From: Martin Quinson <martin.quinson@loria.fr>
Date: Thu, 2 Feb 2012 20:08:51 +0000 (+0100)
Subject: improve the doc to reflect recent changes (and we already have the actual size of... 
X-Git-Tag: exp_20120216~77
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/027d955aa752674c7d524a3bba004aaa7af1d0dc?hp=72a8adff27c51a64b9e2e95e561d8d6950310568

improve the doc to reflect recent changes (and we already have the actual size of blocks)
---

diff --git a/src/xbt/mmalloc/mmprivate.h b/src/xbt/mmalloc/mmprivate.h
index e886092f75..b87c21d8b2 100644
--- a/src/xbt/mmalloc/mmprivate.h
+++ b/src/xbt/mmalloc/mmprivate.h
@@ -95,6 +95,11 @@ const char *xbt_thread_self_name(void);
  *    When looking for free blocks, we traverse the mdp->heapinfo looking
  *    for a cluster of free blocks that would be large enough.
  *
+ *    The size of the cluster is only to be trusted in the first block of the cluster.
+ *    If the cluster results of the fusion of several clusters, the previously first
+ *    block of their cluster will have partial data. The only information kept consistent over
+ *    all blocks of the clusters is their type (== -1).
+ *
  * Note that there is no way to determine if the block is free or busy by exploring
  * this structure only. It wasn't intended to be crawled for comparison and we should fix it (TODO).
  *
@@ -103,9 +108,8 @@ const char *xbt_thread_self_name(void);
  * I retrieve the first block of my cluster.
  *
  * TODO:
- *  - add an indication of the requested size in the busy.block structure
- *  - add the same for each fragments
- *  - make room to store the backtrace of where the fragment were malloced, too.
+ *  - add an indication of the requested size in each fragment, similarly to busy_block.busy_size
+ *  - make room to store the backtrace of where the blocks and fragment were malloced, too.
  */
 typedef struct {
 	int type; /*  0: busy large block
@@ -119,7 +123,7 @@ typedef struct {
 		} busy_frag;
 		struct {
 			size_t size; /* Size (in blocks) of a large cluster.  */
-			size_t busy_size;
+			size_t busy_size; /* Actually used space, in bytes */
 		} busy_block;
 		/* Heap information for a free block (that may be the first of a free cluster).  */
 		struct {
diff --git a/src/xbt/mmalloc/mrealloc.c b/src/xbt/mmalloc/mrealloc.c
index ea4d7f6878..5928d132de 100644
--- a/src/xbt/mmalloc/mrealloc.c
+++ b/src/xbt/mmalloc/mrealloc.c
@@ -26,6 +26,7 @@ void *mrealloc(xbt_mheap_t mdp, void *ptr, size_t size)
   int type;
   size_t block, blocks, oldlimit;
 
+  /* Only keep real realloc and hidden malloc and free to the relevant functions */
   if (size == 0) {
     mfree(mdp, ptr);
     return mmalloc(mdp, 0);
@@ -33,7 +34,6 @@ void *mrealloc(xbt_mheap_t mdp, void *ptr, size_t size)
     return mmalloc(mdp, size);
   }
 
-
   //printf("(%s)realloc %p to %d...",xbt_thread_self_name(),ptr,(int)size);
 
   if ((char *) ptr < (char *) mdp->heapbase || BLOCK(ptr) > mdp->heapsize) {