RingBufferBlock* RingBuffer::searchFreeBlock(int size)
{
int alignLength = ALIGN(sizeof(struct RingBufferBlock) + size);
int freeSpace = 0;
// 从head开始依次往后查找空闲block，直到拼接起来的空闲block长度大于传入的size
struct RingBufferBlock *block = getHead();
do {
// 如果该块当前仍在被使用，则中止搜索
if (block->m_link != NULL && block->m_length >= sizeof(struct RingBufferBlock)) {
return NULL;
}
freeSpace += ALIGN(block->m_length) + sizeof(RingBufferBlock);
// 检测长度是否已足够分配
if (freeSpace > alignLength + sizeof(RingBufferBlock)) {
// 将找到的这几块空闲block切割为2块block，并返回第一块block的地址
return splitBlock(freeSpace , size);
}
block = getNextBlock(block);
} while(block);
return NULL;
}
//versucht einen Speicherbereich mit <byteCount> vielen Bytes zu reservieren
//Falls dies nicht gelingt wird ein NULL (0) Pointer zurueckgeliefert
void* my_malloc(int byteCount)
{
if(!b_initialized)
initialize();
//Wenn der insgesamt verfuegbare Speicherplatz kleiner ist
//als der angeforderte, koennen wir gleich aufhoeren!
if(byteCount > get_free_space())
return(NULL);
//SUCHE NACH EINEM GEEIGNETEN FREIEN SPEICHERBLOCK, MIT MEHR ALS <byteCount>
//VIELEN BYTES
memoryBlock* block = head;
while(block != NULL)
{
if(block->dataLength > byteCount && block->state == not_allocated)
goto allocate_memory;
block = block->nextBlock;
}
// FALLS ES KEIN PASSENDES ELEMENT GIBT, GEBEN WIR NULL ZURÜCK.
return(NULL);
//Der Knoten block hat genuegend Speicherplatz
allocate_memory:
// UNTERTEILUNG DIESES BLOCKS, SO DASS NICHT UNNÖTIG VIEL SPEICHERPLATZ VERBRAUCHT WIRD
// UND RÜCKGABE DES ZEIGERS AUF DEN ZU BENUTZENDEN SPEICHERBEREICH
return splitBlock(block, byteCount)->data;
}
void * realloc(void * ptr, size_t size)
{
char * charPtr = static_cast<char *>(ptr);
Block & block = blocks.at(charPtr);
Block & next = nextBlock(charPtr);
/* There is enough place ahead of the current block */
if(block.size == size)
{
}
else if(block.size > size)
{
splitBlock(block, size);
Block & rest = blocks.at(block.ptr + size);
markBlockFree(rest);
if(next.free)
{
resizeBlock(rest, rest.size + next.size);
removeBlock(next);
}
}
else if(next.free && block.size + next.size >= size)
{
splitBlock(next, size-block.size);
removeBlock(next);
resizeBlock(block, size);
}
else
{
void * newPtr = alloc(size);
if(newPtr != NULL)
{
memcpy(newPtr, ptr, block.size);
free(ptr);
ptr = newPtr;
}
}
#ifdef SELFTEST
selfTest();
#endif
return ptr;
}
/* add a mafAli to the set */
static void addMafAli(struct malnSet *malnSet, struct mafAli *mafAli, int maxInputBlkWidth, double defaultBranchLength, struct Genome *treelessRootGenome) {
struct malnBlk *blk = mafAliToMAlnBlk(malnSet->genomes, mafAli, defaultBranchLength, treelessRootGenome);
if (blk->alnWidth < maxInputBlkWidth) {
malnSet_addBlk(malnSet, blk);
} else {
splitBlock(malnSet, maxInputBlkWidth, blk);
malnBlk_destruct(blk);
}
}
/**
* @brief Allocate a variable sized object on the memory pool.
* @param pool The pool to allocate from.
* @param size The size of the object to allocate.
* @return A valid address on success, NULL on failure.
