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[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [boehm-gc/] [reclaim.c] - Rev 796
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/* * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers * Copyright (c) 1991-1996 by Xerox Corporation. All rights reserved. * Copyright (c) 1996-1999 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. * * Permission is hereby granted to use or copy this program * for any purpose, provided the above notices are retained on all copies. * Permission to modify the code and to distribute modified code is granted, * provided the above notices are retained, and a notice that the code was * modified is included with the above copyright notice. */ #include <stdio.h> #include "private/gc_priv.h" signed_word GC_mem_found = 0; /* Number of words of memory reclaimed */ #if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC) word GC_fl_builder_count = 0; /* Number of threads currently building free lists without */ /* holding GC lock. It is not safe to collect if this is */ /* nonzero. */ #endif /* PARALLEL_MARK */ /* We defer printing of leaked objects until we're done with the GC */ /* cycle, since the routine for printing objects needs to run outside */ /* the collector, e.g. without the allocation lock. */ #define MAX_LEAKED 40 ptr_t GC_leaked[MAX_LEAKED]; unsigned GC_n_leaked = 0; GC_bool GC_have_errors = FALSE; void GC_add_leaked(leaked) ptr_t leaked; { if (GC_n_leaked < MAX_LEAKED) { GC_have_errors = TRUE; GC_leaked[GC_n_leaked++] = leaked; /* Make sure it's not reclaimed this cycle */ GC_set_mark_bit(leaked); } } static GC_bool printing_errors = FALSE; /* Print all objects on the list after printing any smashed objs. */ /* Clear both lists. */ void GC_print_all_errors () { unsigned i; LOCK(); if (printing_errors) { UNLOCK(); return; } printing_errors = TRUE; UNLOCK(); if (GC_debugging_started) GC_print_all_smashed(); for (i = 0; i < GC_n_leaked; ++i) { ptr_t p = GC_leaked[i]; if (HDR(p) -> hb_obj_kind == PTRFREE) { GC_err_printf0("Leaked atomic object at "); } else { GC_err_printf0("Leaked composite object at "); } GC_print_heap_obj(p); GC_err_printf0("\n"); GC_free(p); GC_leaked[i] = 0; } GC_n_leaked = 0; printing_errors = FALSE; } # define FOUND_FREE(hblk, word_no) \ { \ GC_add_leaked((ptr_t)hblk + WORDS_TO_BYTES(word_no)); \ } /* * reclaim phase * */ /* * Test whether a block is completely empty, i.e. contains no marked * objects. This does not require the block to be in physical * memory. */ GC_bool GC_block_empty(hhdr) register hdr * hhdr; { /* We treat hb_marks as an array of words here, even if it is */ /* actually an array of bytes. Since we only check for zero, there */ /* are no endian-ness issues. */ register word *p = (word *)(&(hhdr -> hb_marks[0])); register word * plim = (word *)(&(hhdr -> hb_marks[MARK_BITS_SZ])); while (p < plim) { if (*p++) return(FALSE); } return(TRUE); } /* The following functions sometimes return a DONT_KNOW value. */ #define DONT_KNOW 2 #ifdef SMALL_CONFIG # define GC_block_nearly_full1(hhdr, pat1) DONT_KNOW # define GC_block_nearly_full3(hhdr, pat1, pat2) DONT_KNOW # define GC_block_nearly_full(hhdr) DONT_KNOW #endif #if !defined(SMALL_CONFIG) && defined(USE_MARK_BYTES) # define GC_block_nearly_full1(hhdr, pat1) GC_block_nearly_full(hhdr) # define GC_block_nearly_full3(hhdr, pat1, pat2) GC_block_nearly_full(hhdr) GC_bool GC_block_nearly_full(hhdr) register hdr * hhdr; { /* We again treat hb_marks as an array of words, even though it */ /* isn't. We first sum up all the words, resulting in a word */ /* containing 4 or 8 separate partial sums. */ /* We then sum the bytes in the word of partial sums. */ /* This is still endian independant. This fails if the partial */ /* sums can overflow. */ # if (BYTES_TO_WORDS(MARK_BITS_SZ)) >= 256 --> potential overflow; fix the code # endif register word *p = (word *)(&(hhdr -> hb_marks[0])); register