* modified is included with the above copyright notice.
*/
-#define DEBUG
-#undef DEBUG
+/* #define DEBUG */
#include <stdio.h>
-#include "gc_priv.h"
+#include "private/gc_priv.h"
+GC_bool GC_use_entire_heap = 0;
/*
* Free heap blocks are kept on one of several free lists,
struct hblk * GC_hblkfreelist[N_HBLK_FLS+1] = { 0 };
+#ifndef USE_MUNMAP
+
+ word GC_free_bytes[N_HBLK_FLS+1] = { 0 };
+ /* Number of free bytes on each list. */
+
+ /* Is bytes + the number of free bytes on lists n .. N_HBLK_FLS */
+ /* > GC_max_large_allocd_bytes? */
+# ifdef __GNUC__
+ __inline__
+# endif
+ static GC_bool GC_enough_large_bytes_left(bytes,n)
+ word bytes;
+ int n;
+ {
+ int i;
+ for (i = N_HBLK_FLS; i >= n; --i) {
+ bytes += GC_free_bytes[i];
+ if (bytes > GC_max_large_allocd_bytes) return TRUE;
+ }
+ return FALSE;
+ }
+
+# define INCR_FREE_BYTES(n, b) GC_free_bytes[n] += (b);
+
+# define FREE_ASSERT(e) GC_ASSERT(e)
+
+#else /* USE_MUNMAP */
+
+# define INCR_FREE_BYTES(n, b)
+# define FREE_ASSERT(e)
+
+#endif /* USE_MUNMAP */
+
/* Map a number of blocks to the appropriate large block free list index. */
int GC_hblk_fl_from_blocks(blocks_needed)
word blocks_needed;
}
-# define HBLK_IS_FREE(hdr) ((hdr) -> hb_map == GC_invalid_map)
# define PHDR(hhdr) HDR(hhdr -> hb_prev)
# define NHDR(hhdr) HDR(hhdr -> hb_next)
for (i = 0; i <= N_HBLK_FLS; ++i) {
h = GC_hblkfreelist[i];
- if (0 != h) GC_printf1("Free list %ld:\n", (unsigned long)i);
+# ifdef USE_MUNMAP
+ if (0 != h) GC_printf1("Free list %ld:\n",
+ (unsigned long)i);
+# else
+ if (0 != h) GC_printf2("Free list %ld (Total size %ld):\n",
+ (unsigned long)i,
+ (unsigned long)GC_free_bytes[i]);
+# endif
while (h != 0) {
hhdr = HDR(h);
sz = hhdr -> hb_sz;
h = hhdr -> hb_next;
}
}
- if (total_free != GC_large_free_bytes) {
+# ifndef USE_MUNMAP
+ if (total_free != GC_large_free_bytes) {
GC_printf1("GC_large_free_bytes = %lu (INCONSISTENT!!)\n",
(unsigned long) GC_large_free_bytes);
- }
+ }
+# endif
GC_printf1("Total of %lu bytes on free list\n", (unsigned long)total_free);
}
hhdr = HDR(p);
GC_printf1("\t0x%lx ", (unsigned long)p);
if (IS_FORWARDING_ADDR_OR_NIL(hhdr)) {
- GC_printf1("Missing header!!\n", hhdr);
+ GC_printf1("Missing header!!(%ld)\n", hhdr);
p += HBLKSIZE;
continue;
}
hdr * hhdr;
int n;
{
+ int index;
+
GC_ASSERT(((hhdr -> hb_sz) & (HBLKSIZE-1)) == 0);
+# ifndef USE_MUNMAP
+ /* We always need index to mainatin free counts. */
+ if (FL_UNKNOWN == n) {
+ index = GC_hblk_fl_from_blocks(divHBLKSZ(hhdr -> hb_sz));
+ } else {
+ index = n;
+ }
+# endif
if (hhdr -> hb_prev == 0) {
- int index;
- if (FL_UNKNOWN == n) {
+# ifdef USE_MUNMAP
+ if (FL_UNKNOWN == n) {
index = GC_hblk_fl_from_blocks(divHBLKSZ(hhdr -> hb_sz));
- } else {
+ } else {
index = n;
- }
+ }
+# endif
GC_ASSERT(HDR(GC_hblkfreelist[index]) == hhdr);
GC_hblkfreelist[index] = hhdr -> hb_next;
} else {
- PHDR(hhdr) -> hb_next = hhdr -> hb_next;