*/
void *lpx_mempool_variable_alloc(lpx_mempool_variable_t *pool, long size)
{
void *candidateBlock = NULL;
int unlockNeeded = 0;
if (UNLIKELY(pool == NULL)) {
return NULL;
}
// Lock the mutex if needed.
if (pool->poolMutex != NULL) {
if (0 != pthread_mutex_lock(pool->poolMutex)) {
return NULL;
}
unlockNeeded = 1;
}
// First off, adjust the size to accomodate the metadata.
size += MEMPOOL_PER_BLOCK_OVERHEAD;
if (size < 3 * sizeof(long)) {
// Because this should be linkable back into the list.
size += 3 * sizeof(long);
}
// Find the first fit block from the free list.
candidateBlock = findFirstFit(pool, size);
if (candidateBlock == NULL) {
if (unlockNeeded) {
pthread_mutex_unlock(pool->poolMutex);
}
return NULL;
}
// Split the block and re-link the free list.
candidateBlock = splitBlock(pool, candidateBlock, &size);
if (candidateBlock == NULL) {
if (unlockNeeded) {
pthread_mutex_lock(pool->poolMutex);
}
return NULL;
}
// Prep the block for return.
((long *)candidateBlock)[0] = (long)pool;
((long *)candidateBlock)[1] = size;
// Unlock the mutex if needed.
if (pool->poolMutex != NULL) {
if (0 != pthread_mutex_unlock(pool->poolMutex)) {
return NULL;
}
}
// &candidateBlock[2] is the start of the user memory block.
return &(((long *)candidateBlock)[2]);
}
//versucht einen Speicherbereich mit <byteCount> vielen Bytes zu reservieren
//Falls dies nicht gelingt wird ein NULL (0) Pointer zurueckgeliefert
void* my_malloc(int byteCount)
{
if(!b_initialized)
{
initialize();
}
//DEBUG
//printf("mAllocating..%d\n",byteCount);
//Wenn der insgesamt verfuegbare Speicherplatz kleiner ist
//als der angeforderte, koennen wir gleich aufhoeren!
if(byteCount > get_free_space())
{
return(NULL);
}
memoryBlock *block = head;
//TODO - WIP - seems finished - needs testing - works
//SUCHE NACH EINEM GEEIGNETEN FREIEN SPEICHERBLOCK, MIT MEHR ALS <byteCount>
//VIELEN BYTES
// + memoryBlockHeaderSize ? nvm .. bei einer anforderung die die gesamte blockgroesse benoetigt muss kein header fuer einen splitBlock beruecksichtigt werden
memoryBlock *return_blockData = NULL;
while(block != NULL)
{
if(block->state == not_allocated){
if(block->dataLength >= byteCount){
if(return_blockData == NULL){
return_blockData = block;
}else{
if(return_blockData->dataLength > block->dataLength){
return_blockData = block;
}
}
}
}
block = block->nextBlock;
}
// FALLS ES KEIN PASSENDES ELEMENT GIBT, GEBEN WIR NULL ZURUECK.
if(return_blockData == NULL){
return NULL;
}
// Der Knoten block hat genuegend Speicherplatz
//if((return_blockData->dataLength) >= (byteCount+memoryBlockHeaderSize)){
//UNTERTEILUNG DIESES BLOCKS, SO DASS NICHT UNNOETIG VIEL SPEICHERPLATZ VERBRAUCHT WIRD#
splitBlock(return_blockData,byteCount);
//}else{
//ERROR
//printf("Nicht genug Platz fuer Speicher %d UND header %d in %d",byteCount,memoryBlockHeaderSize,return_blockData->dataLength);
//return NULL;
//}
// UND MARKIERE DIESEN BLOCK
return_blockData->state = allocated;
//DEBUG
//printf("mAllocated!\n");
//RueCKGABE DES ZEIGERS AUF DEN ZU BENUTZENDEN SPEICHERBEREICH
return return_blockData->data;
}
/**********************************************************
* mm_malloc
* Allocate a block of size bytes.
