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903 lines
26 KiB
C
903 lines
26 KiB
C
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/*
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* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
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* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
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* Copyright (c) 1998 by Silicon Graphics. All rights reserved.
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*
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* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
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* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
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*
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* Permission is hereby granted to use or copy this program
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* for any purpose, provided the above notices are retained on all copies.
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* Permission to modify the code and to distribute modified code is granted,
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* provided the above notices are retained, and a notice that the code was
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* modified is included with the above copyright notice.
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*
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*/
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# include "gc_priv.h"
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# include <stdio.h>
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# ifndef MACOS
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# include <signal.h>
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# include <sys/types.h>
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# endif
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/*
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* Separate free lists are maintained for different sized objects
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* up to MAXOBJSZ.
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* The call GC_allocobj(i,k) ensures that the freelist for
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* kind k objects of size i points to a non-empty
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* free list. It returns a pointer to the first entry on the free list.
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* In a single-threaded world, GC_allocobj may be called to allocate
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* an object of (small) size i as follows:
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*
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* opp = &(GC_objfreelist[i]);
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* if (*opp == 0) GC_allocobj(i, NORMAL);
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* ptr = *opp;
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* *opp = obj_link(ptr);
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*
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* Note that this is very fast if the free list is non-empty; it should
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* only involve the execution of 4 or 5 simple instructions.
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* All composite objects on freelists are cleared, except for
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* their first word.
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*/
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/*
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* The allocator uses GC_allochblk to allocate large chunks of objects.
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* These chunks all start on addresses which are multiples of
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* HBLKSZ. Each allocated chunk has an associated header,
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* which can be located quickly based on the address of the chunk.
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* (See headers.c for details.)
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* This makes it possible to check quickly whether an
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* arbitrary address corresponds to an object administered by the
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* allocator.
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*/
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word GC_non_gc_bytes = 0; /* Number of bytes not intended to be collected */
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word GC_gc_no = 0;
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#ifndef SMALL_CONFIG
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int GC_incremental = 0; /* By default, stop the world. */
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#endif
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int GC_full_freq = 4; /* Every 5th collection is a full */
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/* collection. */
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char * GC_copyright[] =
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{"Copyright 1988,1989 Hans-J. Boehm and Alan J. Demers ",
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"Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved. ",
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"Copyright (c) 1996-1998 by Silicon Graphics. All rights reserved. ",
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"THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY",
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" EXPRESSED OR IMPLIED. ANY USE IS AT YOUR OWN RISK.",
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"See source code for details." };
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# include "version.h"
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/* some more variables */
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extern signed_word GC_mem_found; /* Number of reclaimed longwords */
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/* after garbage collection */
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GC_bool GC_dont_expand = 0;
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word GC_free_space_divisor = 4;
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extern GC_bool GC_collection_in_progress();
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/* Collection is in progress, or was abandoned. */
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int GC_never_stop_func GC_PROTO((void)) { return(0); }
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CLOCK_TYPE GC_start_time; /* Time at which we stopped world. */
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/* used only in GC_timeout_stop_func. */
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int GC_n_attempts = 0; /* Number of attempts at finishing */
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/* collection within TIME_LIMIT */
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#ifdef SMALL_CONFIG
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# define GC_timeout_stop_func GC_never_stop_func
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#else
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int GC_timeout_stop_func GC_PROTO((void))
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{
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CLOCK_TYPE current_time;
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static unsigned count = 0;
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unsigned long time_diff;
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if ((count++ & 3) != 0) return(0);
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GET_TIME(current_time);
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time_diff = MS_TIME_DIFF(current_time,GC_start_time);
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if (time_diff >= TIME_LIMIT) {
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# ifdef PRINTSTATS
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GC_printf0("Abandoning stopped marking after ");
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GC_printf1("%lu msecs", (unsigned long)time_diff);
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GC_printf1("(attempt %d)\n", (unsigned long) GC_n_attempts);
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# endif
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return(1);
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}
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return(0);
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}
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#endif /* !SMALL_CONFIG */
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/* Return the minimum number of words that must be allocated between */
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/* collections to amortize the collection cost. */
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static word min_words_allocd()
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{
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# ifdef THREADS
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/* We punt, for now. */
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register signed_word stack_size = 10000;
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# else
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int dummy;
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register signed_word stack_size = (ptr_t)(&dummy) - GC_stackbottom;
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# endif
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register word total_root_size; /* includes double stack size, */
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/* since the stack is expensive */
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/* to scan. */
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if (stack_size < 0) stack_size = -stack_size;