+ hdr *phdr;
+ GET_HDR(hhdr -> hb_prev, phdr);
+ phdr -> hb_next = hhdr -> hb_next;
}
+ FREE_ASSERT(GC_free_bytes[index] >= hhdr -> hb_sz);
+ INCR_FREE_BYTES(index, - (signed_word)(hhdr -> hb_sz));
if (0 != hhdr -> hb_next) {
+ hdr * nhdr;
GC_ASSERT(!IS_FORWARDING_ADDR_OR_NIL(NHDR(hhdr)));
- NHDR(hhdr) -> hb_prev = hhdr -> hb_prev;
+ GET_HDR(hhdr -> hb_next, nhdr);
+ nhdr -> hb_prev = hhdr -> hb_prev;
}
}
struct hblk *h;
{
struct hblk * p = h - 1;
- hdr * phdr = HDR(p);
+ hdr * phdr;
+ GET_HDR(p, phdr);
while (0 != phdr && IS_FORWARDING_ADDR_OR_NIL(phdr)) {
p = FORWARDED_ADDR(p,phdr);
phdr = HDR(p);
}
- if (0 != phdr && HBLK_IS_FREE(phdr)) return p;
+ if (0 != phdr) {
+ if(HBLK_IS_FREE(phdr)) {
+ return p;
+ } else {
+ return 0;
+ }
+ }
p = GC_prev_block(h - 1);
if (0 != p) {
phdr = HDR(p);
{
int index = GC_hblk_fl_from_blocks(divHBLKSZ(hhdr -> hb_sz));
struct hblk *second = GC_hblkfreelist[index];
+ hdr * second_hdr;
# ifdef GC_ASSERTIONS
struct hblk *next = (struct hblk *)((word)h + hhdr -> hb_sz);
hdr * nexthdr = HDR(next);
# endif
GC_ASSERT(((hhdr -> hb_sz) & (HBLKSIZE-1)) == 0);
GC_hblkfreelist[index] = h;
+ INCR_FREE_BYTES(index, hhdr -> hb_sz);
+ FREE_ASSERT(GC_free_bytes[index] <= GC_large_free_bytes)
hhdr -> hb_next = second;
hhdr -> hb_prev = 0;
- if (0 != second) HDR(second) -> hb_prev = h;
+ if (0 != second) {
+ GET_HDR(second, second_hdr);
+ second_hdr -> hb_prev = h;
+ }
GC_invalidate_map(hhdr);
}
if (!IS_MAPPED(hhdr)) continue;
threshold = (unsigned short)(GC_gc_no - UNMAP_THRESHOLD);
last_rec = hhdr -> hb_last_reclaimed;
- if (last_rec > GC_gc_no
- || last_rec < threshold && threshold < GC_gc_no
- /* not recently wrapped */) {
+ if ((last_rec > GC_gc_no || last_rec < threshold)
+ && threshold < GC_gc_no /* not recently wrapped */) {
sz = hhdr -> hb_sz;
GC_unmap((ptr_t)h, sz);
hhdr -> hb_flags |= WAS_UNMAPPED;
for (i = 0; i <= N_HBLK_FLS; ++i) {
h = GC_hblkfreelist[i];
while (h != 0) {
- hhdr = HDR(h);
+ GET_HDR(h, hhdr);
size = hhdr->hb_sz;
next = (struct hblk *)((word)h + size);
- nexthdr = HDR(next);
+ GET_HDR(next, nexthdr);
/* Coalesce with successor, if possible */
if (0 != nexthdr && HBLK_IS_FREE(nexthdr)) {
nextsize = nexthdr -> hb_sz;
} else {
GC_remap((ptr_t)h, size);
hhdr -> hb_flags &= ~WAS_UNMAPPED;
+ hhdr -> hb_last_reclaimed = nexthdr -> hb_last_reclaimed;
}
} else {
/* Unmap any gap in the middle */
GC_remove_from_fl(hhdr, index);
if (total_size == bytes) return h;
rest = (struct hblk *)((word)h + bytes);
- if (!GC_install_header(rest)) return(0);
- rest_hdr = HDR(rest);
+ rest_hdr = GC_install_header(rest);
+ if (0 == rest_hdr) {
+ /* This may be very bad news ... */
+ WARN("Header allocation failed: Dropping block.\n", 0);
+ return(0);
+ }
rest_hdr -> hb_sz = total_size - bytes;
rest_hdr -> hb_flags = 0;
# ifdef GC_ASSERTIONS
- // Mark h not free, to avoid assertion about adjacent free blocks.
