X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/87817af89b2262a403386b38a0ec95388a6df5ad..6d215aa449fe86894819be267aa2ae30cb5b151c:/src/xbt/mmalloc/mfree.c?ds=inline

diff --git a/src/xbt/mmalloc/mfree.c b/src/xbt/mmalloc/mfree.c
index db57be44c5..c750d9ad3c 100644
--- a/src/xbt/mmalloc/mfree.c
+++ b/src/xbt/mmalloc/mfree.c
@@ -15,27 +15,42 @@
 /* Return memory to the heap.
    Like `mfree' but don't call a mfree_hook if there is one.  */
 
-void __mmalloc_free(struct mdesc *mdp, void *ptr)
+/* Return memory to the heap.  */
+void mfree(struct mdesc *mdp, void *ptr)
 {
   int type;
   size_t block;
   register size_t i;
   struct list *prev, *next;
+  int it;
+
+  if (ptr == NULL)
+	  return;
 
   block = BLOCK(ptr);
 
   if ((char *) ptr < (char *) mdp->heapbase || block > mdp->heapsize) {
-    printf("Ouch, this pointer is not mine. I refuse to free it.\n");
-    return;
+    fprintf(stderr,"Ouch, this pointer is not mine. I refuse to free it. I refuse it to death!!\n");
+    abort();
   }
 
 
   type = mdp->heapinfo[block].type;
-  if (type<0)
-      THROWF(arg_error,0,"Asked to free a fragment in a block that is already free. I'm puzzled");
 
   switch (type) {
+  case -1: /* Already free */
+    fprintf(stderr,"Asked to free a fragment in a block that is already free. I'm puzzled\n");
+    abort();
+    break;
+
   case 0:
+     /* 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;
+
     /* 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.  */
@@ -54,16 +69,38 @@ void __mmalloc_free(struct mdesc *mdp, void *ptr)
 
     /* 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 = -1;
+      }
+
       block = i;
     } else {
+      //fprintf(stderr,"Free block %d to %d (as a new chunck)\n",block,block+mdp->heapinfo[block].busy_block.size);
       /* 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 = -1;
+      }
     }
 
     /* Now that the block is linked in, see if we can coalesce it
@@ -76,6 +113,7 @@ void __mmalloc_free(struct mdesc *mdp, void *ptr)
       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.  */
@@ -100,6 +138,13 @@ void __mmalloc_free(struct mdesc *mdp, void *ptr)
     break;
 
   default:
+    /* 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;
+
+    
     /* Get the address of the first free fragment in this block.  */
     prev = (struct list *)
         ((char *) ADDRESS(block) +
@@ -117,10 +162,17 @@ void __mmalloc_free(struct mdesc *mdp, void *ptr)
       if (next != NULL) {
         next->prev = prev->prev;
       }
+      /* pretend that this block is used and free it so that it gets properly coalesced with adjacent free blocks */
       mdp->heapinfo[block].type = 0;
       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, link this
@@ -135,8 +187,8 @@ void __mmalloc_free(struct mdesc *mdp, void *ptr)
       }
       ++mdp->heapinfo[block].busy_frag.nfree;
     } else {
-      /* No fragments of this block are free, so link this
-         fragment into the fragment list and announce that
+      /* No fragments of this block were free before the one we just released,
+       * so link this fragment into the fragment list and announce that
          it is the first free fragment of this block. */
       prev = (struct list *) ptr;
       mdp->heapinfo[block].busy_frag.nfree = 1;
@@ -152,11 +204,3 @@ void __mmalloc_free(struct mdesc *mdp, void *ptr)
     break;
   }
 }
-
-/* Return memory to the heap.  */
-
-void mfree(xbt_mheap_t mdp, void *ptr)
-{
-  if (ptr != NULL)
-    __mmalloc_free(mdp, ptr);
-}