| 1 |
/** |
| 2 |
* balloc.C: Block allocation of memory segments |
| 3 |
* Rights to this code are documented in doc/pod/license.pod. |
| 4 |
* |
| 5 |
* Copyright © 2005-2007 Atheme Project (http://www.atheme.org) |
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*/ |
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|
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static char const rcsid[] = "$Id: balloc.C,v 1.3 2007-07-21 13:23:21 pippijn Exp $"; |
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|
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#include "atheme.h" |
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|
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#ifdef HAVE_MMAP /* We've got mmap() that is good */ |
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# include <sys/mman.h> |
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# ifdef MAP_ANONYMOUS |
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# ifndef MAP_ANON |
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# define MAP_ANON MAP_ANONYMOUS |
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# endif |
| 18 |
# endif |
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#else |
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# define MAP_PRIVATE 0 |
| 21 |
# define MAP_ANON 0 |
| 22 |
# define MAP_FAILED 0 |
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# define PROT_READ 0 |
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# define PROT_WRITE 0 |
| 25 |
#endif |
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|
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static int newblock (BlockHeap *bh); |
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static int BlockHeapGarbageCollect (BlockHeap *); |
| 29 |
static void block_heap_gc (void *unused); |
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static list_t heap_lists; |
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|
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#define blockheap_fail(x) _blockheap_fail(x, __FILE__, __LINE__) |
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|
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static void |
| 35 |
_blockheap_fail (const char *reason, const char *file, int line) |
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{ |
| 37 |
slog (LG_INFO, "Blockheap failure: %s (%s:%d)", reason, file, line); |
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runflags |= RF_SHUTDOWN; |
| 39 |
} |
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|
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#ifndef HAVE_MMAP |
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/* |
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* static void mmap(void *hint, size_t len, unsigned int prot, |
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* unsigned int flags, unsigned int fd, unsigned int off) |
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* |
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* Inputs - mmap style arguments. |
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* Output - None |
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* Side Effects - Memory is allocated to the block allocator. |
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*/ |
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static void * |
| 51 |
mmap (void *hint, size_t len, unsigned int prot, unsigned int flags, unsigned int fd, unsigned int off) |
| 52 |
{ |
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void *ptr = smalloc (len); |
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|
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if (!ptr) |
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blockheap_fail ("smalloc() failed."); |
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|
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memset (ptr, 0, len); |
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|
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return ptr; |
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} |
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|
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/* |
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* static void munmap(void *addr, size_t len) |
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* |
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* Inputs - munmap style arguments. |
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* Output - None |
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* Side Effects - Memory is returned back to the OS. |
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*/ |
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static void |
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munmap (void *addr, size_t len) |
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{ |
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if (!addr) |
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blockheap_fail ("no address to unmap."); |
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|
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free (addr); |
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} |
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#endif |
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|
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/* |
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* static void free_block(void *ptr, size_t size) |
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* |
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* Inputs: The block and its size |
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* Output: None |
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* Side Effects: Returns memory for the block back to the OS |
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*/ |
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static void |
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free_block (void *ptr, size_t size) |
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{ |
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munmap (ptr, size); |
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} |
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|
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|
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/* |
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* void initBlockHeap(void) |
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* |
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* Inputs: None |
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* Outputs: None |
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* Side Effects: Initializes the block heap |
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*/ |
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|
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void |
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initBlockHeap (void) |
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{ |
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#ifndef NOBALLOC |
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event_add ("block_heap_gc", block_heap_gc, NULL, 60); |
