+++ /dev/null
-/* Free a block of memory allocated by `mmalloc'. */
-
-/* Copyright (c) 2010-2020. The SimGrid Team. All rights reserved. */
-
-/* This program is free software; you can redistribute it and/or modify it
- * under the terms of the license (GNU LGPL) which comes with this package. */
-
-/* Copyright 1990, 1991, 1992 Free Software Foundation
-
- Written May 1989 by Mike Haertel.
- Heavily modified Mar 1992 by Fred Fish. (fnf@cygnus.com) */
-
-#include "mmprivate.h"
-#include "xbt/ex.h"
-#include "mc/mc.h"
-
-/* Return memory to the heap.
- Like `mfree' but don't call a mfree_hook if there is one. */
-
-/* Return memory to the heap. */
-void mfree(struct mdesc *mdp, void *ptr)
-{
- size_t frag_nb;
- size_t i;
- int it;
-
- if (ptr == NULL)
- return;
-
- size_t block = BLOCK(ptr);
-
- if ((char *) ptr < (char *) mdp->heapbase || block > mdp->heapsize) {
- fprintf(stderr,"Ouch, this pointer is not mine, I refuse to free it. Give me valid pointers, or give me death!!\n");
- abort();
- }
-
- int type = mdp->heapinfo[block].type;
-
- switch (type) {
- case MMALLOC_TYPE_HEAPINFO:
- UNLOCK(mdp);
- THROWF(0, "Asked to free a fragment in a heapinfo block. I'm confused.\n");
- break;
-
- case MMALLOC_TYPE_FREE: /* Already free */
- UNLOCK(mdp);
- THROWF(0, "Asked to free a fragment in a block that is already free. I'm puzzled.\n");
- break;
-
- case MMALLOC_TYPE_UNFRAGMENTED:
- /* Get as many statistics as early as we can. */
- mdp -> heapstats.chunks_used--;
- mdp -> heapstats.bytes_used -=
- mdp -> heapinfo[block].busy_block.size * BLOCKSIZE;
- mdp -> heapstats.bytes_free +=
- mdp -> heapinfo[block].busy_block.size * BLOCKSIZE;
-
- if (MC_is_active() && mdp->heapinfo[block].busy_block.ignore > 0)
- MC_unignore_heap(ptr, mdp->heapinfo[block].busy_block.busy_size);
-
- /* Find the free cluster previous to this one in the free list.
- Start searching at the last block referenced; this may benefit
- programs with locality of allocation. */
- i = mdp->heapindex;
- if (i > block) {
- while (i > block) {
- i = mdp->heapinfo[i].free_block.prev;
- }
- } else {
- do {
- i = mdp->heapinfo[i].free_block.next;
- }
- while ((i != 0) && (i < block));
- i = mdp->heapinfo[i].free_block.prev;
- }
-
- /* Determine how to link this block into the free list. */
- if (block == i + mdp->heapinfo[i].free_block.size) {
-
- /* Coalesce this block with its predecessor. */
- mdp->heapinfo[i].free_block.size += mdp->heapinfo[block].busy_block.size;
- /* Mark all my ex-blocks as free */
- for (it=0; it<mdp->heapinfo[block].busy_block.size; it++) {
- if (mdp->heapinfo[block+it].type < 0) {
- fprintf(stderr,"Internal Error: Asked to free a block already marked as free (block=%lu it=%d type=%lu). Please report this bug.\n",
- (unsigned long)block,it,(unsigned long)mdp->heapinfo[block].type);
- abort();
- }
- mdp->heapinfo[block+it].type = MMALLOC_TYPE_FREE;
- }
-
- block = i;
- } else {
- /* Really link this block back into the free list. */
- mdp->heapinfo[block].free_block.size = mdp->heapinfo[block].busy_block.size;
- mdp->heapinfo[block].free_block.next = mdp->heapinfo[i].free_block.next;
- mdp->heapinfo[block].free_block.prev = i;
- mdp->heapinfo[i].free_block.next = block;
- mdp->heapinfo[mdp->heapinfo[block].free_block.next].free_block.prev = block;
- mdp -> heapstats.chunks_free++;
- /* Mark all my ex-blocks as free */
- for (it=0; it<mdp->heapinfo[block].free_block.size; it++) {
- if (mdp->heapinfo[block+it].type <0) {
- fprintf(stderr,"Internal error: Asked to free a block already marked as free (block=%lu it=%d/%lu type=%lu). Please report this bug.\n",
- (unsigned long)block,it,(unsigned long)mdp->heapinfo[block].free_block.size,(unsigned long)mdp->heapinfo[block].type);
- abort();
- }