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total_root_size = 2 * stack_size + GC_root_size;
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if (GC_incremental) {
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return(BYTES_TO_WORDS(GC_heapsize + total_root_size)
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/ (2 * GC_free_space_divisor));
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} else {
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return(BYTES_TO_WORDS(GC_heapsize + total_root_size)
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/ GC_free_space_divisor);
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}
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}
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/* Return the number of words allocated, adjusted for explicit storage */
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/* management, etc.. This number is used in deciding when to trigger */
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/* collections. */
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word GC_adj_words_allocd()
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{
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register signed_word result;
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register signed_word expl_managed =
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BYTES_TO_WORDS((long)GC_non_gc_bytes
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- (long)GC_non_gc_bytes_at_gc);
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/* Don't count what was explicitly freed, or newly allocated for */
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/* explicit management. Note that deallocating an explicitly */
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/* managed object should not alter result, assuming the client */
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/* is playing by the rules. */
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result = (signed_word)GC_words_allocd
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- (signed_word)GC_mem_freed - expl_managed;
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if (result > (signed_word)GC_words_allocd) {
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result = GC_words_allocd;
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/* probably client bug or unfortunate scheduling */
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}
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result += GC_words_finalized;
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/* We count objects enqueued for finalization as though they */
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/* had been reallocated this round. Finalization is user */
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/* visible progress. And if we don't count this, we have */
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/* stability problems for programs that finalize all objects. */
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result += GC_words_wasted;
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/* This doesn't reflect useful work. But if there is lots of */
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/* new fragmentation, the same is probably true of the heap, */
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/* and the collection will be correspondingly cheaper. */
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if (result < (signed_word)(GC_words_allocd >> 3)) {
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/* Always count at least 1/8 of the allocations. We don't want */
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/* to collect too infrequently, since that would inhibit */
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/* coalescing of free storage blocks. */
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/* This also makes us partially robust against client bugs. */
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return(GC_words_allocd >> 3);
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} else {
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return(result);
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}
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}
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/* Clear up a few frames worth of garbage left at the top of the stack. */
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/* This is used to prevent us from accidentally treating garbade left */
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/* on the stack by other parts of the collector as roots. This */
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/* differs from the code in misc.c, which actually tries to keep the */
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/* stack clear of long-lived, client-generated garbage. */
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void GC_clear_a_few_frames()
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{
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# define NWORDS 64
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word frames[NWORDS];
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register int i;
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for (i = 0; i < NWORDS; i++) frames[i] = 0;
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}
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/* Have we allocated enough to amortize a collection? */
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GC_bool GC_should_collect()
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{
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return(GC_adj_words_allocd() >= min_words_allocd());
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}
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void GC_notify_full_gc()
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{
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if (GC_start_call_back != (void (*)())0) {
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(*GC_start_call_back)();
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}
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}
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/*
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* Initiate a garbage collection if appropriate.
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* Choose judiciously
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* between partial, full, and stop-world collections.
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* Assumes lock held, signals disabled.
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*/
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void GC_maybe_gc()
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{
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static int n_partial_gcs = 0;
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GC_bool is_full_gc = FALSE;
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if (GC_should_collect()) {
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if (!GC_incremental) {
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GC_notify_full_gc();
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GC_gcollect_inner();
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n_partial_gcs = 0;
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return;
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} else if (n_partial_gcs >= GC_full_freq) {
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# ifdef PRINTSTATS
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GC_printf2(
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"***>Full mark for collection %lu after %ld allocd bytes\n",
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(unsigned long) GC_gc_no+1,
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(long)WORDS_TO_BYTES(GC_words_allocd));
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# endif
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GC_promote_black_lists();
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(void)GC_reclaim_all((GC_stop_func)0, TRUE);
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GC_clear_marks();
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n_partial_gcs = 0;
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GC_notify_full_gc();
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is_full_gc = TRUE;
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} else {
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n_partial_gcs++;
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}
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/* We try to mark with the world stopped. */
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/* If we run out of time, this turns into */
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/* incremental marking. */
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GET_TIME(GC_start_time);
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if (GC_stopped_mark(GC_timeout_stop_func)) {
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# ifdef SAVE_CALL_CHAIN
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GC_save_callers(GC_last_stack);
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# endif
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GC_finish_collection();
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} else {
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if (!is_full_gc) {
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/* Count this as the first attempt */
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GC_n_attempts++;
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}
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}
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}
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}
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/*
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* Stop the world garbage collection. Assumes lock held, signals disabled.
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* If stop_func is not GC_never_stop_func, then abort if stop_func returns TRUE.