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#endif |
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} |
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|
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#ifndef NOBALLOC |
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/* |
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* static void *get_block(size_t size) |
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* |
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* Input: Size of block to allocate |
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* Output: Pointer to new block |
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* Side Effects: None |
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*/ |
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static void * |
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get_block (size_t size) |
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{ |
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void *ptr; |
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ptr = mmap (NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0); |
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|
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if (ptr == MAP_FAILED) |
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ptr = NULL; |
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|
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return (ptr); |
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} |
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|
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|
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static void |
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block_heap_gc (void *unused) |
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{ |
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node_t *ptr, *tptr; |
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|
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LIST_FOREACH_SAFE (ptr, tptr, heap_lists.head) |
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{ |
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BlockHeapGarbageCollect (static_cast<BlockHeap *> (ptr->data)); |
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} |
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} |
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|
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/* ************************************************************************ */ |
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/* FUNCTION DOCUMENTATION: */ |
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/* newblock */ |
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/* Description: */ |
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/* Allocates a new block for addition to a blockheap */ |
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/* Parameters: */ |
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/* bh (IN): Pointer to parent blockheap. */ |
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/* Returns: */ |
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/* 0 if successful, 1 if not */ |
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/* ************************************************************************ */ |
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|
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static int |
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newblock (BlockHeap *bh) |
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{ |
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MemBlock *newblk; |
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Block *b; |
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unsigned long i; |
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void *offset; |
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|
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/* Setup the initial data structure. */ |
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b = (Block *) scalloc (1, sizeof (Block)); |
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|
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if (b == NULL) |
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return (1); |
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|
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b->free_list.head = b->free_list.tail = NULL; |
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b->used_list.head = b->used_list.tail = NULL; |
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b->next = bh->base; |
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|
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b->alloc_size = (bh->elemsPerBlock + 1) * (bh->elemSize + sizeof (MemBlock)); |
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|
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b->elems = get_block (b->alloc_size); |
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|
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if (b->elems == NULL) |
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return (1); |
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|
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offset = b->elems; |
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|
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/* Setup our blocks now */ |
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for (i = 0; i < bh->elemsPerBlock; i++) |
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{ |
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void *data; |
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newblk = static_cast<MemBlock *> (offset); |
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newblk->block = b; |
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#ifdef DEBUG_BALLOC |
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newblk->magic = BALLOC_MAGIC; |
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#endif |
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data = (void *) ((size_t) offset + sizeof (MemBlock)); |
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newblk->block = b; |
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node_add (data, &newblk->self, &b->free_list); |
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offset = (unsigned char *) ((unsigned char *) offset + bh->elemSize + sizeof (MemBlock)); |
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} |
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|
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++bh->blocksAllocated; |
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bh->freeElems += bh->elemsPerBlock; |
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bh->base = b; |
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|
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return (0); |
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} |
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#endif |
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|
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/* ************************************************************************ */ |