+ /* Mark h not free, to avoid assertion about adjacent free blocks. */
hhdr -> hb_map = 0;
# endif
GC_add_to_fl(rest, rest_hdr);
if (0 != next) {
HDR(next) -> hb_prev = n;
}
+ INCR_FREE_BYTES(index, -(signed_word)h_size);
+ FREE_ASSERT(GC_free_bytes[index] > 0);
# ifdef GC_ASSERTIONS
nhdr -> hb_map = 0; /* Don't fail test for consecutive */
/* free blocks in GC_add_to_fl. */
* NOTE: We set obj_map field in header correctly.
* Caller is responsible for building an object freelist in block.
*
- * We clear the block if it is destined for large objects, and if
- * kind requires that newly allocated objects be cleared.
+ * Unlike older versions of the collectors, the client is responsible
+ * for clearing the block, if necessary.
*/
struct hblk *
GC_allochblk(sz, kind, flags)
word sz;
int kind;
-unsigned char flags; /* IGNORE_OFF_PAGE or 0 */
+unsigned flags; /* IGNORE_OFF_PAGE or 0 */
{
- int start_list = GC_hblk_fl_from_blocks(OBJ_SZ_TO_BLOCKS(sz));
+ word blocks = OBJ_SZ_TO_BLOCKS(sz);
+ int start_list = GC_hblk_fl_from_blocks(blocks);
int i;
for (i = start_list; i <= N_HBLK_FLS; ++i) {
struct hblk * result = GC_allochblk_nth(sz, kind, flags, i);
- if (0 != result) return result;
+ if (0 != result) {
+ return result;
+ }
}
return 0;
}
/* search for a big enough block in free list */
hbp = GC_hblkfreelist[n];
- hhdr = HDR(hbp);
- for(; 0 != hbp; hbp = hhdr -> hb_next, hhdr = HDR(hbp)) {
+ for(; 0 != hbp; hbp = hhdr -> hb_next) {
+ GET_HDR(hbp, hhdr);
size_avail = hhdr->hb_sz;
if (size_avail < size_needed) continue;
-# ifdef PRESERVE_LAST
- if (size_avail != size_needed
- && !GC_incremental && GC_should_collect()) {
+ if (size_avail != size_needed
+ && !GC_use_entire_heap
+ && !GC_dont_gc
+ && USED_HEAP_SIZE >= GC_requested_heapsize
+ && !TRUE_INCREMENTAL && GC_should_collect()) {
+# ifdef USE_MUNMAP
continue;
- }
-# endif
+# else
+ /* If we have enough large blocks left to cover any */
+ /* previous request for large blocks, we go ahead */
+ /* and split. Assuming a steady state, that should */
+ /* be safe. It means that we can use the full */
+ /* heap if we allocate only small objects. */
+ if (!GC_enough_large_bytes_left(GC_large_allocd_bytes, n)) {
+ continue;
+ }
+ /* If we are deallocating lots of memory from */
+ /* finalizers, fail and collect sooner rather */
+ /* than later. */
+ if (WORDS_TO_BYTES(GC_finalizer_mem_freed)
+ > (GC_heapsize >> 4)) {
+ continue;
+ }
+# endif /* !USE_MUNMAP */
+ }
/* If the next heap block is obviously better, go on. */
/* This prevents us from disassembling a single large block */
/* to get tiny blocks. */
thishbp = hhdr -> hb_next;
if (thishbp != 0) {
- thishdr = HDR(thishbp);
+ GET_HDR(thishbp, thishdr);
next_size = (signed_word)(thishdr -> hb_sz);
if (next_size < size_avail
&& next_size >= size_needed
while ((ptr_t)lasthbp <= search_end
&& (thishbp = GC_is_black_listed(lasthbp,
- (word)eff_size_needed))) {
+ (word)eff_size_needed))
+ != 0) {
lasthbp = thishbp;
}
size_avail -= (ptr_t)lasthbp - (ptr_t)hbp;
thishbp = lasthbp;
if (size_avail >= size_needed) {
- if (thishbp != hbp && GC_install_header(thishbp)) {
+ if (thishbp != hbp &&
+ 0 != (thishdr = GC_install_header(thishbp))) {
/* Make sure it's mapped before we mangle it. */
# ifdef USE_MUNMAP
if (!IS_MAPPED(hhdr)) {
- GC_remap((ptr_t)hbp, size_avail);
+ GC_remap((ptr_t)hbp, hhdr -> hb_sz);
hhdr -> hb_flags &= ~WAS_UNMAPPED;
}
# endif
/* Split the block at thishbp */
- thishdr = HDR(thishbp);
