
base->s.size = 0;
}
for (p = prevp->s.ptr;; prevp = p, p = p->s.ptr)
{
if (p->s.size >= nunits)
{ /* big enough */
if (p->s.size == nunits) /* exactly */
prevp->s.ptr = p->s.ptr;
else
{ /* allocate tail end */
p->s.size -= nunits;
p += p->s.size;
p->s.size = nunits;
}
freep = prevp;
return (void *)(p + 1);
}
// if (p == freep) /* wrapped around free list */
// if ((p = morecore(nunits)) == NULL)
// return NULL; /* none left */
}
}
// #define NALLOC 1024 /* minimum #units to request */
// /* morecore: ask system for more memory */
// static Header *morecore(unsigned nu)
// {
// char *cp, *sbrk(int);
// Header *up;
// if (nu < NALLOC)
// nu = NALLOC;
// cp = sbrk(nu * sizeof(Header));
// if (cp == (char *)-1) /* no space at all */
// return NULL;
// up = (Header *)cp;
// up->s.size = nu;
// free((void *)(up + 1));
// return freep;
// }
/* free: put block ap in free list */
void free(void *ap)
{
Header *bp, *p;
bp = (Header *)ap - 1; /* point to block header */
for (p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr)
if (p >= p->s.ptr && (bp > p || bp < p->s.ptr))
break; /* freed block at start or end of arena */
if (bp + bp->s.size == p->s.ptr)
{ /* join to upper nbr */
bp->s.size += p->s.ptr->s.size;
bp->s.ptr = p->s.ptr->s.ptr;
}
else
bp->s.ptr = p->s.ptr;
if (p + p->s.size == bp)
{ /* join to lower nbr */
p->s.size += bp->s.size;
p->s.ptr = bp->s.ptr;
}
else
p->s.ptr = bp;
freep = p;
}
char testOne() {
void * alloc1 = memMalloc(100);
void * alloc2 = memMalloc(200);
void * alloc3 = memMalloc(300);
memset(alloc1, 1, 100);
memset(alloc2, 2, 200);
memset(alloc3, 3, 300);
for (int i = 0; i < 600; i++) {
if (i < 100) {
assert(*((char *) alloc1+i) == 1);
} else if (i < 300) {
assert(*((char *) alloc1+i) == 2);
} else if (i < 600) {
assert(*((char *) alloc1+i) == 3);
}
}
return EXIT_SUCCESS;
}
static unsigned long int next = 1;
int rand(void) // RAND_MAX assumed to be 32767
{
next = next * 1103515245 + 12345;
return (unsigned int)(next/65536) % 32768;
}
/*
char testTwo() {
void * ptr;
while (ptr != NULL){
ptr = memMalloc((rand() % 2000) + 1);
if (!((char *) memoryManager->nextAddress >= memoryManager->initialAddress)) {
printStringLen(13, "allocRand1 -- ERROR", 31);
new_line();
return EXIT_FAILURE;
}
if (!((char *) memoryManager->nextAddress <= memoryManager->initialAddress + MANAGED_MEMORY_SIZE)) {
printStringLen(13, "allocRand2 -- ERROR", 31);
new_line();
return EXIT_FAILURE;
}
// if (!((char *) memoryManager->lastAddress >= memoryManager->initialAddress)) {
// }
// if (!((char *) memoryManager->lastAddress <= memoryManager->initialAddress + MANAGED_MEMORY_SIZE)) {
// }
}
return EXIT_SUCCESS;
}
*/
char mem[1024];
int main() {
initMemoryManager(mem);
if (testOne() == EXIT_FAILURE)
return EXIT_FAILURE;
// if (testTwo() == EXIT_FAILURE)
// return EXIT_FAILURE;
}
#endif