* The type of search is determined by find_fit
* The decision of splitting is determined by spiltBlock
* If no block satisfies the request, the heap is extended
**********************************************************/
void *mm_malloc(size_t size) {
size_t asize; /* adjusted block size */
size_t extendsize; /* amount to extend heap if no fit */
char * bp;
/* Ignore spurious requests */
if (size == 0)
return NULL;
/* Adjust block size to include overhead and alignment reqs. */
if (size <= DSIZE)
asize = 2 * DSIZE;
else
asize = DSIZE * ((size + (DSIZE) + (DSIZE - 1)) / DSIZE);
/* Search the free list for a fit */
if ((bp = find_fit(asize)) != NULL) {
//remove from the free list
removeFromFreeList(bp);
//break the block into smaller one if possible
bp = splitBlock(bp, asize);
size_t bsize = GET_SIZE(HDRP(bp));
//place the block
setBlockHeaderFooter(bp, bsize, 1);
return bp;
}
/* No fit found. Get more memory and place the block */
//Increasing chunksize by 16B gives huge improvment in binary test case.
//we incease 16 for the reason that it matches size of header and footer
extendsize = MAX(asize, CHUNKSIZE + 16);
if ((bp = extend_heap(extendsize / WSIZE)) == NULL)
return NULL;
splitBlock(bp, asize);
place(bp, asize);
return bp;
}
void* sf_malloc(size_t size){
if(size < 0x1 || size > 0x100000000) return NULL; /* invalid request size */
if(start == end) init_heapSpace(); /* no call has been made to request heap space, do so here */
uintptr_t *cursor = (uintptr_t *) NULL_POINTER;
restart_search: /* kind of like the cache if there's no space big enough(miss), get that space and tell you to ask me again */
cursor = (uintptr_t*) head;
uintptr_t allocate_size = 0;
if(size < 16)
allocate_size = 16;
else if (size % 8 == 0)
allocate_size = (uintptr_t) size;
else
allocate_size =(uintptr_t) (size + (8 - (size % 8)));
if((allocate_size / 8) % 2 != 0) allocate_size += 8;
uintptr_t *result = (uintptr_t*) NULL_POINTER;
if(cursor != (uintptr_t *)NULL_POINTER){
while(get_loadSize(cursor) < allocate_size && (uintptr_t) *(cursor + 1) != NULL_POINTER)
cursor = (uintptr_t *) *(cursor + 1); /* cursor = cursor.getNext(); */
uintptr_t loadSize = get_loadSize(cursor);
/* if the request fits and there is space to split */
if(loadSize > (allocate_size + 48)){
uintptr_t **ptr = &cursor;
splitBlock(ptr, size, allocate_size, loadSize);
result = cursor + 1;
}
else if(loadSize >= allocate_size){
uintptr_t **ptr = &cursor;
allocateBlock(ptr, size, allocate_size);
result = cursor + 1;
}else if(loadSize < allocate_size){
addHeapSpace(allocate_size);
goto restart_search;
}
}
/* could not find a space big enough to hold the requested size */
else {
addHeapSpace(allocate_size);
goto restart_search;
}
return result;
}
void * alloc(size_t size)
{
char * ptr = findPtrForSize(size);
if(ptr != NULL)
{
splitBlock(blocks.at(ptr), size);
markBlockBusy(blocks.at(ptr));
}
#ifdef SELFTEST
selfTest();
#endif
return static_cast<void *>(ptr);
}
struct nca* Free(struct nca *prev, size_t size){
struct nca *thisnca = zee;
while (true){
if (!thisnca){
return nca2(prev ,size);
}
if (thisnca&&thisnca->free && (thisnca->size)>=size){
thisnca=splitBlock(thisnca,size);
thisnca->free=false;
return thisnca;
}
prev = thisnca;
thisnca = thisnca->next;
}
return 0;
}
static void buildNewStatusString( int block, int id )
{
char *mod;
mod = findBlockString( block );
switch( id ) {
case SS_SPLIT:
splitBlock( block, mod );
break;
case SS_DESTROY:
destroyBlock( block, mod );
break;
case SS_DEFAULTS:
buildDefaults();
break;
default:
buildNewItem( mod, id );
}
}
//versucht einen Speicherbereich mit <byteCount> vielen Bytes zu reservieren
//Falls dies nicht gelingt wird ein NULL (0) Pointer zurueckgeliefert
void* my_malloc(int byteCount)
{
if(!b_initialized)
{
initialize();
}
//Wenn der insgesamt verfuegbare Speicherplatz kleiner ist
//als der angeforderte, koennen wir gleich aufhoeren!