GC_split_block(hbp, hhdr, thishbp, thishdr, n);
/* Advance to thishbp */
hbp = thishbp;
&& orig_avail - size_needed
> (signed_word)BL_LIMIT) {
/* Punt, since anything else risks unreasonable heap growth. */
- WARN("Needed to allocate blacklisted block at 0x%lx\n",
- (word)hbp);
+ if (++GC_large_alloc_warn_suppressed
+ >= GC_large_alloc_warn_interval) {
+ WARN("Repeated allocation of very large block "
+ "(appr. size %ld):\n"
+ "\tMay lead to memory leak and poor performance.\n",
+ size_needed);
+ GC_large_alloc_warn_suppressed = 0;
+ }
size_avail = orig_avail;
} else if (size_avail == 0 && size_needed == HBLKSIZE
&& IS_MAPPED(hhdr)) {
struct hblk * h;
struct hblk * prev = hhdr -> hb_prev;
- GC_words_wasted += total_size;
+ GC_words_wasted += BYTES_TO_WORDS(total_size);
GC_large_free_bytes -= total_size;
GC_remove_from_fl(hhdr, n);
for (h = hbp; h < limit; h++) {
- if (h == hbp || GC_install_header(h)) {
- hhdr = HDR(h);
+ if (h == hbp || 0 != (hhdr = GC_install_header(h))) {
(void) setup_header(
hhdr,
- BYTES_TO_WORDS(HBLKSIZE - HDR_BYTES),
+ BYTES_TO_WORDS(HBLKSIZE),
PTRFREE, 0); /* Cant fail */
if (GC_debugging_started) {
- BZERO(h + HDR_BYTES, HBLKSIZE - HDR_BYTES);
+ BZERO(h, HBLKSIZE);
}
}
}
if( size_avail >= size_needed ) {
# ifdef USE_MUNMAP
if (!IS_MAPPED(hhdr)) {
- GC_remap((ptr_t)hbp, size_avail);
+ GC_remap((ptr_t)hbp, hhdr -> hb_sz);
hhdr -> hb_flags &= ~WAS_UNMAPPED;
}
# endif
if (0 == hbp) return 0;
- /* Notify virtual dirty bit implementation that we are about to write. */
- GC_write_hint(hbp);
-
/* Add it to map of valid blocks */
if (!GC_install_counts(hbp, (word)size_needed)) return(0);
/* This leaks memory under very rare conditions. */
GC_remove_counts(hbp, (word)size_needed);
return(0); /* ditto */
}
-
- /* Clear block if necessary */
- if (GC_debugging_started
- || sz > MAXOBJSZ && GC_obj_kinds[kind].ok_init) {
- BZERO(hbp + HDR_BYTES, size_needed - HDR_BYTES);
- }
+ /* Notify virtual dirty bit implementation that we are about to write. */
+ /* Ensure that pointerfree objects are not protected if it's avoidable. */
+ GC_remove_protection(hbp, divHBLKSZ(size_needed),
+ (hhdr -> hb_descr == 0) /* pointer-free */);
+
/* We just successfully allocated a block. Restart count of */
/* consecutive failures. */
{
signed_word size;
- hhdr = HDR(hbp);
+ GET_HDR(hbp, hhdr);
size = hhdr->hb_sz;
size = HBLKSIZE * OBJ_SZ_TO_BLOCKS(size);
GC_remove_counts(hbp, (word)size);
hhdr->hb_sz = size;
+# ifdef USE_MUNMAP
+ hhdr -> hb_last_reclaimed = GC_gc_no;
+# endif
/* Check for duplicate deallocation in the easy case */
if (HBLK_IS_FREE(hhdr)) {
GC_printf1("Duplicate large block deallocation of 0x%lx\n",
(unsigned long) hbp);
+ ABORT("Duplicate large block deallocation");
}
GC_ASSERT(IS_MAPPED(hhdr));
GC_invalidate_map(hhdr);
next = (struct hblk *)((word)hbp + size);
- nexthdr = HDR(next);
+ GET_HDR(next, nexthdr);
prev = GC_free_block_ending_at(hbp);
/* Coalesce with successor, if possible */
if(0 != nexthdr && HBLK_IS_FREE(nexthdr) && IS_MAPPED(nexthdr)) {
if (IS_MAPPED(prevhdr)) {
GC_remove_from_fl(prevhdr, FL_UNKNOWN);
prevhdr -> hb_sz += hhdr -> hb_sz;
+# ifdef USE_MUNMAP
+ prevhdr -> hb_last_reclaimed = GC_gc_no;
+# endif
GC_remove_header(hbp);
hbp = prev;
hhdr = prevhdr;
}
}
+ /* FIXME: It is not clear we really always want to do these merges */
+ /* with -DUSE_MUNMAP, since it updates ages and hence prevents */
+ /* unmapping. */
GC_large_free_bytes += size;
GC_add_to_fl(hbp, hhdr);