[mmalloc] Expand the junkarea

[simgrid.git] / src / xbt / mmalloc / mm_legacy.c

diff --git a/src/xbt/mmalloc/mm_legacy.c b/src/xbt/mmalloc/mm_legacy.c
index 3c8e301..20a609a 100644 (file)
--- a/src/xbt/mmalloc/mm_legacy.c
+++ b/src/xbt/mmalloc/mm_legacy.c
@@ -57,11 +57,11 @@ static void mm_gnuld_legacy_init(void) { /* This function is called from mmalloc
  */
 static int allocated_junk = 0; /* keep track of many blocks of our little area was already given to someone */
 #define JUNK_SIZE 8
-#define MAX_JUNK_AREAS (32 * 1024 / JUNK_SIZE)
+#define MAX_JUNK_AREAS (64 * 1024 / JUNK_SIZE)
 static char junkareas[MAX_JUNK_AREAS][JUNK_SIZE];
 
 /* This version use mmalloc if there is a current heap, or the legacy implem if not */
-void *malloc(size_t n) {
+static void *malloc_or_calloc(size_t n, int setzero) {
   xbt_mheap_t mdp = __mmalloc_current_heap;
   void *ret;
 #ifdef MM_LEGACY_VERBOSE
@@ -73,14 +73,17 @@ void *malloc(size_t n) {
     LOCK(mdp);
     ret = mmalloc(mdp, n);
     UNLOCK(mdp);
+    // This was already done by mmalloc:
+    if (mdp->options & XBT_MHEAP_OPTION_MEMSET) {
+      setzero = 0;
+    }
 #ifdef MM_LEGACY_VERBOSE
     if (!warned_mmalloc) {
       fprintf(stderr,"Using mmalloc; enabling the model-checker in cmake may have a bad impact on your simulation performance\n");
       warned_mmalloc = 1;
     }
 #endif
-  } else {
-    if (!real_malloc) {
+  } else if (!real_malloc) {
       size_t needed_areas = n / JUNK_SIZE;
       if(needed_areas * JUNK_SIZE != n) needed_areas++;
       if (allocated_junk+needed_areas>=MAX_JUNK_AREAS) {
@@ -90,9 +93,10 @@ void *malloc(size_t n) {
       } else {
         size_t i = allocated_junk;
         allocated_junk += needed_areas;
-        return junkareas[i];
+        ret = junkareas[i];
       }
     }
+  else {
 #ifdef MM_LEGACY_VERBOSE
     if (!warned_raw) {
       fprintf(stderr,"Using system malloc after interception; you seem to be currently model-checking\n");
@@ -101,15 +105,20 @@ void *malloc(size_t n) {
 #endif
     ret = real_malloc(n);
   }
+  if (ret && setzero) {
+    memset(ret, 0, n);
+  }
   return ret;
 }
 
+void *malloc(size_t n)
+{
+  return malloc_or_calloc(n, 0);
+}
 
 void *calloc(size_t nmemb, size_t size)
 {
-  void *ret = malloc(nmemb*size);
-  memset(ret, 0, nmemb * size);
-  return ret;
+  return malloc_or_calloc(nmemb*size, 1);
 }
 
 void *realloc(void *p, size_t s)
@@ -132,7 +141,9 @@ void free(void *p)
 {
   if (p==NULL)
     return;
-  if (p<=(void*)junkareas || p>(void*)(junkareas[MAX_JUNK_AREAS]) ) {
+  if (p<(void*)junkareas || p>=(void*)(junkareas[MAX_JUNK_AREAS]) ) {
+    // main use case
+
     xbt_mheap_t mdp = __mmalloc_current_heap;
 
     if (mdp) {
@@ -142,10 +153,16 @@ void free(void *p)
     } else {
       real_free(p);
     }
-  } else if(allocated_junk && p==junkareas[allocated_junk-1]) {
-    allocated_junk--;
   } else {
-    // Leaked memory.
+    // We are in the junkarea.
+    // This area is used to allocate memory at initilization time.
+
+    if(allocated_junk && p==junkareas[allocated_junk-1]) {
+      // Last junkarea. We can reuse it.
+      allocated_junk--;
+    } else {
+      // We currently cannot reuse freed junkareas in the general case.
+    }
   }
 }