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*/
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GC_bool GC_try_to_collect_inner(stop_func)
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GC_stop_func stop_func;
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{
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if (GC_incremental && GC_collection_in_progress()) {
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# ifdef PRINTSTATS
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GC_printf0(
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"GC_try_to_collect_inner: finishing collection in progress\n");
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# endif /* PRINTSTATS */
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/* Just finish collection already in progress. */
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while(GC_collection_in_progress()) {
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if (stop_func()) return(FALSE);
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GC_collect_a_little_inner(1);
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}
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}
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# ifdef PRINTSTATS
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GC_printf2(
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"Initiating full world-stop collection %lu after %ld allocd bytes\n",
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(unsigned long) GC_gc_no+1,
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(long)WORDS_TO_BYTES(GC_words_allocd));
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# endif
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GC_promote_black_lists();
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/* Make sure all blocks have been reclaimed, so sweep routines */
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/* don't see cleared mark bits. */
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/* If we're guaranteed to finish, then this is unnecessary. */
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if (stop_func != GC_never_stop_func
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&& !GC_reclaim_all(stop_func, FALSE)) {
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/* Aborted. So far everything is still consistent. */
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return(FALSE);
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}
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GC_invalidate_mark_state(); /* Flush mark stack. */
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GC_clear_marks();
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# ifdef SAVE_CALL_CHAIN
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GC_save_callers(GC_last_stack);
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# endif
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if (!GC_stopped_mark(stop_func)) {
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if (!GC_incremental) {
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/* We're partially done and have no way to complete or use */
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/* current work. Reestablish invariants as cheaply as */
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/* possible. */
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GC_invalidate_mark_state();
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GC_unpromote_black_lists();
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} /* else we claim the world is already still consistent. We'll */
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/* finish incrementally. */
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return(FALSE);
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}
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GC_finish_collection();
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return(TRUE);
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}
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/*
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* Perform n units of garbage collection work. A unit is intended to touch
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* roughly GC_RATE pages. Every once in a while, we do more than that.
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* This needa to be a fairly large number with our current incremental
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* GC strategy, since otherwise we allocate too much during GC, and the
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* cleanup gets expensive.
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*/
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# define GC_RATE 10
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# define MAX_PRIOR_ATTEMPTS 1
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/* Maximum number of prior attempts at world stop marking */
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/* A value of 1 means that we finish the seconf time, no matter */
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/* how long it takes. Doesn't count the initial root scan */
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/* for a full GC. */
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int GC_deficit = 0; /* The number of extra calls to GC_mark_some */
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/* that we have made. */
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void GC_collect_a_little_inner(n)
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int n;
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{
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register int i;
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if (GC_incremental && GC_collection_in_progress()) {
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for (i = GC_deficit; i < GC_RATE*n; i++) {
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if (GC_mark_some((ptr_t)0)) {
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/* Need to finish a collection */
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# ifdef SAVE_CALL_CHAIN
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GC_save_callers(GC_last_stack);
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# endif
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if (GC_n_attempts < MAX_PRIOR_ATTEMPTS) {
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GET_TIME(GC_start_time);
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if (!GC_stopped_mark(GC_timeout_stop_func)) {
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GC_n_attempts++;
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break;
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}
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} else {
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(void)GC_stopped_mark(GC_never_stop_func);
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}
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GC_finish_collection();
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break;
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}
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}
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if (GC_deficit > 0) GC_deficit -= GC_RATE*n;
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if (GC_deficit < 0) GC_deficit = 0;
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} else {
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GC_maybe_gc();
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}
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}
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int GC_collect_a_little GC_PROTO(())
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{
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int result;
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DCL_LOCK_STATE;
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DISABLE_SIGNALS();
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LOCK();
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GC_collect_a_little_inner(1);
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result = (int)GC_collection_in_progress();
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UNLOCK();
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ENABLE_SIGNALS();
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return(result);
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}
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/*
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* Assumes lock is held, signals are disabled.
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* We stop the world.
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* If stop_func() ever returns TRUE, we may fail and return FALSE.
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* Increment GC_gc_no if we succeed.
