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-rw-r--r--mallocx.c401
1 files changed, 327 insertions, 74 deletions
diff --git a/mallocx.c b/mallocx.c
index c842665..031fcaf 100644
--- a/mallocx.c
+++ b/mallocx.c
@@ -2,6 +2,7 @@
* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
* Copyright (c) 1996 by Silicon Graphics. All rights reserved.
+ * Copyright (c) 2000 by Hewlett-Packard Company. All rights reserved.
*
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
@@ -21,7 +22,7 @@
*/
#include <stdio.h>
-#include "gc_priv.h"
+#include "private/gc_priv.h"
extern ptr_t GC_clear_stack(); /* in misc.c, behaves like identity */
void GC_extend_size_map(); /* in misc.c. */
@@ -30,69 +31,179 @@ GC_bool GC_alloc_reclaim_list(); /* in malloc.c */
/* Some externally visible but unadvertised variables to allow access to */
/* free lists from inlined allocators without including gc_priv.h */
/* or introducing dependencies on internal data structure layouts. */
-ptr_t * CONST GC_objfreelist_ptr = GC_objfreelist;
-ptr_t * CONST GC_aobjfreelist_ptr = GC_aobjfreelist;
-ptr_t * CONST GC_uobjfreelist_ptr = GC_uobjfreelist;
+ptr_t * GC_CONST GC_objfreelist_ptr = GC_objfreelist;
+ptr_t * GC_CONST GC_aobjfreelist_ptr = GC_aobjfreelist;
+ptr_t * GC_CONST GC_uobjfreelist_ptr = GC_uobjfreelist;
# ifdef ATOMIC_UNCOLLECTABLE
- ptr_t * CONST GC_auobjfreelist_ptr = GC_auobjfreelist;
+ ptr_t * GC_CONST GC_auobjfreelist_ptr = GC_auobjfreelist;
# endif
-/* Allocate a composite object of size n bytes. The caller guarantees */
-/* that pointers past the first page are not relevant. Caller holds */
-/* allocation lock. */
-ptr_t GC_generic_malloc_inner_ignore_off_page(lb, k)
-register size_t lb;
-register int k;
+
+GC_PTR GC_generic_or_special_malloc(lb,knd)
+word lb;
+int knd;
{
- register struct hblk * h;
- register word n_blocks;
- register word lw;
- register ptr_t op;
-
- if (lb <= HBLKSIZE)
- return(GC_generic_malloc_inner((word)lb, k));
- n_blocks = divHBLKSZ(ADD_SLOP(lb) + HDR_BYTES + HBLKSIZE-1);
- if (!GC_is_initialized) GC_init_inner();
- /* Do our share of marking work */
- if(GC_incremental && !GC_dont_gc)
- GC_collect_a_little_inner((int)n_blocks);
- lw = ROUNDED_UP_WORDS(lb);
- h = GC_allochblk(lw, k, IGNORE_OFF_PAGE);
-# ifdef USE_MUNMAP
- if (0 == h) {
- GC_merge_unmapped();
- h = GC_allochblk(lw, k, IGNORE_OFF_PAGE);
- }
-# endif
- while (0 == h && GC_collect_or_expand(n_blocks, TRUE)) {
- h = GC_allochblk(lw, k, IGNORE_OFF_PAGE);
+ switch(knd) {
+# ifdef STUBBORN_ALLOC
+ case STUBBORN:
+ return(GC_malloc_stubborn((size_t)lb));
+# endif
+ case PTRFREE:
+ return(GC_malloc_atomic((size_t)lb));
+ case NORMAL:
+ return(GC_malloc((size_t)lb));
+ case UNCOLLECTABLE:
+ return(GC_malloc_uncollectable((size_t)lb));
+# ifdef ATOMIC_UNCOLLECTABLE