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/* FUNCTION DOCUMENTATION: */ |
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/* BlockHeapCreate */ |
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/* Description: */ |
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/* Creates a new blockheap from which smaller blocks can be allocated. */ |
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/* Intended to be used instead of multiple calls to malloc() when */ |
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/* performance is an issue. */ |
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/* Parameters: */ |
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/* elemsize (IN): Size of the basic element to be stored */ |
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/* elemsperblock (IN): Number of elements to be stored in a single block */ |
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/* of memory. When the blockheap runs out of free memory, it will */ |
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/* allocate elemsize * elemsperblock more. */ |
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/* Returns: */ |
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/* Pointer to new BlockHeap, or NULL if unsuccessful */ |
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/* ************************************************************************ */ |
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BlockHeap * |
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BlockHeapCreate (size_t elemsize, int elemsperblock) |
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{ |
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BlockHeap *bh; |
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|
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/* Catch idiotic requests up front */ |
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if ((elemsize <= 0) || (elemsperblock <= 0)) |
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{ |
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blockheap_fail ("Attempting to BlockHeapCreate idiotic sizes"); |
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} |
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|
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/* Allocate our new BlockHeap */ |
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bh = (BlockHeap *) scalloc (1, sizeof (BlockHeap)); |
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|
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if (bh == NULL) |
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{ |
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slog (LG_INFO, "Attempt to calloc() failed: (%s:%d)", __FILE__, __LINE__); |
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runflags |= RF_SHUTDOWN; |
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} |
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|
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#ifndef NOBALLOC |
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if ((elemsize % sizeof (void *)) != 0) |
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{ |
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/* Pad to even pointer boundary */ |
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elemsize += sizeof (void *); |
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elemsize &= ~(sizeof (void *) - 1); |
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} |
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#endif |
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|
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bh->elemSize = elemsize; |
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bh->elemsPerBlock = elemsperblock; |
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bh->blocksAllocated = 0; |
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bh->freeElems = 0; |
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bh->base = NULL; |
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|
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#ifndef NOBALLOC |
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/* Be sure our malloc was successful */ |
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if (newblock (bh)) |
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{ |
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if (bh != NULL) |
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free (bh); |
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slog (LG_INFO, "newblock() failed"); |
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runflags |= RF_SHUTDOWN; |
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} |
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#endif |
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|
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if (bh == NULL) |
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{ |
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blockheap_fail ("bh == NULL when it shouldn't be"); |
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} |
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node_add (bh, &bh->hlist, &heap_lists); |
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return (bh); |
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} |
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|
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/* ************************************************************************ */ |
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/* FUNCTION DOCUMENTATION: */ |
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/* BlockHeapAlloc */ |
| 275 |
/* Description: */ |
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/* Returns a pointer to a struct within our BlockHeap that's free for */ |
| 277 |
/* the taking. */ |
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/* Parameters: */ |
| 279 |
/* bh (IN): Pointer to the Blockheap. */ |
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/* Returns: */ |
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/* Pointer to a structure (void *), or NULL if unsuccessful. */ |
| 282 |
/* ************************************************************************ */ |
| 283 |
|
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void * |
| 285 |
BlockHeapAlloc (BlockHeap *bh) |
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{ |
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Block *walker; |
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node_t *new_node; |
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|
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if (bh == NULL) |
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{ |
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blockheap_fail ("Cannot allocate if bh == NULL"); |
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} |
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|
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#ifdef NOBALLOC |
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return smalloc (bh->elemSize); |
| 297 |
#else |
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if (bh->freeElems == 0) |
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{ |
