X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/bee3400ba6e1daeca869db8753dc4d86bcda28ca..08d324beef1e0fa723013987a98ed7740d2f8343:/src/xbt/mmalloc/mmalloc.c

diff --git a/src/xbt/mmalloc/mmalloc.c b/src/xbt/mmalloc/mmalloc.c
index ab198a97d7..5f13f656f0 100644
--- a/src/xbt/mmalloc/mmalloc.c
+++ b/src/xbt/mmalloc/mmalloc.c
@@ -16,80 +16,88 @@
 
 /* Prototypes for local functions */
 
-static int initialize(struct mdesc *mdp);
-static void *morecore(struct mdesc *mdp, size_t size);
-static void *align(struct mdesc *mdp, size_t size);
-
-/* Aligned allocation.  */
-
+static void initialize(xbt_mheap_t mdp);
+static void *register_morecore(xbt_mheap_t mdp, size_t size);
+static void *align(xbt_mheap_t mdp, size_t size);
+
+/* Allocation aligned on block boundary.
+ *
+ * It never returns NULL, but dies verbosely on error.
+ */
 static void *align(struct mdesc *mdp, size_t size)
 {
   void *result;
   unsigned long int adj;
 
-  result = mdp->morecore(mdp, size);
+  result = mmorecore(mdp, size);
+
+  /* if this reservation does not fill up the last block of our resa,
+   * complete the reservation by also asking for the full lastest block.
+   *
+   * Also, the returned block is aligned to the end of block (but I've
+   * no fucking idea of why, actually -- http://abstrusegoose.com/432 --
+   * but not doing so seems to lead to issues).
+   */
   adj = RESIDUAL(result, BLOCKSIZE);
   if (adj != 0) {
     adj = BLOCKSIZE - adj;
-    mdp->morecore(mdp, adj);
+    mmorecore(mdp, adj);
     result = (char *) result + adj;
   }
   return (result);
 }
 
-/* Set everything up and remember that we have.  */
-
-static int initialize(struct mdesc *mdp)
+/* Finish the initialization of the mheap. If we want to inline it
+ * properly, we need to make the align function publicly visible, too  */
+static void initialize(xbt_mheap_t mdp)
 {
   mdp->heapsize = HEAP / BLOCKSIZE;
   mdp->heapinfo = (malloc_info *)
-      align(mdp, mdp->heapsize * sizeof(malloc_info));
-  if (mdp->heapinfo == NULL) {
-    return (0);
-  }
+    align(mdp, mdp->heapsize * sizeof(malloc_info));
+
   memset((void *) mdp->heapinfo, 0, mdp->heapsize * sizeof(malloc_info));
-  mdp->heapinfo[0].free.size = 0;
-  mdp->heapinfo[0].free.next = mdp->heapinfo[0].free.prev = 0;
+  mdp->heapinfo[0].type=-1;
+  mdp->heapinfo[0].free_block.size = 0;
+  mdp->heapinfo[0].free_block.next = mdp->heapinfo[0].free_block.prev = 0;
   mdp->heapindex = 0;
   mdp->heapbase = (void *) mdp->heapinfo;
   mdp->flags |= MMALLOC_INITIALIZED;
-  return (1);
 }
 
-/* Get neatly aligned memory, initializing or
-   growing the heap info table as necessary. */
-
-static void *morecore(struct mdesc *mdp, size_t size)
+/* Get neatly aligned memory from the low level layers, and register it
+ * into the heap info table as necessary. */
+static void *register_morecore(struct mdesc *mdp, size_t size)
 {
   void *result;
   malloc_info *newinfo, *oldinfo;
   size_t newsize;
 
-  result = align(mdp, size);
-  if (result == NULL) {
-    return (NULL);
-  }
+  result = align(mdp, size); // Never returns NULL
 