+ case AUNCOLLECTABLE:
+ return(GC_malloc_atomic_uncollectable((size_t)lb));
+# endif /* ATOMIC_UNCOLLECTABLE */
+ default:
+ return(GC_generic_malloc(lb,knd));
+ }
+}
+
+
+/* Change the size of the block pointed to by p to contain at least */
+/* lb bytes. The object may be (and quite likely will be) moved. */
+/* The kind (e.g. atomic) is the same as that of the old. */
+/* Shrinking of large blocks is not implemented well. */
+# ifdef __STDC__
+ GC_PTR GC_realloc(GC_PTR p, size_t lb)
+# else
+ GC_PTR GC_realloc(p,lb)
+ GC_PTR p;
+ size_t lb;
+# endif
+{
+register struct hblk * h;
+register hdr * hhdr;
+register word sz; /* Current size in bytes */
+register word orig_sz; /* Original sz in bytes */
+int obj_kind;
+
+ if (p == 0) return(GC_malloc(lb)); /* Required by ANSI */
+ h = HBLKPTR(p);
+ hhdr = HDR(h);
+ sz = hhdr -> hb_sz;
+ obj_kind = hhdr -> hb_obj_kind;
+ sz = WORDS_TO_BYTES(sz);
+ orig_sz = sz;
+
+ if (sz > MAXOBJBYTES) {
+ /* Round it up to the next whole heap block */
+ register word descr;
+
+ sz = (sz+HBLKSIZE-1) & (~HBLKMASK);
+ hhdr -> hb_sz = BYTES_TO_WORDS(sz);
+ descr = GC_obj_kinds[obj_kind].ok_descriptor;
+ if (GC_obj_kinds[obj_kind].ok_relocate_descr) descr += sz;
+ hhdr -> hb_descr = descr;
+ if (IS_UNCOLLECTABLE(obj_kind)) GC_non_gc_bytes += (sz - orig_sz);
+ /* Extra area is already cleared by GC_alloc_large_and_clear. */
}
- if (h == 0) {
- op = 0;
+ if (ADD_SLOP(lb) <= sz) {
+ if (lb >= (sz >> 1)) {
+# ifdef STUBBORN_ALLOC
+ if (obj_kind == STUBBORN) GC_change_stubborn(p);
+# endif
+ if (orig_sz > lb) {
+ /* Clear unneeded part of object to avoid bogus pointer */
+ /* tracing. */
+ /* Safe for stubborn objects. */
+ BZERO(((ptr_t)p) + lb, orig_sz - lb);
+ }
+ return(p);
+ } else {
+ /* shrink */
+ GC_PTR result =
+ GC_generic_or_special_malloc((word)lb, obj_kind);
+
+ if (result == 0) return(0);
+ /* Could also return original object. But this */
+ /* gives the client warning of imminent disaster. */
+ BCOPY(p, result, lb);
+# ifndef IGNORE_FREE
+ GC_free(p);
+# endif
+ return(result);
+ }
} else {
- op = (ptr_t) (h -> hb_body);
- GC_words_wasted += BYTES_TO_WORDS(n_blocks * HBLKSIZE) - lw;
+ /* grow */
+ GC_PTR result =
+ GC_generic_or_special_malloc((word)lb, obj_kind);
+
+ if (result == 0) return(0);
+ BCOPY(p, result, sz);
+# ifndef IGNORE_FREE
+ GC_free(p);
+# endif
+ return(result);
}
- GC_words_allocd += lw;
- return((ptr_t)op);
}
+# if defined(REDIRECT_MALLOC) || defined(REDIRECT_REALLOC)
+# ifdef __STDC__
+ GC_PTR realloc(GC_PTR p, size_t lb)
+# else
+ GC_PTR realloc(p,lb)
+ GC_PTR p;
+ size_t lb;
+# endif
+ {
+# ifdef REDIRECT_REALLOC
+ return(REDIRECT_REALLOC(p, lb));
+# else
+ return(GC_realloc(p, lb));
+# endif
+ }
+# endif /* REDIRECT_MALLOC */
+
+
+/* The same thing, except caller does not hold allocation lock. */