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/* Allocate new block and assign */ |
| 301 |
/* newblock returns 1 if unsuccessful, 0 if not */ |
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|
| 303 |
if (newblock (bh)) |
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{ |
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/* That didn't work..try to garbage collect */ |
| 306 |
BlockHeapGarbageCollect (bh); |
| 307 |
if (bh->freeElems == 0) |
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{ |
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slog (LG_INFO, "newblock() failed and garbage collection didn't help"); |
| 310 |
runflags |= RF_SHUTDOWN; |
| 311 |
} |
| 312 |
} |
| 313 |
} |
| 314 |
|
| 315 |
for (walker = bh->base; walker != NULL; walker = walker->next) |
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{ |
| 317 |
if (LIST_LENGTH (&walker->free_list) > 0) |
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{ |
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bh->freeElems--; |
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new_node = walker->free_list.head; |
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node_move (new_node, &walker->free_list, &walker->used_list); |
| 322 |
if (new_node->data == NULL) |
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blockheap_fail ("new_node->data is NULL and that shouldn't happen!!!"); |
| 324 |
memset (new_node->data, 0, bh->elemSize); |
| 325 |
return (new_node->data); |
| 326 |
} |
| 327 |
} |
| 328 |
blockheap_fail ("BlockHeapAlloc failed, giving up"); |
| 329 |
return NULL; |
| 330 |
#endif |
| 331 |
} |
| 332 |
|
| 333 |
|
| 334 |
/* ************************************************************************ */ |
| 335 |
/* FUNCTION DOCUMENTATION: */ |
| 336 |
/* BlockHeapFree */ |
| 337 |
/* Description: */ |
| 338 |
/* Returns an element to the free pool, does not free() */ |
| 339 |
/* Parameters: */ |
| 340 |
/* bh (IN): Pointer to BlockHeap containing element */ |
| 341 |
/* ptr (in): Pointer to element to be "freed" */ |
| 342 |
/* Returns: */ |
| 343 |
/* 0 if successful, 1 if element not contained within BlockHeap. */ |
| 344 |
/* ************************************************************************ */ |
| 345 |
int |
| 346 |
BlockHeapFree (BlockHeap *bh, void *ptr) |
| 347 |
{ |
| 348 |
Block *block; |
| 349 |
struct MemBlock *memblock; |
| 350 |
|
| 351 |
if (bh == NULL) |
| 352 |
{ |
| 353 |
|
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slog (LG_DEBUG, "balloc.c:BlockHeapFree() bh == NULL"); |
| 355 |
return (1); |
| 356 |
} |
| 357 |
|
| 358 |
if (ptr == NULL) |
| 359 |
{ |
| 360 |
slog (LG_DEBUG, "balloc.c:BlockHeapFree() ptr == NULL"); |
| 361 |
return (1); |
| 362 |
} |
| 363 |
|
| 364 |
#ifdef NOBALLOC |
| 365 |
free (ptr); |
| 366 |
#else |
| 367 |
memblock = static_cast<MemBlock *> ((void *) ((size_t) ptr - sizeof (MemBlock))); |
| 368 |
#ifdef DEBUG_BALLOC |
| 369 |
if (memblock->magic != BALLOC_MAGIC) |
| 370 |
{ |
| 371 |
blockheap_fail ("memblock->magic != BALLOC_MAGIC"); |
| 372 |
runflags |= RF_SHUTDOWN; |
| 373 |
} |
| 374 |
#endif |
| 375 |
if (memblock->block == NULL) |
| 376 |
{ |
| 377 |
blockheap_fail ("memblock->block == NULL, not a valid block?"); |
| 378 |
runflags |= RF_SHUTDOWN; |
| 379 |
} |
| 380 |
|
| 381 |
block = memblock->block; |
| 382 |
bh->freeElems++; |
| 383 |
node_move (&memblock->self, &block->used_list, &block->free_list); |
| 384 |
#endif |
| 385 |
return (0); |
| 386 |
} |
| 387 |
|
| 388 |
/* ************************************************************************ */ |
| 389 |
/* FUNCTION DOCUMENTATION: */ |
| 390 |
/* BlockHeapGarbageCollect */ |
| 391 |
/* Description: */ |
| 392 |
/* Performs garbage collection on the block heap. Any blocks that are */ |
| 393 |
/* completely unallocated are removed from the heap. Garbage collection */ |
| 394 |
/* will never remove the root node of the heap. */ |
| 395 |
/* Parameters: */ |
| 396 |
/* bh (IN): Pointer to the BlockHeap to be cleaned up */ |
| 397 |
/* Returns: */ |
| 398 |
/* 0 if successful, 1 if bh == NULL */ |
| 399 |
/* ************************************************************************ */ |
| 400 |
static int |
| 401 |
BlockHeapGarbageCollect (BlockHeap *bh) |
| 402 |
{ |
| 403 |
#ifndef NOBALLOC |
| 404 |
Block *walker, *last; |
| 405 |
if (bh == NULL) |
| 406 |
{ |
| 407 |
return (1); |
| 408 |
} |
| 409 |
|
| 410 |
if (bh->freeElems < bh->elemsPerBlock || bh->blocksAllocated == 1) |
| 411 |
{ |
| 412 |
/* There couldn't possibly be an entire free block. Return. */ |
| 413 |
return (0); |
| 414 |
} |
| 415 |
|
| 416 |
last = NULL; |
| 417 |
walker = bh->base; |
| 418 |
|
| 419 |
while (walker != NULL) |
| 420 |
{ |
| 421 |
if ((LIST_LENGTH (&walker->free_list) == bh->elemsPerBlock) != 0) |
| 422 |
{ |
| 423 |
free_block (walker->elems, walker->alloc_size); |
| 424 |
if (last != NULL) |
| 425 |
{ |
| 426 |
last->next = walker->next; |
| 427 |
if (walker != NULL) |
| 428 |
free (walker); |
| 429 |
walker = last->next; |
| 430 |
} |
| 431 |
else |
| 432 |
{ |
| 433 |
bh->base = walker->next; |
| 434 |
if (walker != NULL) |
| 435 |
free (walker); |
| 436 |
walker = bh->base; |
| 437 |
} |
| 438 |
bh->blocksAllocated--; |
| 439 |
bh->freeElems -= bh->elemsPerBlock; |
| 440 |
} |
| 441 |
else |
| 442 |
{ |
| 443 |
last = walker; |
| 444 |
walker = walker->next; |
| 445 |
} |
| 446 |
} |
| 447 |
return (0); |
| 448 |
#endif |
| 449 |
} |
| 450 |
|
| 451 |
/* ************************************************************************ */ |
| 452 |
/* FUNCTION DOCUMENTATION: */ |
| 453 |
/* BlockHeapDestroy */ |
| 454 |
/* Description: */ |
| 455 |
/* Completely free()s a BlockHeap. Use for cleanup. */ |
| 456 |
/* Parameters: */ |
| 457 |
/* bh (IN): Pointer to the BlockHeap to be destroyed. */ |
| 458 |
/* Returns: */ |
| 459 |
/* 0 if successful, 1 if bh == NULL */ |
| 460 |
/* ************************************************************************ */ |
| 461 |
int |
| 462 |
BlockHeapDestroy (BlockHeap *bh) |
| 463 |
{ |
| 464 |
Block *walker, *next; |
| 465 |
|
| 466 |
if (bh == NULL) |
| 467 |
{ |
| 468 |
return (1); |
| 469 |
} |
| 470 |
|
| 471 |
#ifndef NOBALLOC |
| 472 |
for (walker = bh->base; walker != NULL; walker = next) |
| 473 |
{ |
| 474 |
next = walker->next; |
| 475 |
free_block (walker->elems, walker->alloc_size); |
| 476 |
if (walker != NULL) |
| 477 |
free (walker); |
| 478 |
} |
| 479 |
#endif |
| 480 |
node_del (&bh->hlist, &heap_lists); |
| 481 |
free (bh); |
| 482 |
return (0); |
| 483 |
} |
| 484 |
|
| 485 |
void |
| 486 |
BlockHeapUsage (BlockHeap *bh, size_t * bused, size_t * bfree, size_t * bmemusage) |
| 487 |
{ |
| 488 |
size_t used; |
| 489 |
size_t freem; |
| 490 |
size_t memusage; |
| 491 |
if (bh == NULL) |
| 492 |
{ |
| 493 |
return; |
| 494 |
} |
| 495 |
|
| 496 |
#ifdef NOBALLOC |
| 497 |
freem = used = memusage = 0; |
| 498 |
#else |
| 499 |
freem = bh->freeElems; |
| 500 |
used = (bh->blocksAllocated * bh->elemsPerBlock) - bh->freeElems; |
| 501 |
memusage = used * (bh->elemSize + sizeof (MemBlock)); |
| 502 |
#endif |
| 503 |
|
| 504 |
if (bused != NULL) |
| 505 |
*bused = used; |
| 506 |
if (bfree != NULL) |
| 507 |
*bfree = freem; |
| 508 |
if (bmemusage != NULL) |
| 509 |
*bmemusage = memusage; |
| 510 |
} |