-  /* Check if we need to grow the info table.  */
+  /* Check if we need to grow the info table (in a multiplicative manner)  */
   if ((size_t) BLOCK((char *) result + size) > mdp->heapsize) {
+    int it;
+
     newsize = mdp->heapsize;
-    while ((size_t) BLOCK((char *) result + size) > newsize) {
+    while ((size_t) BLOCK((char *) result + size) > newsize)
       newsize *= 2;
-    }
-    newinfo = (malloc_info *) align(mdp, newsize * sizeof(malloc_info));
-    if (newinfo == NULL) {
-      mdp->morecore(mdp, -size);
-      return (NULL);
-    }
-    memset((void *) newinfo, 0, newsize * sizeof(malloc_info));
-    memcpy((void *) newinfo, (void *) mdp->heapinfo,
-           mdp->heapsize * sizeof(malloc_info));
+
+    /* Copy old info into new location */
     oldinfo = mdp->heapinfo;
-    newinfo[BLOCK(oldinfo)].busy.type = 0;
-    newinfo[BLOCK(oldinfo)].busy.info.size
-        = BLOCKIFY(mdp->heapsize * sizeof(malloc_info));
+    newinfo = (malloc_info *) align(mdp, newsize * sizeof(malloc_info));
+    memset(newinfo, 0, newsize * sizeof(malloc_info));
+    memcpy(newinfo, oldinfo, mdp->heapsize * sizeof(malloc_info));
     mdp->heapinfo = newinfo;
-    __mmalloc_free(mdp, (void *) oldinfo);
+
+    /* mark the space previously occupied by the block info as free by first marking it
+     * as occupied in the regular way, and then freing it */
+    for (it=0; it<BLOCKIFY(mdp->heapsize * sizeof(malloc_info)); it++)
+      newinfo[BLOCK(oldinfo)+it].type = 0;
+
+    newinfo[BLOCK(oldinfo)].busy_block.size = BLOCKIFY(mdp->heapsize * sizeof(malloc_info));
+    newinfo[BLOCK(oldinfo)].busy_block.busy_size = size;
+    newinfo[BLOCK(oldinfo)].busy_block.bt_size = 0;// FIXME setup the backtrace
+    mfree(mdp, (void *) oldinfo);
     mdp->heapsize = newsize;
   }
 
@@ -99,37 +107,28 @@ static void *morecore(struct mdesc *mdp, size_t size)
 
 /* Allocate memory from the heap.  */
 
-void *mmalloc(void *md, size_t size)
+void *mmalloc(xbt_mheap_t mdp, size_t size)
 {
-  struct mdesc *mdp;
   void *result;
   size_t block, blocks, lastblocks, start;
   register size_t i;
   struct list *next;
   register size_t log;
+  int it;
 
-  /* Work even if the user was stupid enough to ask a 0-byte block, ie return a valid block that can be realloced or freed
-   * glibc malloc does not use this trick but return a constant pointer, but my hack is quicker to implement ;)
-   */
-  if (size == 0)
-    size = 1;
+  size_t requested_size = size; // The amount of memory requested by user, for real
 
-  mdp = MD_TO_MDP(md);
-//  printf("(%s) Mallocing %d bytes on %p (default: %p)...",xbt_thread_self_name(),size,mdp,__mmalloc_default_mdp);fflush(stdout);
-
-  if (mdp->mmalloc_hook != NULL) {
-    return mdp->mmalloc_hook(md, size);
-  }
+  /* Work even if the user was stupid enough to ask a ridicullously small block (even 0-length),
+   *    ie return a valid block that can be realloced and freed.
+   * glibc malloc does not use this trick but return a constant pointer, but we need to enlist the free fragments later on.
+   */
+  if (size < SMALLEST_POSSIBLE_MALLOC)
+    size = SMALLEST_POSSIBLE_MALLOC;
 
