diff options
Diffstat (limited to '')
-rw-r--r-- | gc/allchblk.c | 181 |
1 files changed, 130 insertions, 51 deletions
diff --git a/gc/allchblk.c b/gc/allchblk.c index d8d0afd..7629672 100644 --- a/gc/allchblk.c +++ b/gc/allchblk.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) 1998-1999 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. @@ -13,11 +14,11 @@ * 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, @@ -45,6 +46,35 @@ 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? */ + 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; @@ -77,7 +107,14 @@ void GC_print_hblkfreelist() 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 (Total size %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; @@ -122,7 +159,7 @@ hdr * wanted; void GC_dump_regions() { - int i; + unsigned i; ptr_t start, end; ptr_t p; size_t bytes; @@ -217,22 +254,39 @@ void GC_remove_from_fl(hhdr, n) 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; } + INCR_FREE_BYTES(index, - (signed_word)(hhdr -> hb_sz)); + FREE_ASSERT(GC_free_bytes[index] >= 0); 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; } } @@ -243,13 +297,20 @@ struct hblk * GC_free_block_ending_at(h) 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); @@ -270,6 +331,7 @@ hdr * hhdr; { 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); @@ -280,9 +342,14 @@ hdr * hhdr; # 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); } @@ -329,10 +396,10 @@ void GC_merge_unmapped(void) 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; @@ -397,12 +464,12 @@ int index; 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) 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); @@ -446,6 +513,8 @@ int index; /* Index of free list */ 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. */ @@ -467,20 +536,23 @@ struct hblk * GC_allochblk_nth(); * 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; } @@ -505,16 +577,27 @@ int n; /* 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 (!GC_use_entire_heap + && size_avail != size_needed + && USED_HEAP_SIZE >= GC_requested_heapsize + && !GC_incremental && GC_should_collect()) { +# ifdef USE_MUNMAP continue; - } -# endif +# else + /* If we 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; + } +# 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. */ @@ -523,7 +606,7 @@ int n; 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 @@ -544,22 +627,23 @@ int n; 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; @@ -571,8 +655,10 @@ int n; && 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 (0 == GETENV("GC_NO_BLACKLIST_WARNING")) { + WARN("Needed to allocate blacklisted block at 0x%lx\n", + (word)hbp); + } size_avail = orig_avail; } else if (size_avail == 0 && size_needed == HBLKSIZE && IS_MAPPED(hhdr)) { @@ -597,14 +683,13 @@ int n; 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); } } } @@ -621,7 +706,7 @@ int n; 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 @@ -647,12 +732,6 @@ int n; 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); - } - /* We just successfully allocated a block. Restart count of */ /* consecutive failures. */ { @@ -685,7 +764,7 @@ hdr *hhdr, *prevhdr, *nexthdr; 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); @@ -700,7 +779,7 @@ signed_word size; 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)) { |