if(byteCount > get_free_space())
{
return(NULL);
}
//TODO - DONE
//SUCHE NACH EINEM GEEIGNETEN FREIEN SPEICHERBLOCK, MIT MEHR ALS <byteCount>
//VIELEN BYTES
memoryBlock* block = head;
while ( 1 ){
// Keine geeigneter Block gefunden
if ( block == NULL ){
// jetzt m�sste man anfangen zu defragmentieren
// geht nur leider ohne virtuelle Speicheradressen nicht,
// da sonst die von uns zur�ckgegebenen Pointer ung�ltig werden
return NULL;
}
// Einen Block gefunden, der gro� genug ist
if ( block->state == not_allocated && block->dataLength >= byteCount ){
break;
}
block = block->nextBlock;
}
//UNTERTEILUNG DIESES BLOCKS, SO DASS NICHT UNN�TIG VIEL SPEICHERPLATZ VERBRAUCHT WIRD
block = splitBlock ( block, byteCount );
//R�CKGABE DES ZEIGERS AUF DEN ZU BENUTZENDEN SPEICHERBEREICH
block->state = allocated;
return (void *) block->data;
}
static void splitBlock(int splitIdx, int neededIdx, metadata_t *currBlock) {
// base condition
if (splitIdx == neededIdx) {
return;
} else {
// if there is a buddy, split the first one
if (currBlock->next != NULL) {
metadata_t *temp = currBlock->next;
// remove the splited block
currBlock->prev = NULL;
currBlock->next = NULL;
currBlock->size /= 2;
currBlock->in_use = 0;
// next block becomes the head
temp->prev = NULL;
freelist[splitIdx] = temp;
} else {
// if there is not a buddy, split it directly
currBlock->prev = NULL;
currBlock->size /= 2;
currBlock->in_use = 0;
freelist[splitIdx] = NULL;
}
// the addresses of two new blocks
splitIdx--;
freelist[splitIdx] = currBlock;
metadata_t *newBlock = (metadata_t *) ((char *) currBlock + currBlock->size);
newBlock->size = currBlock->size;
newBlock->in_use = 0;
newBlock->next = NULL;
newBlock->prev = currBlock;
currBlock->next = newBlock;
// recursion occurs here!
splitBlock(splitIdx, neededIdx, currBlock);
}
}
// Versucht einen Speicherbereich mit <byteCount> vielen Bytes zu reservieren
// Falls dies nicht gelingt wird ein NULL (0) Pointer zurueckgeliefert
void* my_malloc(int byteCount)
{
if(!b_initialized)
{
initialize();
}
// Wenn der insgesamt verfuegbare Speicherplatz kleiner ist
// als der angeforderte, koennen wir gleich aufhoeren!
if(byteCount > get_free_space())
{
return(NULL);
}
memoryBlock *block = head;
// TODO
// SUCHE NACH EINEM GEEIGNETEN FREIEN SPEICHERBLOCK, MIT MEHR ALS <byteCount>
// VIELEN BYTES
//
do
{
if(block->state == not_allocated && block->dataSize >= byteCount + memoryBlockHeaderSize) break;
block = block->nextMemBlock;
}
while(block != 0);
// FALLS ES KEIN PASSENDES ELEMENT GIBT, GEBEN WIR NULL ZURUECK.