-  if (!(mdp->flags & MMALLOC_INITIALIZED)) {
-    if (!initialize(mdp)) {
-      return (NULL);
-    }
-  }
+  //  printf("(%s) Mallocing %d bytes on %p (default: %p)...",xbt_thread_self_name(),size,mdp,__mmalloc_default_mdp);fflush(stdout);
 
-  if (size < sizeof(struct list)) {
-    size = sizeof(struct list);
-  }
+  if (!(mdp->flags & MMALLOC_INITIALIZED))
+    initialize(mdp);
 
   /* Determine the allocation policy based on the request size.  */
   if (size <= BLOCKSIZE / 2) {
@@ -148,34 +147,43 @@ void *mmalloc(void *md, size_t size)
       /* There are free fragments of this size.
          Pop a fragment out of the fragment list and return it.
          Update the block's nfree and first counters. */
+      int frag_nb;
       result = (void *) next;
+      block = BLOCK(result);
+
+      frag_nb = RESIDUAL(result, BLOCKSIZE) >> log;
+      mdp->heapinfo[block].busy_frag.frag_size[frag_nb] = requested_size;
+      xbt_backtrace_no_malloc(mdp->heapinfo[block].busy_frag.bt[frag_nb],XBT_BACKTRACE_SIZE);
+
       next->prev->next = next->next;
       if (next->next != NULL) {
         next->next->prev = next->prev;
       }
-      block = BLOCK(result);
-      if (--mdp->heapinfo[block].busy.info.frag.nfree != 0) {
-        mdp->heapinfo[block].busy.info.frag.first =
-            RESIDUAL(next->next, BLOCKSIZE) >> log;
+      if (--mdp->heapinfo[block].busy_frag.nfree != 0) {
+        mdp->heapinfo[block].busy_frag.first =
+          RESIDUAL(next->next, BLOCKSIZE) >> log;
       }
 
       /* Update the statistics.  */
-      mdp->heapstats.chunks_used++;
-      mdp->heapstats.bytes_used += 1 << log;
-      mdp->heapstats.chunks_free--;
-      mdp->heapstats.bytes_free -= 1 << log;
+      mdp -> heapstats.chunks_used++;
+      mdp -> heapstats.bytes_used += 1 << log;
+      mdp -> heapstats.chunks_free--;
+      mdp -> heapstats.bytes_free -= 1 << log;
+
+      memset(result, 0, requested_size);
+      
     } else {
       /* No free fragments of the desired size, so get a new block
          and break it into fragments, returning the first.  */
       //printf("(%s) No free fragment...",xbt_thread_self_name());
-      result = mmalloc(md, BLOCKSIZE);
-      //printf("(%s) Fragment: %p...",xbt_thread_self_name(),result);
-      if (result == NULL) {
-        return (NULL);
-      }
 
-      /* Link all fragments but the first into the free list.  */
+      result = mmalloc(mdp, BLOCKSIZE); // does not return NULL
+      memset(result, 0, requested_size);
+
+      /* Link all fragments but the first into the free list, and mark their requested size to 0.  */
+      block = BLOCK(result);
       for (i = 1; i < (size_t) (BLOCKSIZE >> log); ++i) {
+        mdp->heapinfo[block].busy_frag.frag_size[i] = 0;
         next = (struct list *) ((char *) result + (i << log));
         next->next = mdp->fraghead[log].next;
         next->prev = &mdp->fraghead[log];
@@ -184,16 +192,17 @@ void *mmalloc(void *md, size_t size)
           next->next->prev = next;
         }
       }
-
+      mdp->heapinfo[block].busy_frag.frag_size[0] = requested_size;
+      xbt_backtrace_no_malloc(mdp->heapinfo[block].busy_frag.bt[0],XBT_BACKTRACE_SIZE);
+      
       /* Initialize the nfree and first counters for this block.  */
-      block = BLOCK(result);
-      mdp->heapinfo[block].busy.type = log;
-      mdp->heapinfo[block].busy.info.frag.nfree = i - 1;
-      mdp->heapinfo[block].busy.info.frag.first = i - 1;
+      mdp->heapinfo[block].type = log;
+      mdp->heapinfo[block].busy_frag.nfree = i - 1;
+      mdp->heapinfo[block].busy_frag.first = i - 1;
 
