diff options
Diffstat (limited to 'boehm-gc/alloc.c')
| -rw-r--r-- | boehm-gc/alloc.c | 212 |
1 files changed, 134 insertions, 78 deletions
diff --git a/boehm-gc/alloc.c b/boehm-gc/alloc.c index c9d145e0369..3d0ddf05b36 100644 --- a/boehm-gc/alloc.c +++ b/boehm-gc/alloc.c @@ -1,6 +1,8 @@ /* * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers - * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. + * Copyright (c) 1991-1996 by Xerox Corporation. All rights reserved. + * Copyright (c) 1998 by Silicon Graphics. All rights reserved. + * Copyright (c) 1999 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. @@ -12,7 +14,6 @@ * modified is included with the above copyright notice. * */ -/* Boehm, February 16, 1996 2:26 pm PST */ # include "gc_priv.h" @@ -58,15 +59,25 @@ word GC_non_gc_bytes = 0; /* Number of bytes not intended to be collected */ word GC_gc_no = 0; -int GC_incremental = 0; /* By default, stop the world. */ +#ifndef SMALL_CONFIG + int GC_incremental = 0; /* By default, stop the world. */ +#endif + +int GC_full_freq = 19; /* Every 20th collection is a full */ + /* collection, whether we need it */ + /* or not. */ + +GC_bool GC_need_full_gc = FALSE; + /* Need full GC do to heap growth. */ -int GC_full_freq = 4; /* Every 5th collection is a full */ - /* collection. */ +#define USED_HEAP_SIZE (GC_heapsize - GC_large_free_bytes) + +word GC_used_heap_size_after_full = 0; char * GC_copyright[] = {"Copyright 1988,1989 Hans-J. Boehm and Alan J. Demers ", "Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved. ", -"Copyright (c) 1996-1997 by Silicon Graphics. All rights reserved. ", +"Copyright (c) 1996-1998 by Silicon Graphics. All rights reserved. ", "THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY", " EXPRESSED OR IMPLIED. ANY USE IS AT YOUR OWN RISK.", "See source code for details." }; @@ -80,16 +91,24 @@ extern signed_word GC_mem_found; /* Number of reclaimed longwords */ GC_bool GC_dont_expand = 0; -word GC_free_space_divisor = 4; +word GC_free_space_divisor = 3; extern GC_bool GC_collection_in_progress(); + /* Collection is in progress, or was abandoned. */ int GC_never_stop_func GC_PROTO((void)) { return(0); } -CLOCK_TYPE GC_start_time; +CLOCK_TYPE GC_start_time; /* Time at which we stopped world. */ + /* used only in GC_timeout_stop_func. */ -int GC_timeout_stop_func GC_PROTO((void)) -{ +int GC_n_attempts = 0; /* Number of attempts at finishing */ + /* collection within TIME_LIMIT */ + +#ifdef SMALL_CONFIG +# define GC_timeout_stop_func GC_never_stop_func +#else + int GC_timeout_stop_func GC_PROTO((void)) + { CLOCK_TYPE current_time; static unsigned count = 0; unsigned long time_diff; @@ -101,13 +120,15 @@ int GC_timeout_stop_func GC_PROTO((void)) if (time_diff >= TIME_LIMIT) { # ifdef PRINTSTATS GC_printf0("Abandoning stopped marking after "); - GC_printf1("%lu msecs\n", (unsigned long)time_diff); + GC_printf1("%lu msecs", (unsigned long)time_diff); + GC_printf1("(attempt %d)\n", (unsigned long) GC_n_attempts); # endif return(1); } #endif return(0); -} + } +#endif /* !SMALL_CONFIG */ /* Return the minimum number of words that must be allocated between */ /* collections to amortize the collection cost. */ @@ -120,18 +141,22 @@ static word min_words_allocd() int dummy; register signed_word stack_size = (ptr_t)(&dummy) - GC_stackbottom; # endif - register word total_root_size; /* includes double stack size, */ + word total_root_size; /* includes double stack size, */ /* since the stack is expensive */ /* to scan. */ + word scan_size; /* Estimate of memory to be scanned */ + /* during normal GC. */ if (stack_size < 0) stack_size = -stack_size; total_root_size = 2 * stack_size + GC_root_size; + scan_size = BYTES_TO_WORDS(GC_heapsize - GC_large_free_bytes + + (GC_large_free_bytes >> 2) + /* use a bit more of large empty heap */ + + total_root_size); if (GC_incremental) { - return(BYTES_TO_WORDS(GC_heapsize + total_root_size) - / (2 * GC_free_space_divisor)); + return scan_size / (2 * GC_free_space_divisor); } else { - return(BYTES_TO_WORDS(GC_heapsize + total_root_size) - / GC_free_space_divisor); + return scan_size / GC_free_space_divisor; } } @@ -196,6 +221,7 @@ GC_bool GC_should_collect() return(GC_adj_words_allocd() >= min_words_allocd()); } + void GC_notify_full_gc() { if (GC_start_call_back != (void (*)())0) { @@ -203,6 +229,8 @@ void GC_notify_full_gc() } } +GC_bool GC_is_full_gc = FALSE; + /* * Initiate a garbage collection if appropriate. * Choose judiciously @@ -212,13 +240,14 @@ void GC_notify_full_gc() void GC_maybe_gc() { static int n_partial_gcs = 0; + if (GC_should_collect()) { if (!GC_incremental) { GC_notify_full_gc(); GC_gcollect_inner(); n_partial_gcs = 0; return; - } else if (n_partial_gcs >= GC_full_freq) { + } else if (GC_need_full_gc || n_partial_gcs >= GC_full_freq) { # ifdef PRINTSTATS GC_printf2( "***>Full mark for collection %lu after %ld allocd bytes\n", @@ -230,6 +259,7 @@ void GC_maybe_gc() GC_clear_marks(); n_partial_gcs = 0; GC_notify_full_gc(); + GC_is_full_gc = TRUE; } else { n_partial_gcs++; } @@ -244,7 +274,12 @@ void GC_maybe_gc() GC_save_callers(GC_last_stack); # endif GC_finish_collection(); - } + } else { + if (!GC_is_full_gc) { + /* Count this as the first attempt */ + GC_n_attempts++; + } + } } } @@ -256,7 +291,7 @@ void GC_maybe_gc() GC_bool GC_try_to_collect_inner(stop_func) GC_stop_func stop_func; { - if (GC_collection_in_progress()) { + if (GC_incremental && GC_collection_in_progress()) { # ifdef PRINTSTATS GC_printf0( "GC_try_to_collect_inner: finishing collection in progress\n"); @@ -287,6 +322,7 @@ GC_stop_func stop_func; # ifdef SAVE_CALL_CHAIN GC_save_callers(GC_last_stack); # endif + GC_is_full_gc = TRUE; if (!GC_stopped_mark(stop_func)) { if (!GC_incremental) { /* We're partially done and have no way to complete or use */ @@ -306,32 +342,48 @@ GC_stop_func stop_func; /* * Perform n units of garbage collection work. A unit is intended to touch - * roughly a GC_RATE pages. Every once in a while, we do more than that. + * roughly GC_RATE pages. Every once in a while, we do more than that. + * This needa to be a fairly large number with our current incremental + * GC strategy, since otherwise we allocate too much during GC, and the + * cleanup gets expensive. */ -# define GC_RATE 8 +# define GC_RATE 10 +# define MAX_PRIOR_ATTEMPTS 1 + /* Maximum number of prior attempts at world stop marking */ + /* A value of 1 means that we finish the seconf time, no matter */ + /* how long it takes. Doesn't count the initial root scan */ + /* for a full GC. */ int GC_deficit = 0; /* The number of extra calls to GC_mark_some */ /* that we have made. */ - /* Negative values are equivalent to 0. */ void GC_collect_a_little_inner(n) int n; { register int i; - if (GC_collection_in_progress()) { + if (GC_incremental && GC_collection_in_progress()) { for (i = GC_deficit; i < GC_RATE*n; i++) { - if (GC_mark_some()) { + if (GC_mark_some((ptr_t)0)) { /* Need to finish a collection */ # ifdef SAVE_CALL_CHAIN GC_save_callers(GC_last_stack); # endif - (void) GC_stopped_mark(GC_never_stop_func); + if (GC_n_attempts < MAX_PRIOR_ATTEMPTS) { + GET_TIME(GC_start_time); + if (!GC_stopped_mark(GC_timeout_stop_func)) { + GC_n_attempts++; + break; + } + } else { + (void)GC_stopped_mark(GC_never_stop_func); + } GC_finish_collection(); break; } } if (GC_deficit > 0) GC_deficit -= GC_RATE*n; + if (GC_deficit < 0) GC_deficit = 0; } else { GC_maybe_gc(); } @@ -354,15 +406,14 @@ int GC_collect_a_little GC_PROTO(()) /* * Assumes lock is held, signals are disabled. * We stop the world. - * If final is TRUE, then we finish the collection, no matter how long - * it takes. - * Otherwise we may fail and return FALSE if