if(block == 0) return 0;
// Der Knoten block hat genuegend Speicherplatz
// UNTERTEILUNG DIESES BLOCKS, SO DASS NICHT UNNOETIG VIEL SPEICHERPLATZ VERBRAUCHT WIRD
// UND MARKIERE DIESEN BLOCK
block = splitBlock(block,byteCount);
block->state = allocated;
// RUECKGABE DES ZEIGERS AUF DEN ZU BENUTZENDEN SPEICHERBEREICH
return block->data;
}
/**********************************************************
* mm_realloc
* Deals with a few cases:
* 1. if the realloc size is smaller than current size
* we split the current block and then put the extra part
* to free list
* 2. if the next block of the current block is freed, we check if
* merge these two blocks can lead to a fit block for realloc
* 3. if the current block is at the end of heap,
* we just increase the heap by the required amount and then merge
* that amount into that block
* 4. if the new size is same as old size we do nothing
* 5. if the new size is 0, same as free
* 6. else we malloc a new block and then copy the data from old block
*********************************************************/
void *mm_realloc(void *ptr, size_t size) {
/* If size == 0 then this is just free, and we return NULL. */
//case 5
if (size == 0) {
mm_free(ptr);
return NULL;
}
/* If oldptr is NULL, then this is just malloc. */
if (ptr == NULL)
return (mm_malloc(size));
void *oldptr = ptr;
void *newptr;
size_t copySize;
size_t oldSize = GET_SIZE(HDRP(oldptr));
size_t asize;
/* Adjust block size to include overhead and alignment reqs. */
if (size <= DSIZE)
asize = 2 * DSIZE;
else
asize = DSIZE * ((size + (DSIZE) + (DSIZE - 1)) / DSIZE);
//case 4 (see above)
if (oldSize == asize) {
return ptr;
} //case 1
else if (oldSize > asize) {
void* newptr = splitBlock(ptr, asize);
place(newptr, asize);
return newptr;
} //case 2
else if (GET_SIZE(HDRP(NEXT_BLKP(ptr))) != 0) {
if (GET_ALLOC(HDRP(NEXT_BLKP(ptr))) == 0) {
//get the merge size after merge with next block
size_t msize = oldSize + GET_SIZE(HDRP(NEXT_BLKP(ptr)));
if (msize >= asize) {
//coalesce next block with current block
removeFromFreeList(NEXT_BLKP(ptr));
PUT(HDRP(ptr), PACK(msize, 0));
PUT(FTRP(ptr), PACK(msize, 0));
//split block if there is extra space
void* newptr = splitBlock(ptr, asize);
place(newptr, asize);
return newptr;
}
}
} //case 3
else if (GET_SIZE(HDRP(NEXT_BLKP(ptr))) == 0) {
//new size larger than old size and next block is epilogue
//we can extend the heap and then coalesce
size_t esize = asize - oldSize; //calculate sufficient space to extend
//extend heap by the sufficient amount
void* ebp = extend_heap(esize / WSIZE);
if (ebp != NULL) {
//coalesce the extend space into current block
PUT(HDRP(ptr), PACK(asize, 1));
PUT(FTRP(ptr), PACK(asize, 1));
return ptr;
}
}
//case 6
newptr = mm_malloc(size);
if (newptr == NULL)
return NULL;
/* Copy the old data. */
copySize = GET_SIZE(HDRP(oldptr));
memcpy(newptr, oldptr, copySize);
mm_free(oldptr);
return newptr;
}
void* my_malloc(size_t size)
{
// calculate the needed size
int total_size = size + sizeof(metadata_t);
// if the requested size is beyond our largest block size
if (total_size > SBRK_SIZE) {
ERRNO = SINGLE_REQUEST_TOO_LARGE;
return NULL;
}
// set up the heap if it is uninitialized
if (!heap) {
setupHeap();
if (ERRNO == OUT_OF_MEMORY) {
return NULL;
}
}
// get index of the free list to allocate memory to the user
int idx = getIdx(total_size);
metadata_t *allocBlock = NULL;
// if we have a memory block to allocate
if (freelist[idx] != NULL) {
// just simply return the first block
allocBlock = freelist[idx];
// if there is the next block
if (allocBlock->next != NULL) {
allocBlock->next->prev = NULL;
freelist[idx] = allocBlock->next;
} else {
freelist[idx] = NULL;
}
// remove this block/
allocBlock->in_use = 1;
allocBlock->prev = NULL;
allocBlock->next = NULL;
// return the block
return ((char*)allocBlock + sizeof(metadata_t));
}
// if we do not have a memory block to allocate
// we split the second smallest blocks into blocks of needed size
int splitIdx = idx + 1;
while (freelist[splitIdx] == NULL) {
splitIdx++;
}
// if there are no blocks to split
if (splitIdx == 8) {
// set up a new heap
setupHeap();
if (ERRNO == OUT_OF_MEMORY) {
return NULL;
}
} else { // if a block can be split
splitBlock(splitIdx, idx, freelist[splitIdx]); // a recursive function
}
// call my_malloc() again to allocate memory
allocBlock = my_malloc(size);
// set the error code
ERRNO = NO_ERROR;
return allocBlock;
}