+/* We avoid holding allocation lock while we clear memory. */
ptr_t GC_generic_malloc_ignore_off_page(lb, k)
register size_t lb;
register int k;
{
register ptr_t result;
+ word lw;
+ word n_blocks;
+ GC_bool init;
DCL_LOCK_STATE;
+ if (SMALL_OBJ(lb))
+ return(GC_generic_malloc((word)lb, k));
+ lw = ROUNDED_UP_WORDS(lb);
+ n_blocks = OBJ_SZ_TO_BLOCKS(lw);
+ init = GC_obj_kinds[k].ok_init;
GC_INVOKE_FINALIZERS();
DISABLE_SIGNALS();
LOCK();
- result = GC_generic_malloc_inner_ignore_off_page(lb,k);
+ result = (ptr_t)GC_alloc_large(lw, k, IGNORE_OFF_PAGE);
+ if (0 != result) {
+ if (GC_debugging_started) {
+ BZERO(result, n_blocks * HBLKSIZE);
+ } else {
+# ifdef THREADS
+ /* Clear any memory that might be used for GC descriptors */
+ /* before we release the lock. */
+ ((word *)result)[0] = 0;
+ ((word *)result)[1] = 0;
+ ((word *)result)[lw-1] = 0;
+ ((word *)result)[lw-2] = 0;
+# endif
+ }
+ }
+ GC_words_allocd += lw;
UNLOCK();
ENABLE_SIGNALS();
if (0 == result) {
return((*GC_oom_fn)(lb));
} else {
+ if (init & !GC_debugging_started) {
+ BZERO(result, n_blocks * HBLKSIZE);
+ }
return(result);
}
}
@@ -185,6 +296,24 @@ DCL_LOCK_STATE;
}
#if defined(THREADS) && !defined(SRC_M3)
+
+extern signed_word GC_mem_found; /* Protected by GC lock. */
+
+#ifdef PARALLEL_MARK
+volatile signed_word GC_words_allocd_tmp = 0;
+ /* Number of words of memory allocated since */
+ /* we released the GC lock. Instead of */
+ /* reacquiring the GC lock just to add this in, */
+ /* we add it in the next time we reacquire */
+ /* the lock. (Atomically adding it doesn't */
+ /* work, since we would have to atomically */
+ /* update it in GC_malloc, which is too */
+ /* expensive. */
+#endif /* PARALLEL_MARK */
+
+/* See reclaim.c: */
+extern ptr_t GC_reclaim_generic();
+
/* Return a list of 1 or more objects of the indicated size, linked */
/* through the first word in the object. This has the advantage that */
/* it acquires the allocation lock only once, and may greatly reduce */
@@ -194,63 +323,191 @@ DCL_LOCK_STATE;
/* GC_malloc_many or friends to replenish it. (We do not round up */
/* object sizes, since a call indicates the intention to consume many */
/* objects of exactly this size.) */
+/* We return the free-list by assigning it to *result, since it is */
+/* not safe to return, e.g. a linked list of pointer-free objects, */
+/* since the collector would not retain the entire list if it were */
+/* invoked just as we were returning. */
/* Note that the client should usually clear the link field. */
-ptr_t GC_generic_malloc_many(lb, k)
+void GC_generic_malloc_many(lb, k, result)
register word lb;
register int k;
+ptr_t *result;
{
ptr_t op;
-register ptr_t p;
+ptr_t p;
ptr_t *opp;
word lw;
-register word my_words_allocd;
+word my_words_allocd = 0;