-      mdp->heapstats.chunks_free += (BLOCKSIZE >> log) - 1;
-      mdp->heapstats.bytes_free += BLOCKSIZE - (1 << log);
-      mdp->heapstats.bytes_used -= BLOCKSIZE - (1 << log);
+      mdp -> heapstats.chunks_free += (BLOCKSIZE >> log) - 1;
+      mdp -> heapstats.bytes_free += BLOCKSIZE - (1 << log);
+      mdp -> heapstats.bytes_used -= BLOCKSIZE - (1 << log);
     }
   } else {
     /* Large allocation to receive one or more blocks.
@@ -202,70 +211,81 @@ void *mmalloc(void *md, size_t size)
        space we will have to get more memory from the system.  */
     blocks = BLOCKIFY(size);
     start = block = MALLOC_SEARCH_START;
-    while (mdp->heapinfo[block].free.size < blocks) {
-      block = mdp->heapinfo[block].free.next;
+    while (mdp->heapinfo[block].free_block.size < blocks) {
+      if (mdp->heapinfo[block].type >=0) { // Don't trust xbt_die and friends in malloc-level library, you fool!
+        fprintf(stderr,"Internal error: found a free block not marked as such (block=%lu type=%lu). Please report this bug.\n",(unsigned long)block,(unsigned long)mdp->heapinfo[block].type);
+        abort();
+      }
+
+      block = mdp->heapinfo[block].free_block.next;
       if (block == start) {
         /* Need to get more from the system.  Check to see if
            the new core will be contiguous with the final free
            block; if so we don't need to get as much.  */
-        block = mdp->heapinfo[0].free.prev;
-        lastblocks = mdp->heapinfo[block].free.size;
+        block = mdp->heapinfo[0].free_block.prev;
+        lastblocks = mdp->heapinfo[block].free_block.size;
         if (mdp->heaplimit != 0 &&
             block + lastblocks == mdp->heaplimit &&
-            mdp->morecore(mdp, 0) == ADDRESS(block + lastblocks) &&
-            (morecore(mdp, (blocks - lastblocks) * BLOCKSIZE)) != NULL) {
+            mmorecore(mdp, 0) == ADDRESS(block + lastblocks) &&
+            (register_morecore(mdp, (blocks - lastblocks) * BLOCKSIZE)) != NULL) {
           /* Which block we are extending (the `final free
              block' referred to above) might have changed, if
              it got combined with a freed info table.  */
-          block = mdp->heapinfo[0].free.prev;
+          block = mdp->heapinfo[0].free_block.prev;
 
-          mdp->heapinfo[block].free.size += (blocks - lastblocks);
-          mdp->heapstats.bytes_free += (blocks - lastblocks) * BLOCKSIZE;
+          mdp->heapinfo[block].free_block.size += (blocks - lastblocks);
           continue;
         }
-        result = morecore(mdp, blocks * BLOCKSIZE);
-        if (result == NULL) {
-          return (NULL);
-        }
+        result = register_morecore(mdp, blocks * BLOCKSIZE);
+        memset(result, 0, requested_size);
+
         block = BLOCK(result);
-        mdp->heapinfo[block].busy.type = 0;
-        mdp->heapinfo[block].busy.info.size = blocks;
-        mdp->heapstats.chunks_used++;
-        mdp->heapstats.bytes_used += blocks * BLOCKSIZE;
-        return (result);
+        for (it=0;it<blocks;it++)
+          mdp->heapinfo[block+it].type = 0;
+        mdp->heapinfo[block].busy_block.size = blocks;
+        mdp->heapinfo[block].busy_block.busy_size = requested_size;
+        mdp->heapinfo[block].busy_block.bt_size=xbt_backtrace_no_malloc(mdp->heapinfo[block].busy_block.bt,XBT_BACKTRACE_SIZE);
+        mdp -> heapstats.chunks_used++;
+        mdp -> heapstats.bytes_used += blocks * BLOCKSIZE;
+        return result;
       }
+      /* Need large block(s), but found some in the existing heap */
     }
 