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*/
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GC_bool GC_stopped_mark(stop_func)
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GC_stop_func stop_func;
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{
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register int i;
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int dummy;
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# ifdef PRINTSTATS
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CLOCK_TYPE start_time, current_time;
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# endif
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STOP_WORLD();
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# ifdef PRINTSTATS
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GET_TIME(start_time);
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GC_printf1("--> Marking for collection %lu ",
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(unsigned long) GC_gc_no + 1);
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GC_printf2("after %lu allocd bytes + %lu wasted bytes\n",
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(unsigned long) WORDS_TO_BYTES(GC_words_allocd),
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(unsigned long) WORDS_TO_BYTES(GC_words_wasted));
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# endif
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/* Mark from all roots. */
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/* Minimize junk left in my registers and on the stack */
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GC_clear_a_few_frames();
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GC_noop(0,0,0,0,0,0);
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GC_initiate_gc();
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for(i = 0;;i++) {
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if ((*stop_func)()) {
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# ifdef PRINTSTATS
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GC_printf0("Abandoned stopped marking after ");
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GC_printf1("%lu iterations\n",
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(unsigned long)i);
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# endif
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GC_deficit = i; /* Give the mutator a chance. */
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START_WORLD();
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return(FALSE);
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}
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||
|
if (GC_mark_some((ptr_t)(&dummy))) break;
|
||
|
}
|
||
|
|
||
|
GC_gc_no++;
|
||
|
# ifdef PRINTSTATS
|
||
|
GC_printf2("Collection %lu reclaimed %ld bytes",
|
||
|
(unsigned long) GC_gc_no - 1,
|
||
|
(long)WORDS_TO_BYTES(GC_mem_found));
|
||
|
GC_printf1(" ---> heapsize = %lu bytes\n",
|
||
|
(unsigned long) GC_heapsize);
|
||
|
/* Printf arguments may be pushed in funny places. Clear the */
|
||
|
/* space. */
|
||
|
GC_printf0("");
|
||
|
# endif
|
||
|
|
||
|
/* Check all debugged objects for consistency */
|
||
|
if (GC_debugging_started) {
|
||
|
(*GC_check_heap)();
|
||
|
}
|
||
|
|
||
|
# ifdef PRINTTIMES
|
||
|
GET_TIME(current_time);
|
||
|
GC_printf1("World-stopped marking took %lu msecs\n",
|
||
|
MS_TIME_DIFF(current_time,start_time));
|
||
|
# endif
|
||
|
START_WORLD();
|
||
|
return(TRUE);
|
||
|
}
|
||
|
|
||
|
|
||
|
/* Finish up a collection. Assumes lock is held, signals are disabled, */
|
||
|
/* but the world is otherwise running. */
|
||
|
void GC_finish_collection()
|
||
|
{
|
||
|
# ifdef PRINTTIMES
|
||
|
CLOCK_TYPE start_time;
|
||
|
CLOCK_TYPE finalize_time;
|
||
|
CLOCK_TYPE done_time;
|
||
|
|
||
|
GET_TIME(start_time);
|
||
|
finalize_time = start_time;
|
||
|
# endif
|
||
|
|
||
|
# ifdef GATHERSTATS
|
||
|
GC_mem_found = 0;
|
||
|
# endif
|
||
|
# ifdef FIND_LEAK
|
||
|
/* Mark all objects on the free list. All objects should be */
|
||
|
/* marked when we're done. */
|
||
|
{
|
||
|
register word size; /* current object size */
|
||
|
register ptr_t p; /* pointer to current object */
|
||
|
