Updated to fedora-glibc-20041004T0747cvs/fedora-glibc-2_3_3-64

2 files changed, 65 insertions, 17 deletions

diff --git a/malloc/arena.c b/malloc/arena.c
index 3adfbc45f8..00f40971f3 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -550,6 +550,16 @@ dump_heap(heap) heap_info *heap;
 
 #endif /* MALLOC_DEBUG > 1 */
 
+/* If consecutive mmap (0, HEAP_MAX_SIZE << 1, ...) calls return decreasing
+   addresses as opposed to increasing, new_heap would badly fragment the
+   address space.  In that case remember the second HEAP_MAX_SIZE part
+   aligned to HEAP_MAX_SIZE from last mmap (0, HEAP_MAX_SIZE << 1, ...)
+   call (if it is already aligned) and try to reuse it next time.  We need
+   no locking for it, as kernel ensures the atomicity for us - worst case
+   we'll call mmap (addr, HEAP_MAX_SIZE, ...) for some value of addr in
+   multiple threads, but only one will succeed.  */
+static char *aligned_heap_area;
+
 /* Create a new heap.  size is automatically rounded up to a multiple
    of the page size. */
 
@@ -580,21 +590,38 @@ new_heap(size, top_pad) size_t size, top_pad;
      No swap space needs to be reserved for the following large
      mapping (on Linux, this is the case for all non-writable mappings
      anyway). */
-  p1 = (char *)MMAP(0, HEAP_MAX_SIZE<<1, PROT_NONE, MAP_PRIVATE|MAP_NORESERVE);
-  if(p1 != MAP_FAILED) {
-    p2 = (char *)(((unsigned long)p1 + (HEAP_MAX_SIZE-1)) & ~(HEAP_MAX_SIZE-1));
-    ul = p2 - p1;
-    munmap(p1, ul);
-    munmap(p2 + HEAP_MAX_SIZE, HEAP_MAX_SIZE - ul);
-  } else {
-    /* Try to take the chance that an allocation of only HEAP_MAX_SIZE
-       is already aligned. */
-    p2 = (char *)MMAP(0, HEAP_MAX_SIZE, PROT_NONE, MAP_PRIVATE|MAP_NORESERVE);
-    if(p2 == MAP_FAILED)
-      return 0;
-    if((unsigned long)p2 & (HEAP_MAX_SIZE-1)) {
+  p2 = MAP_FAILED;
+  if(aligned_heap_area) {
+    p2 = (char *)MMAP(aligned_heap_area, HEAP_MAX_SIZE, PROT_NONE,
+		      MAP_PRIVATE|MAP_NORESERVE);
+    aligned_heap_area = NULL;
+    if (p2 != MAP_FAILED && ((unsigned long)p2 & (HEAP_MAX_SIZE-1))) {
       munmap(p2, HEAP_MAX_SIZE);
-      return 0;
+      p2 = MAP_FAILED;
+    }
+  }
+  if(p2 == MAP_FAILED) {
+    p1 = (char *)MMAP(0, HEAP_MAX_SIZE<<1, PROT_NONE,
+		      MAP_PRIVATE|MAP_NORESERVE);
+    if(p1 != MAP_FAILED) {
+      p2 = (char *)(((unsigned long)p1 + (HEAP_MAX_SIZE-1))
+		    & ~(HEAP_MAX_SIZE-1));
+      ul = p2 - p1;
+      if (ul)
+	munmap(p1, ul);
+      else
+	aligned_heap_area = p2 + HEAP_MAX_SIZE;
+      munmap(p2 + HEAP_MAX_SIZE, HEAP_MAX_SIZE - ul);
+    } else {
+      /* Try to take the chance that an allocation of only HEAP_MAX_SIZE
+	 is already aligned. */
+      p2 = (char *)MMAP(0, HEAP_MAX_SIZE, PROT_NONE, MAP_PRIVATE|MAP_NORESERVE);
+      if(p2 == MAP_FAILED)
+	return 0;
+      if((unsigned long)p2 & (HEAP_MAX_SIZE-1)) {
+	munmap(p2, HEAP_MAX_SIZE);
+	return 0;
+      }
     }
   }
   if(mprotect(p2, size, PROT_READ|PROT_WRITE) != 0) {
@@ -644,7 +671,12 @@ grow_heap(h, diff) heap_info *h; long diff;
 
 /* Delete a heap. */
 
-#define delete_heap(heap) munmap((char*)(heap), HEAP_MAX_SIZE)
+#define delete_heap(heap) \
+  do {								\
+    if ((char *)(heap) + HEAP_MAX_SIZE == aligned_heap_area)	\
+      aligned_heap_area = NULL;					\
+    munmap((char*)(heap), HEAP_MAX_SIZE);			\
+  } while (0)
 
 static int
 internal_function
diff --git a/malloc/malloc.c b/malloc/malloc.c
index dcc54c46f1..a41171490a 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -1709,7 +1709,7 @@ struct malloc_chunk {
     chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             |             Size of previous chunk, if allocated            | |
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-            |             Size of chunk, in bytes                         |P|
+            |             Size of chunk, in bytes                       |M|P|
       mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             |             User data starts here...                          .
             .                                                               .
@@ -1771,7 +1771,7 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         MINSIZE bytes long, it is replenished.
 
      2. Chunks allocated via mmap, which have the second-lowest-order
-        bit (IS_MMAPPED) set in their size fields.  Because they are
+        bit M (IS_MMAPPED) set in their size fields.  Because they are
         allocated one-by-one, each must contain its own trailing size field.
 
 */
@@ -3530,6 +3530,13 @@ public_vALLOc(size_t bytes)
 
   if(__malloc_initialized < 0)
     ptmalloc_init ();
+
+  __malloc_ptr_t (*hook) __MALLOC_PMT ((size_t, size_t,
+					__const __malloc_ptr_t)) =
+    __memalign_hook;
+  if (hook != NULL)
+    return (*hook)(mp_.pagesize, bytes, RETURN_ADDRESS (0));
+
   arena_get(ar_ptr, bytes + mp_.pagesize + MINSIZE);
   if(!ar_ptr)
     return 0;
@@ -3546,6 +3553,15 @@ public_pVALLOc(size_t bytes)
 
   if(__malloc_initialized < 0)
     ptmalloc_init ();
+
+  __malloc_ptr_t (*hook) __MALLOC_PMT ((size_t, size_t,
+					__const __malloc_ptr_t)) =
+    __memalign_hook;
+  if (hook != NULL)
+    return (*hook)(mp_.pagesize,
+		   (bytes + mp_.pagesize - 1) & ~(mp_.pagesize - 1),
+		   RETURN_ADDRESS (0));
+
   arena_get(ar_ptr, bytes + 2*mp_.pagesize + MINSIZE);
   p = _int_pvalloc(ar_ptr, bytes);
   (void)mutex_unlock(&ar_ptr->mutex);