     /* At this point we have found a suitable free list entry.
        Figure out how to remove what we need from the list. */
     result = ADDRESS(block);
-    if (mdp->heapinfo[block].free.size > blocks) {
+    if (mdp->heapinfo[block].free_block.size > blocks) {
       /* The block we found has a bit left over,
          so relink the tail end back into the free list. */
-      mdp->heapinfo[block + blocks].free.size
-          = mdp->heapinfo[block].free.size - blocks;
-      mdp->heapinfo[block + blocks].free.next
-          = mdp->heapinfo[block].free.next;
-      mdp->heapinfo[block + blocks].free.prev
-          = mdp->heapinfo[block].free.prev;
-      mdp->heapinfo[mdp->heapinfo[block].free.prev].free.next
-          = mdp->heapinfo[mdp->heapinfo[block].free.next].free.prev
-          = mdp->heapindex = block + blocks;
+      mdp->heapinfo[block + blocks].free_block.size
+        = mdp->heapinfo[block].free_block.size - blocks;
+      mdp->heapinfo[block + blocks].free_block.next
+        = mdp->heapinfo[block].free_block.next;
+      mdp->heapinfo[block + blocks].free_block.prev
+        = mdp->heapinfo[block].free_block.prev;
+      mdp->heapinfo[mdp->heapinfo[block].free_block.prev].free_block.next
+        = mdp->heapinfo[mdp->heapinfo[block].free_block.next].free_block.prev
+        = mdp->heapindex = block + blocks;
     } else {
       /* The block exactly matches our requirements,
          so just remove it from the list. */
-      mdp->heapinfo[mdp->heapinfo[block].free.next].free.prev
-          = mdp->heapinfo[block].free.prev;
-      mdp->heapinfo[mdp->heapinfo[block].free.prev].free.next
-          = mdp->heapindex = mdp->heapinfo[block].free.next;
-      mdp->heapstats.chunks_free--;
+      mdp->heapinfo[mdp->heapinfo[block].free_block.next].free_block.prev
+        = mdp->heapinfo[block].free_block.prev;
+      mdp->heapinfo[mdp->heapinfo[block].free_block.prev].free_block.next
+        = mdp->heapindex = mdp->heapinfo[block].free_block.next;
     }
 
-    mdp->heapinfo[block].busy.type = 0;
-    mdp->heapinfo[block].busy.info.size = blocks;
-    mdp->heapstats.chunks_used++;
-    mdp->heapstats.bytes_used += blocks * BLOCKSIZE;
-    mdp->heapstats.bytes_free -= blocks * BLOCKSIZE;
+    for (it=0;it<blocks;it++)
+      mdp->heapinfo[block+it].type = 0;
+    mdp->heapinfo[block].busy_block.size = blocks;
+    mdp->heapinfo[block].busy_block.busy_size = requested_size;
+    //mdp->heapinfo[block].busy_block.bt_size = 0;
+    mdp->heapinfo[block].busy_block.bt_size = xbt_backtrace_no_malloc(mdp->heapinfo[block].busy_block.bt,XBT_BACKTRACE_SIZE);
+
+    mdp -> heapstats.chunks_used++;
+    mdp -> heapstats.bytes_used += blocks * BLOCKSIZE;
+    mdp -> heapstats.bytes_free -= blocks * BLOCKSIZE;
   }
   //printf("(%s) Done mallocing. Result is %p\n",xbt_thread_self_name(),result);fflush(stdout);
   return (result);