register struct hblk * h; /* pointer to block containing *p */
|
||
|
register hdr * hhdr;
|
||
|
register int word_no; /* "index" of *p in *q */
|
||
|
int kind;
|
||
|
|
||
|
for (kind = 0; kind < GC_n_kinds; kind++) {
|
||
|
for (size = 1; size <= MAXOBJSZ; size++) {
|
||
|
for (p= GC_obj_kinds[kind].ok_freelist[size];
|
||
|
p != 0; p=obj_link(p)){
|
||
|
h = HBLKPTR(p);
|
||
|
hhdr = HDR(h);
|
||
|
word_no = (((word *)p) - ((word *)h));
|
||
|
set_mark_bit_from_hdr(hhdr, word_no);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
/* Check that everything is marked */
|
||
|
GC_start_reclaim(TRUE);
|
||
|
# else
|
||
|
|
||
|
GC_finalize();
|
||
|
# ifdef STUBBORN_ALLOC
|
||
|
GC_clean_changing_list();
|
||
|
# endif
|
||
|
|
||
|
# ifdef PRINTTIMES
|
||
|
GET_TIME(finalize_time);
|
||
|
# endif
|
||
|
|
||
|
/* Clear free list mark bits, in case they got accidentally marked */
|
||
|
/* Note: HBLKPTR(p) == pointer to head of block containing *p */
|
||
|
/* Also subtract memory remaining from GC_mem_found count. */
|
||
|
/* Note that composite objects on free list are cleared. */
|
||
|
/* Thus accidentally marking a free list is not a problem; only */
|
||
|
/* objects on the list itself will be marked, and that's fixed here. */
|
||
|
{
|
||
|
register word size; /* current object size */
|
||
|
register ptr_t p; /* pointer to current object */
|
||
|
register struct hblk * h; /* pointer to block containing *p */
|
||
|
register hdr * hhdr;
|
||
|
register int word_no; /* "index" of *p in *q */
|
||
|
int kind;
|
||
|
|
||
|
for (kind = 0; kind < GC_n_kinds; kind++) {
|
||
|
for (size = 1; size <= MAXOBJSZ; size++) {
|
||
|
for (p= GC_obj_kinds[kind].ok_freelist[size];
|
||
|
p != 0; p=obj_link(p)){
|
||
|
h = HBLKPTR(p);
|
||
|
hhdr = HDR(h);
|
||
|
word_no = (((word *)p) - ((word *)h));
|
||
|
clear_mark_bit_from_hdr(hhdr, word_no);
|
||
|
# ifdef GATHERSTATS
|
||
|
GC_mem_found -= size;
|
||
|
# endif
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
|
||
|
# ifdef PRINTSTATS
|
||
|
GC_printf1("Bytes recovered before sweep - f.l. count = %ld\n",
|
||
|
(long)WORDS_TO_BYTES(GC_mem_found));
|
||
|
# endif
|
||
|
|
||
|
/* Reconstruct free lists to contain everything not marked */
|
||
|
GC_start_reclaim(FALSE);
|
||
|
|
||
|
# endif /* !FIND_LEAK */
|
||
|
|
||
|
# ifdef PRINTSTATS
|
||
|
GC_printf2(
|
||
|
"Immediately reclaimed %ld bytes in heap of size %lu bytes\n",
|
||
|
(long)WORDS_TO_BYTES(GC_mem_found),
|
||
|
(unsigned long)GC_heapsize);
|
||
|
GC_printf2("%lu (atomic) + %lu (composite) collectable bytes in use\n",
|
||
|
(unsigned long)WORDS_TO_BYTES(GC_atomic_in_use),
|
||
|
(unsigned long)WORDS_TO_BYTES(GC_composite_in_use));
|
||
|
# endif
|
||
|
|
||
|
GC_n_attempts = 0;
|
||
|
/* Reset or increment counters for next cycle */
|
||
|
GC_words_allocd_before_gc += GC_words_allocd;
|
||
|
GC_non_gc_bytes_at_gc = GC_non_gc_bytes;
|
||
|
GC_words_allocd = 0;
|
||
|
GC_words_wasted = 0;
|
||
|
GC_mem_freed = 0;
|
||
|
|
||
|
# ifdef PRINTTIMES
|
||
|
GET_TIME(done_time);
|
||
|
GC_printf2("Finalize + initiate sweep took %lu + %lu msecs\n",
|
||
|
MS_TIME_DIFF(finalize_time,start_time),
|
||
|
MS_TIME_DIFF(done_time,finalize_time));
|
||
|
# endif
|
||
|
}
|
||
|
|
||
|
/* Externally callable routine to invoke full, stop-world collection */
|
||
|
# if defined(__STDC__) || defined(__cplusplus)
|
||
|
int GC_try_to_collect(GC_stop_func stop_func)
|
||
|
# else
|
||
|
int GC_try_to_collect(stop_func)
|
||
|
GC_stop_func stop_func;
|
||
|
# endif
|
||
|
{
|
||
|
int result;
|
||
|
DCL_LOCK_STATE;
|
||
|
|
||
|
GC_INVOKE_FINALIZERS();
|
||
|
DISABLE_SIGNALS();
|
||
|
LOCK();
|
||
|
ENTER_GC();
|
||
|
if (!GC_is_initialized) GC_init_inner();
|
||
|
/* Minimize junk left in my registers */
|
||
|
GC_noop(0,0,0,0,0,0);
|
||
|
result = (int)GC_try_to_collect_inner(stop_func);
|
||
|
EXIT_GC();
|
||
|
UNLOCK();
|
||
|
ENABLE_SIGNALS();
|
||
|
if(result) GC_INVOKE_FINALIZERS();
|
||
|
return(result);
|
||
|
}
|
||
|
|
||
|
void GC_gcollect GC_PROTO(())
|
||
|
{
|
||
|
GC_notify_full_gc();
|
||
|
(void)GC_try_to_collect(GC_never_stop_func);
|
||
|
}
|
||
|
|
||
|
word GC_n_heap_sects = 0; /* Number of sections currently in heap. */
|
||
|
|
||
|
/*
|
||
|
* Use the chunk of memory starting at p of syze bytes as part of the heap.