+struct obj_kind * ok = &(GC_obj_kinds[k]);
DCL_LOCK_STATE;
+# if defined(GATHERSTATS) || defined(PARALLEL_MARK)
+# define COUNT_ARG , &my_words_allocd
+# else
+# define COUNT_ARG
+# define NEED_TO_COUNT
+# endif
if (!SMALL_OBJ(lb)) {
op = GC_generic_malloc(lb, k);
if(0 != op) obj_link(op) = 0;
- return(op);
+ *result = op;
+ return;
}
lw = ALIGNED_WORDS(lb);
GC_INVOKE_FINALIZERS();
DISABLE_SIGNALS();
LOCK();
- opp = &(GC_obj_kinds[k].ok_freelist[lw]);
- if( (op = *opp) == 0 ) {
- if (!GC_is_initialized) {
- GC_init_inner();
- }
- op = GC_clear_stack(GC_allocobj(lw, k));
- if (op == 0) {
- UNLOCK();
- ENABLE_SIGNALS();
- op = (*GC_oom_fn)(lb);
- if(0 != op) obj_link(op) = 0;
- return(op);
- }
+ if (!GC_is_initialized) GC_init_inner();
+ /* Do our share of marking work */
+ if (GC_incremental && !GC_dont_gc) {
+ ENTER_GC();
+ GC_collect_a_little_inner(1);
+ EXIT_GC();
+ }
+ /* First see if we can reclaim a page of objects waiting to be */
+ /* reclaimed. */
+ {
+ struct hblk ** rlh = ok -> ok_reclaim_list;
+ struct hblk * hbp;
+ hdr * hhdr;
+
+ rlh += lw;
+ while ((hbp = *rlh) != 0) {
+ hhdr = HDR(hbp);
+ *rlh = hhdr -> hb_next;
+# ifdef PARALLEL_MARK
+ {
+ signed_word my_words_allocd_tmp = GC_words_allocd_tmp;
+
+ GC_ASSERT(my_words_allocd_tmp >= 0);
+ /* We only decrement it while holding the GC lock. */
+ /* Thus we can't accidentally adjust it down in more */
+ /* than one thread simultaneously. */
+ if (my_words_allocd_tmp != 0) {
+ (void)GC_atomic_add(
+ (volatile GC_word *)(&GC_words_allocd_tmp),
+ (GC_word)(-my_words_allocd_tmp));
+ GC_words_allocd += my_words_allocd_tmp;
+ }
+ }
+ GC_acquire_mark_lock();
+ ++ GC_fl_builder_count;
+ UNLOCK();
+ ENABLE_SIGNALS();
+ GC_release_mark_lock();
+# endif
+ op = GC_reclaim_generic(hbp, hhdr, lw,
+ ok -> ok_init, 0 COUNT_ARG);
+ if (op != 0) {
+# ifdef NEED_TO_COUNT
+ /* We are neither gathering statistics, nor marking in */
+ /* parallel. Thus GC_reclaim_generic doesn't count */
+ /* for us. */
+ for (p = op; p != 0; p = obj_link(p)) {
+ my_words_allocd += lw;
+ }
+# endif
+# if defined(GATHERSTATS)
+ /* We also reclaimed memory, so we need to adjust */
+ /* that count. */
+ /* This should be atomic, so the results may be */
+ /* inaccurate. */
+ GC_mem_found += my_words_allocd;
+# endif
+# ifdef PARALLEL_MARK
+ *result = op;
+ (void)GC_atomic_add(
+ (volatile GC_word *)(&GC_words_allocd_tmp),
+ (GC_word)(my_words_allocd));
+ GC_acquire_mark_lock();
+ -- GC_fl_builder_count;
+ if (GC_fl_builder_count == 0) GC_notify_all_builder();
+ GC_release_mark_lock();
+ (void) GC_clear_stack(0);
+ return;
+# else
+ GC_words_allocd += my_words_allocd;
+ goto out;
+# endif
+ }
+# ifdef PARALLEL_MARK
+ GC_acquire_mark_lock();
+ -- GC_fl_builder_count;
+ if (GC_fl_builder_count == 0) GC_notify_all_builder();