this takes too long. + * If stop_func() ever returns TRUE, we may fail and return FALSE. * Increment GC_gc_no if we succeed. */ GC_bool GC_stopped_mark(stop_func) GC_stop_func stop_func; { register int i; + int dummy; # ifdef PRINTSTATS CLOCK_TYPE start_time, current_time; # endif @@ -393,7 +444,7 @@ GC_stop_func stop_func; START_WORLD(); return(FALSE); } - if (GC_mark_some()) break; + if (GC_mark_some((ptr_t)(&dummy))) break; } GC_gc_no++; @@ -439,7 +490,7 @@ void GC_finish_collection() # ifdef GATHERSTATS GC_mem_found = 0; # endif -# ifdef FIND_LEAK + if (GC_find_leak) { /* Mark all objects on the free list. All objects should be */ /* marked when we're done. */ { @@ -462,25 +513,26 @@ void GC_finish_collection() } } } - /* Check that everything is marked */ GC_start_reclaim(TRUE); -# else + /* The above just checks; it doesn't really reclaim anything. */ + } + + GC_finalize(); +# ifdef STUBBORN_ALLOC + GC_clean_changing_list(); +# endif - 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. */ +# 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 */ + /* (or GC_find_leak is set and they were intentionally marked.) */ + /* 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 */ @@ -506,26 +558,37 @@ void GC_finish_collection() } -# ifdef PRINTSTATS +# ifdef PRINTSTATS GC_printf1("Bytes recovered before sweep - f.l. count = %ld\n", (long)WORDS_TO_BYTES(GC_mem_found)); -# endif - +# endif /* Reconstruct free lists to contain everything not marked */ - GC_start_reclaim(FALSE); - -# endif /* !FIND_LEAK */ + GC_start_reclaim(FALSE); + if (GC_is_full_gc) { + GC_used_heap_size_after_full = USED_HEAP_SIZE; + GC_need_full_gc = FALSE; + } else { + GC_need_full_gc = + BYTES_TO_WORDS(USED_HEAP_SIZE - GC_used_heap_size_after_full) + > min_words_allocd(); + } # ifdef PRINTSTATS GC_printf2( - "Immediately reclaimed %ld bytes in heap of size %lu bytes\n", + "Immediately reclaimed %ld bytes in heap of size %lu bytes", (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)); +# ifdef USE_MUNMAP + GC_printf1("(%lu unmapped)", GC_unmapped_bytes); +# endif + GC_printf2( + "\n%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; + GC_is_full_gc = FALSE; /* 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; @@ -533,6 +596,9 @@ void GC_finish_collection() GC_words_wasted = 0; GC_mem_freed = 0; +# ifdef USE_MUNMAP + GC_unmap_old(); +# endif # ifdef PRINTTIMES GET_TIME(done_time); GC_printf2("Finalize + initiate sweep took %lu + %lu msecs\n", @@ -576,7 +642,7 @@ void GC_gcollect GC_PROTO(()) 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. + * Use the chunk of memory starting at p of size 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) @@ -584,6 +650,7 @@ struct hblk *p; word bytes; { word words; + hdr * phdr; if (GC_n_heap_sects >= MAX_HEAP_SECTS) { ABORT("Too many heap sections: Increase MAXHINCR or MAX_HEAP_SECTS"); @@ -598,7 +665,10 @@ word bytes; 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; + phdr = HDR(p); + phdr -> hb_sz = words; + phdr -> hb_map = (char *)1; /* A value != GC_invalid_map */ + phdr -> hb_flags = 0; GC_freehblk(p); GC_heapsize += bytes; if ((ptr_t)p <= GC_least_plausible_heap_addr @@ -614,21 +684,6 @@ word bytes; } } -#ifdef PRESERVE_LAST -GC_bool GC_in_last_heap_sect(p) -ptr_t p; -{ - struct HeapSect * last_heap_sect = &(GC_heap_sects[GC_n_heap_sects-1]); - ptr_t start = last_heap_sect -> hs_start; - ptr_t end; - - 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() { @@ -772,7 +827,6 @@ 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(); @@ -805,9 +859,11 @@ GC_bool ignore_off_page; WARN("Out of Memory! Returning NIL!\n", 0); return(FALSE); } - } else if (GC_fail_count) { + } else { # ifdef PRINTSTATS - GC_printf0("Memory available again ...\n"); + if (GC_fail_count) { + GC_printf0("Memory available again ...\n"); + } # endif } } |