- mdp->heapinfo[block+it].type = MMALLOC_TYPE_FREE;
- }
- }
-
- /* Now that the block is linked in, see if we can coalesce it
- with its successor (by deleting its successor from the list
- and adding in its size). */
- if (block + mdp->heapinfo[block].free_block.size ==
- mdp->heapinfo[block].free_block.next) {
- mdp->heapinfo[block].free_block.size
- += mdp->heapinfo[mdp->heapinfo[block].free_block.next].free_block.size;
- mdp->heapinfo[block].free_block.next
- = mdp->heapinfo[mdp->heapinfo[block].free_block.next].free_block.next;
- mdp->heapinfo[mdp->heapinfo[block].free_block.next].free_block.prev = block;
- mdp -> heapstats.chunks_free--;
- }
-
- /* Now see if we can return stuff to the system. */
-#if 0
- blocks = mdp -> heapinfo[block].free.size;
- if (blocks >= FINAL_FREE_BLOCKS && block + blocks == mdp -> heaplimit
- && mdp -> morecore (mdp, 0) == ADDRESS (block + blocks))
- {
- register size_t bytes = blocks * BLOCKSIZE;
- mdp -> heaplimit -= blocks;
- mdp -> morecore (mdp, -bytes);
- mdp -> heapinfo[mdp -> heapinfo[block].free.prev].free.next
- = mdp -> heapinfo[block].free.next;
- mdp -> heapinfo[mdp -> heapinfo[block].free.next].free.prev
- = mdp -> heapinfo[block].free.prev;
- block = mdp -> heapinfo[block].free.prev;
- mdp -> heapstats.chunks_free--;
- mdp -> heapstats.bytes_free -= bytes;
- }
-#endif
-
- /* Set the next search to begin at this block.
- This is probably important to the trick where realloc returns the block to
- the system before reasking for the same block with a bigger size. */
- mdp->heapindex = block;
- break;
-
- default:
- if (type < 0) {
- fprintf(stderr, "Unknown mmalloc block type.\n");
- abort();
- }
-
- /* Do some of the statistics. */
- mdp -> heapstats.chunks_used--;
- mdp -> heapstats.bytes_used -= 1 << type;
- mdp -> heapstats.chunks_free++;
- mdp -> heapstats.bytes_free += 1 << type;
-
- frag_nb = RESIDUAL(ptr, BLOCKSIZE) >> type;
-
- if( mdp->heapinfo[block].busy_frag.frag_size[frag_nb] == -1){
- UNLOCK(mdp);
- THROWF(0, "Asked to free a fragment that is already free. I'm puzzled\n");
- }
-
- if (MC_is_active() && mdp->heapinfo[block].busy_frag.ignore[frag_nb] > 0)
- MC_unignore_heap(ptr, mdp->heapinfo[block].busy_frag.frag_size[frag_nb]);
-
- /* Set size used in the fragment to -1 */
- mdp->heapinfo[block].busy_frag.frag_size[frag_nb] = -1;
- mdp->heapinfo[block].busy_frag.ignore[frag_nb] = 0;
-
- if (mdp->heapinfo[block].busy_frag.nfree ==
- (BLOCKSIZE >> type) - 1) {
- /* If all fragments of this block are free, remove this block from its swag and free the whole block. */
- xbt_swag_remove(&mdp->heapinfo[block],&mdp->fraghead[type]);
-
- /* pretend that this block is used and free it so that it gets properly coalesced with adjacent free blocks */
- mdp->heapinfo[block].type = MMALLOC_TYPE_UNFRAGMENTED;
- mdp->heapinfo[block].busy_block.size = 1;
- mdp->heapinfo[block].busy_block.busy_size = 0;
-
- /* Keep the statistics accurate. */
- mdp -> heapstats.chunks_used++;
- mdp -> heapstats.bytes_used += BLOCKSIZE;
- mdp -> heapstats.chunks_free -= BLOCKSIZE >> type;
- mdp -> heapstats.bytes_free -= BLOCKSIZE;
-
- mfree((void *) mdp, (void *) ADDRESS(block));
- } else if (mdp->heapinfo[block].busy_frag.nfree != 0) {
- /* If some fragments of this block are free, you know what? I'm already happy. */
- ++mdp->heapinfo[block].busy_frag.nfree;
- } else {
- /* No fragments of this block were free before the one we just released,
- * so add this block to the swag and announce that
- it is the first free fragment of this block. */
- mdp->heapinfo[block].busy_frag.nfree = 1;
- mdp->heapinfo[block].freehook.prev = NULL;
- mdp->heapinfo[block].freehook.next = NULL;
-
- xbt_swag_insert(&mdp->heapinfo[block],&mdp->fraghead[type]);
- }
- break;
- }
-}