|
||
|
* Assumes p is HBLKSIZE aligned, and bytes is a multiple of HBLKSIZE.
|
||
|
*/
|
||
|
void GC_add_to_heap(p, bytes)
|
||
|
struct hblk *p;
|
||
|
word bytes;
|
||
|
{
|
||
|
word words;
|
||
|
|
||
|
if (GC_n_heap_sects >= MAX_HEAP_SECTS) {
|
||
|
ABORT("Too many heap sections: Increase MAXHINCR or MAX_HEAP_SECTS");
|
||
|
}
|
||
|
if (!GC_install_header(p)) {
|
||
|
/* This is extremely unlikely. Can't add it. This will */
|
||
|
/* almost certainly result in a 0 return from the allocator, */
|
||
|
/* which is entirely appropriate. */
|
||
|
return;
|
||
|
}
|
||
|
GC_heap_sects[GC_n_heap_sects].hs_start = (ptr_t)p;
|
||
|
GC_heap_sects[GC_n_heap_sects].hs_bytes = bytes;
|
||
|
GC_n_heap_sects++;
|
||
|
words = BYTES_TO_WORDS(bytes - HDR_BYTES);
|
||
|
HDR(p) -> hb_sz = words;
|
||
|
GC_freehblk(p);
|
||
|
GC_heapsize += bytes;
|
||
|
if ((ptr_t)p <= GC_least_plausible_heap_addr
|
||
|
|| GC_least_plausible_heap_addr == 0) {
|
||
|
GC_least_plausible_heap_addr = (ptr_t)p - sizeof(word);
|
||
|
/* Making it a little smaller than necessary prevents */
|
||
|
/* us from getting a false hit from the variable */
|
||
|
/* itself. There's some unintentional reflection */
|
||
|
/* here. */
|
||
|
}
|
||
|
if ((ptr_t)p + bytes >= GC_greatest_plausible_heap_addr) {
|
||
|
GC_greatest_plausible_heap_addr = (ptr_t)p + bytes;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
#ifdef PRESERVE_LAST
|
||
|
|
||
|
GC_bool GC_protect_last_block = FALSE;
|
||
|
|
||
|
GC_bool GC_in_last_heap_sect(p)
|
||
|
ptr_t p;
|
||
|
{
|
||
|
struct HeapSect * last_heap_sect;
|
||
|
ptr_t start;
|
||
|
ptr_t end;
|
||
|
|
||
|
if (!GC_protect_last_block) return FALSE;
|
||
|
last_heap_sect = &(GC_heap_sects[GC_n_heap_sects-1]);
|
||
|
start = last_heap_sect -> hs_start;
|
||
|
if (p < start) return FALSE;
|
||
|
end = start + last_heap_sect -> hs_bytes;
|
||
|
if (p >= end) return FALSE;
|
||
|
return TRUE;
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
# if !defined(NO_DEBUGGING)
|
||
|
void GC_print_heap_sects()
|
||
|
{
|
||
|
register unsigned i;
|
||
|
|
||
|
GC_printf1("Total heap size: %lu\n", (unsigned long) GC_heapsize);
|
||
|
for (i = 0; i < GC_n_heap_sects; i++) {
|
||
|
unsigned long start = (unsigned long) GC_heap_sects[i].hs_start;
|
||
|
unsigned long len = (unsigned long) GC_heap_sects[i].hs_bytes;
|
||
|
struct hblk *h;
|
||
|
unsigned nbl = 0;
|
||
|
|
||
|
GC_printf3("Section %ld from 0x%lx to 0x%lx ", (unsigned long)i,
|
||
|
start, (unsigned long)(start + len));
|
||
|
for (h = (struct hblk *)start; h < (struct hblk *)(start + len); h++) {
|
||
|
if (GC_is_black_listed(h, HBLKSIZE)) nbl++;
|
||
|
}
|
||
|
GC_printf2("%lu/%lu blacklisted\n", (unsigned long)nbl,
|
||
|
(unsigned long)(len/HBLKSIZE));
|
||
|
}
|
||
|
}
|
||
|
# endif
|
||
|
|
||
|
ptr_t GC_least_plausible_heap_addr = (ptr_t)ONES;
|
||
|
ptr_t GC_greatest_plausible_heap_addr = 0;
|
||
|
|
||
|
ptr_t GC_max(x,y)
|
||
|
ptr_t x, y;
|
||
|
{
|
||
|
return(x > y? x : y);
|
||
|
}
|
||
|
|
||
|
ptr_t GC_min(x,y)
|
||
|
ptr_t x, y;
|
||
|
{
|
||
|
return(x < y? x : y);
|
||
|
}
|
||
|
|
||
|
# if defined(__STDC__) || defined(__cplusplus)
|
||
|
void GC_set_max_heap_size(GC_word n)
|
||
|
# else
|
||
|
void GC_set_max_heap_size(n)
|
||
|
GC_word n;
|
||
|
# endif
|
||
|
{
|
||
|
GC_max_heapsize = n;
|
||
|
}
|
||
|
|
||
|
GC_word GC_max_retries = 0;
|
||
|
|
||
|
/*
|
||
|
* this explicitly increases the size of the heap. It is used
|
||
|
* internally, but may also be invoked from GC_expand_hp by the user.
