/* -----------------------------------------------------------------------------
- * $Id: MBlock.c,v 1.34 2002/10/27 21:46:27 wolfgang Exp $
+ * $Id: MBlock.c,v 1.41 2002/11/26 07:02:04 mthomas Exp $
*
* (c) The GHC Team 1998-1999
*
The MBlock Map: provides our implementation of HEAP_ALLOCED()
-------------------------------------------------------------------------- */
-StgWord8 mblock_map[4096]; // initially all zeros
-
-static void
-mblockIsHeap (void *p)
-{
- mblock_map[((StgWord)p & ~MBLOCK_MASK) >> MBLOCK_SHIFT] = 1;
-}
+#ifdef MBLOCK_MAP_SIZE
+StgWord8 mblock_map[MBLOCK_MAP_SIZE]; // initially all zeros
+#endif
/* -----------------------------------------------------------------------------
Allocate new mblock(s)
if(!addr || err) // try to allocate anywhere
err = vm_allocate(mach_task_self(),(vm_address_t*) &ret, size, TRUE);
- if(err)
- ret = (void*) -1;
+ if(err) // don't know what the error codes mean exactly
+ barf("memory allocation failed (requested %d bytes)", size);
else
vm_protect(mach_task_self(),ret,size,FALSE,VM_PROT_READ|VM_PROT_WRITE);
#else
- ret = mmap(addr, size, PROT_READ | PROT_WRITE,
+ ret = mmap(addr, size, PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_ANON | MAP_PRIVATE, -1, 0);
#endif
+ if (ret == (void *)-1) {
+ if (errno == ENOMEM) {
+ barf("out of memory (requested %d bytes)", size);
+ } else {
+ barf("getMBlock: mmap failed");
+ }
+ }
+
return ret;
-}
+}
// Implements the general case: allocate a chunk of memory of 'size'
// mblocks.
// it (unmap the rest).
size += MBLOCK_SIZE;
ret = my_mmap(0, size);
- if (ret == (void *)-1) {
- barf("gen_map_mblocks: mmap failed");
- }
// unmap the slop bits around the chunk we allocated
slop = (W_)ret & MBLOCK_MASK;
barf("gen_map_mblocks: munmap failed");
}
+ // ToDo: if we happened to get an aligned block, then don't
+ // unmap the excess, just use it.
+
// next time, try after the block we just got.
ret += MBLOCK_SIZE - slop;
return ret;
ret = gen_map_mblocks(size);
} else {
ret = my_mmap(next_request, size);
-
- if (ret == (void *)-1) {
- if (errno == ENOMEM) {
- belch("out of memory (requested %d bytes)", n * BLOCK_SIZE);
- stg_exit(EXIT_FAILURE);
- } else {
- barf("getMBlock: mmap failed");
- }
- }
if (((W_)ret & MBLOCK_MASK) != 0) {
// misaligned block!
#ifdef DEBUG
- belch("getMBlock: misaligned block %p returned when allocating %d megablock(s) at %p", ret, n, next_request);
+ belch("warning: getMBlock: misaligned block %p returned when allocating %d megablock(s) at %p", ret, n, next_request);
#endif
// unmap this block...
}
// Next time, we'll try to allocate right after the block we just got.
+ // ToDo: check that we haven't already grabbed the memory at next_request
next_request = ret + size;
IF_DEBUG(gc,fprintf(stderr,"Allocated %d megablock(s) at %p\n",n,ret));
// fill in the table
for (i = 0; i < n; i++) {
- mblockIsHeap( ret + i * MBLOCK_SIZE );
+ MARK_HEAP_ALLOCED( ret + i * MBLOCK_SIZE );
}
mblocks_allocated += n;
// fill in the table
for (i = 0; i < n; i++) {
- mblockIsHeap( ret + i * MBLOCK_SIZE );
+ MARK_HEAP_ALLOCED ( ret + i * MBLOCK_SIZE );
}
return ret;