+ GC_release_mark_lock();
+ DISABLE_SIGNALS();
+ LOCK();
+ /* GC lock is needed for reclaim list access. We */
+ /* must decrement fl_builder_count before reaquiring GC */
+ /* lock. Hopefully this path is rare. */
+# endif
+ }
}
- *opp = 0;
- my_words_allocd = 0;
- for (p = op; p != 0; p = obj_link(p)) {
- my_words_allocd += lw;
- if (my_words_allocd >= BODY_SZ) {
+ /* Next try to use prefix of global free list if there is one. */
+ /* We don't refill it, but we need to use it up before allocating */
+ /* a new block ourselves. */
+ opp = &(GC_obj_kinds[k].ok_freelist[lw]);
+ if ( (op = *opp) != 0 ) {
+ *opp = 0;
+ my_words_allocd = 0;
+ for (p = op; p != 0; p = obj_link(p)) {
+ my_words_allocd += lw;
+ if (my_words_allocd >= BODY_SZ) {
*opp = obj_link(p);
obj_link(p) = 0;
break;
+ }
}
+ GC_words_allocd += my_words_allocd;
+ goto out;
+ }
+ /* Next try to allocate a new block worth of objects of this size. */
+ {
+ struct hblk *h = GC_allochblk(lw, k, 0);
+ if (h != 0) {
+ if (IS_UNCOLLECTABLE(k)) GC_set_hdr_marks(HDR(h));
+ GC_words_allocd += BYTES_TO_WORDS(HBLKSIZE)
+ - BYTES_TO_WORDS(HBLKSIZE) % lw;
+# ifdef PARALLEL_MARK
+ GC_acquire_mark_lock();
+ ++ GC_fl_builder_count;
+ UNLOCK();
+ ENABLE_SIGNALS();
+ GC_release_mark_lock();
+# endif
+
+ op = GC_build_fl(h, lw, ok -> ok_init, 0);
+# ifdef PARALLEL_MARK
+ *result = op;
+ GC_acquire_mark_lock();
+ -- GC_fl_builder_count;
+ if (GC_fl_builder_count == 0) GC_notify_all_builder();
+ GC_release_mark_lock();
+ (void) GC_clear_stack(0);
+ return;
+# else
+ goto out;
+# endif
+ }
}
- GC_words_allocd += my_words_allocd;
-out:
+ /* As a last attempt, try allocating a single object. Note that */
+ /* this may trigger a collection or expand the heap. */
+ op = GC_generic_malloc_inner(lb, k);
+ if (0 != op) obj_link(op) = 0;
+
+ out:
+ *result = op;
UNLOCK();
ENABLE_SIGNALS();
- return(op);
-
+ (void) GC_clear_stack(0);
}
-void * GC_malloc_many(size_t lb)
+GC_PTR GC_malloc_many(size_t lb)
{
- return(GC_generic_malloc_many(lb, NORMAL));
+ ptr_t result;
+ GC_generic_malloc_many(lb, NORMAL, &result);
+ return result;
}
/* Note that the "atomic" version of this would be unsafe, since the */
@@ -272,11 +529,9 @@ DCL_LOCK_STATE;
if( SMALL_OBJ(lb) ) {
# ifdef MERGE_SIZES
-# ifdef ADD_BYTE_AT_END
- if (lb != 0) lb--;
+ if (EXTRA_BYTES != 0 && lb != 0) lb--;
/* We don't need the extra byte, since this won't be */
/* collected anyway. */
-# endif
lw = GC_size_map[lb];
# else
lw = ALIGNED_WORDS(lb);
@@ -338,11 +593,9 @@ DCL_LOCK_STATE;
if( SMALL_OBJ(lb) ) {
# ifdef MERGE_SIZES
-# ifdef ADD_BYTE_AT_END
- if (lb != 0) lb--;
+ if (EXTRA_BYTES != 0 && lb != 0) lb--;
/* We don't need the extra byte, since this won't be */
/* collected anyway. */
-# endif
lw = GC_size_map[lb];
# else
lw = ALIGNED_WORDS(lb);