|
||
|
* The argument is in units of HBLKSIZE.
|
||
|
* Tiny values of n are rounded up.
|
||
|
* Returns FALSE on failure.
|
||
|
*/
|
||
|
GC_bool GC_expand_hp_inner(n)
|
||
|
word n;
|
||
|
{
|
||
|
word bytes;
|
||
|
struct hblk * space;
|
||
|
word expansion_slop; /* Number of bytes by which we expect the */
|
||
|
/* heap to expand soon. */
|
||
|
|
||
|
if (n < MINHINCR) n = MINHINCR;
|
||
|
bytes = n * HBLKSIZE;
|
||
|
/* Make sure bytes is a multiple of GC_page_size */
|
||
|
{
|
||
|
word mask = GC_page_size - 1;
|
||
|
bytes += mask;
|
||
|
bytes &= ~mask;
|
||
|
}
|
||
|
|
||
|
if (GC_max_heapsize != 0 && GC_heapsize + bytes > GC_max_heapsize) {
|
||
|
/* Exceeded self-imposed limit */
|
||
|
return(FALSE);
|
||
|
}
|
||
|
space = GET_MEM(bytes);
|
||
|
if( space == 0 ) {
|
||
|
return(FALSE);
|
||
|
}
|
||
|
# ifdef PRINTSTATS
|
||
|
GC_printf2("Increasing heap size by %lu after %lu allocated bytes\n",
|
||
|
(unsigned long)bytes,
|
||
|
(unsigned long)WORDS_TO_BYTES(GC_words_allocd));
|
||
|
# ifdef UNDEFINED
|
||
|
GC_printf1("Root size = %lu\n", GC_root_size);
|
||
|
GC_print_block_list(); GC_print_hblkfreelist();
|
||
|
GC_printf0("\n");
|
||
|
# endif
|
||
|
# endif
|
||
|
expansion_slop = 8 * WORDS_TO_BYTES(min_words_allocd());
|
||
|
if (5 * HBLKSIZE * MAXHINCR > expansion_slop) {
|
||
|
expansion_slop = 5 * HBLKSIZE * MAXHINCR;
|
||
|
}
|
||
|
if (GC_last_heap_addr == 0 && !((word)space & SIGNB)
|
||
|
|| GC_last_heap_addr != 0 && GC_last_heap_addr < (ptr_t)space) {
|
||
|
/* Assume the heap is growing up */
|
||
|
GC_greatest_plausible_heap_addr =
|
||
|
GC_max(GC_greatest_plausible_heap_addr,
|
||
|
(ptr_t)space + bytes + expansion_slop);
|
||
|
} else {
|
||
|
/* Heap is growing down */
|
||
|
GC_least_plausible_heap_addr =
|
||
|
GC_min(GC_least_plausible_heap_addr,
|
||
|
(ptr_t)space - expansion_slop);
|
||
|
}
|
||
|
GC_prev_heap_addr = GC_last_heap_addr;
|
||
|
GC_last_heap_addr = (ptr_t)space;
|
||
|
GC_add_to_heap(space, bytes);
|
||
|
return(TRUE);
|
||
|
}
|
||
|
|
||
|
/* Really returns a bool, but it's externally visible, so that's clumsy. */
|
||
|
/* Arguments is in bytes. */
|
||
|
# if defined(__STDC__) || defined(__cplusplus)
|
||
|
int GC_expand_hp(size_t bytes)
|
||
|
# else
|
||
|
int GC_expand_hp(bytes)
|
||
|
size_t bytes;
|
||
|
# endif
|
||
|
{
|
||
|
int result;
|
||
|
DCL_LOCK_STATE;
|
||
|
|
||
|
DISABLE_SIGNALS();
|
||
|
LOCK();
|
||
|
if (!GC_is_initialized) GC_init_inner();
|
||
|
result = (int)GC_expand_hp_inner(divHBLKSZ((word)bytes));
|
||
|
# ifdef PRESERVE_LAST
|
||
|
if (result) GC_protect_last_block = FALSE;
|
||
|
# endif
|
||
|
UNLOCK();
|
||
|
ENABLE_SIGNALS();
|
||
|
return(result);
|
||
|
}
|
||
|
|
||
|
unsigned GC_fail_count = 0;
|
||
|
/* How many consecutive GC/expansion failures? */
|
||
|
/* Reset by GC_allochblk. */
|
||
|
|
||
|
GC_bool GC_collect_or_expand(needed_blocks, ignore_off_page)
|
||
|
word needed_blocks;
|
||
|
GC_bool ignore_off_page;
|
||
|
{
|
||
|
|
||
|
if (!GC_incremental && !GC_dont_gc && GC_should_collect()) {
|
||
|
GC_notify_full_gc();
|
||
|
GC_gcollect_inner();
|
||
|
} else {
|
||
|
word blocks_to_get = GC_heapsize/(HBLKSIZE*GC_free_space_divisor)
|
||
|
+ needed_blocks;
|
||
|
|
||
|
if (blocks_to_get > MAXHINCR) {
|
||
|
word slop;
|
||
|
|
||
|
if (ignore_off_page) {
|
||
|
slop = 4;
|
||
|
} else {
|
||
|
slop = 2*divHBLKSZ(BL_LIMIT);
|
||
|
if (slop > needed_blocks) slop = needed_blocks;
|
||
|
}
|
||
|
if (needed_blocks + slop > MAXHINCR) {
|
||
|
blocks_to_get = needed_blocks + slop;
|
||
|
} else {
|
||
|
blocks_to_get = MAXHINCR;
|
||
|
}
|
||
|
}
|
||
|
if (!GC_expand_hp_inner(blocks_to_get)
|
||
|
&& !GC_expand_hp_inner(needed_blocks)) {
|
||
|
if (GC_fail_count++ < GC_max_retries) {
|
||
|
WARN("Out of Memory! Trying to continue ...\n", 0);
|
||
|
GC_notify_full_gc();
|
||
|
GC_gcollect_inner();
|
||
|
} else {
|
||
|
WARN("Out of Memory! Returning NIL!\n", 0);
|
||
|
return(FALSE);
|
||
|
}
|
||
|
} else {
|
||
|
# ifdef PRINTSTATS
|
||
|
if (GC_fail_count) {
|
||
|
GC_printf0("Memory available again ...\n");
|
||
|
}
|
||
|
# endif
|
||
|
# ifdef PRESERVE_LAST
|
||
|
if (needed_blocks > 1) GC_protect_last_block = TRUE;
|
||
|
/* We were forced to expand the heap as the result */
|
||
|
/* of a large block allocation. Avoid breaking up */
|
||
|
/* new block into small pieces. */
|
||
|
# endif
|
||
|
}
|
||
|
}
|
||
|
return(TRUE);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Make sure the object free list for sz is not empty.
|
||
|
* Return a pointer to the first object on the free list.
|
||
|
* The object MUST BE REMOVED FROM THE FREE LIST BY THE CALLER.
|
||
|
* Assumes we hold the allocator lock and signals are disabled.
|
||
|
*
|
||
|
*/
|
||
|
ptr_t GC_allocobj(sz, kind)
|
||
|
word sz;
|
||
|
int kind;
|
||
|
{
|
||
|
register ptr_t * flh = &(GC_obj_kinds[kind].ok_freelist[sz]);
|
||
|
|
||
|
if (sz == 0) return(0);
|
||
|
|
||
|
while (*flh == 0) {
|
||
|
ENTER_GC();
|
||
|
/* Do our share of marking work */
|
||
|
if(GC_incremental && !GC_dont_gc) GC_collect_a_little_inner(1);
|
||
|
/* Sweep blocks for objects of this size */
|
||
|
GC_continue_reclaim(sz, kind);
|
||
|
EXIT_GC();
|
||
|
if (*flh == 0) {
|
||
|
GC_new_hblk(sz, kind);
|
||
|
}
|
||
|
if (*flh == 0) {
|
||
|
ENTER_GC();
|
||
|
if (!GC_collect_or_expand((word)1,FALSE)) {
|
||
|
EXIT_GC();
|
||
|
return(0);
|
||
|
}
|
||
|
EXIT_GC();
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return(*flh);
|
||
|
}
|