word * plim = (word *)(&(hhdr -> hb_marks[MARK_BITS_SZ])); word sum_vector = 0; unsigned sum; while (p < plim) { sum_vector += *p; ++p; } sum = 0; while (sum_vector > 0) { sum += sum_vector & 0xff; sum_vector >>= 8; } return (sum > BYTES_TO_WORDS(7*HBLKSIZE/8)/(hhdr -> hb_sz)); } #endif /* USE_MARK_BYTES */ #if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES) /* * Test whether nearly all of the mark words consist of the same * repeating pattern. */ #define FULL_THRESHOLD (MARK_BITS_SZ/16) GC_bool GC_block_nearly_full1(hhdr, pat1) hdr *hhdr; word pat1; { unsigned i; unsigned misses = 0; GC_ASSERT((MARK_BITS_SZ & 1) == 0); for (i = 0; i < MARK_BITS_SZ; ++i) { if ((hhdr -> hb_marks[i] | ~pat1) != ONES) { if (++misses > FULL_THRESHOLD) return FALSE; } } return TRUE; } /* * Test whether the same repeating 3 word pattern occurs in nearly * all the mark bit slots. * This is used as a heuristic, so we're a bit sloppy and ignore * the last one or two words. */ GC_bool GC_block_nearly_full3(hhdr, pat1, pat2, pat3) hdr *hhdr; word pat1, pat2, pat3; { unsigned i; unsigned misses = 0; if (MARK_BITS_SZ < 4) { return DONT_KNOW; } for (i = 0; i < MARK_BITS_SZ - 2; i += 3) { if ((hhdr -> hb_marks[i] | ~pat1) != ONES) { if (++misses > FULL_THRESHOLD) return FALSE; } if ((hhdr -> hb_marks[i+1] | ~pat2) != ONES) { if (++misses > FULL_THRESHOLD) return FALSE; } if ((hhdr -> hb_marks[i+2] | ~pat3) != ONES) { if (++misses > FULL_THRESHOLD) return FALSE; } } return TRUE; } /* Check whether a small object block is nearly full by looking at only */ /* the mark bits. */ /* We manually precomputed the mark bit patterns that need to be */ /* checked for, and we give up on the ones that are unlikely to occur, */ /* or have period > 3. */ /* This would be a lot easier with a mark bit per object instead of per */ /* word, but that would rewuire computing object numbers in the mark */ /* loop, which would require different data structures ... */ GC_bool GC_block_nearly_full(hhdr) hdr *hhdr; { int sz = hhdr -> hb_sz; # if CPP_WORDSZ != 32 && CPP_WORDSZ != 64 return DONT_KNOW; /* Shouldn't be used in any standard config. */ # endif # if CPP_WORDSZ == 32 switch(sz) { case 1: return GC_block_nearly_full1(hhdr, 0xffffffffl); case 2: return GC_block_nearly_full1(hhdr, 0x55555555l); case 4: return GC_block_nearly_full1(hhdr, 0x11111111l); case 6: return GC_block_nearly_full3(hhdr, 0x41041041l, 0x10410410l, 0x04104104l); case 8: return GC_block_nearly_full1(hhdr, 0x01010101l); case 12: return GC_block_nearly_full3(hhdr, 0x01001001l, 0x10010010l, 0x00100100l); case 16: return GC_block_nearly_full1(hhdr, 0x00010001l); case 32: return GC_block_nearly_full1(hhdr, 0x00000001l); default: return DONT_KNOW; } # endif # if CPP_WORDSZ == 64 switch(sz) { case 1: return GC_block_nearly_full1(hhdr, 0xffffffffffffffffl); case 2: return GC_block_nearly_full1(hhdr, 0x5555555555555555l); case 4: return GC_block_nearly_full1(hhdr, 0x1111111111111111l); case 6: return GC_block_nearly_full3(hhdr, 0x1041041041041041l, 0x4104104104104104l, 0x0410410410410410l); case 8: return GC_block_nearly_full1(hhdr, 0x0101010101010101l); case 12: return GC_block_nearly_full3(hhdr, 0x1001001001001001l, 0x0100100100100100l, 0x0010010010010010l); case 16: return GC_block_nearly_full1(hhdr, 0x0001000100010001l); case 32: return GC_block_nearly_full1(hhdr, 0x0000000100000001l); default: return DONT_KNOW; } # endif } #endif /* !SMALL_CONFIG && !USE_MARK_BYTES */ /* We keep track of reclaimed memory if we are either asked to, or */ /* we are using the parallel marker. In the latter case, we assume */ /* that most allocation goes through GC_malloc_many for scalability. */ /* GC_malloc_many needs the count anyway. */ # if defined(GATHERSTATS) || defined(PARALLEL_MARK) # define INCR_WORDS(sz) n_words_found += (sz) # define COUNT_PARAM , count # define COUNT_ARG , count # define COUNT_DECL signed_word * count; # define NWORDS_DECL signed_word n_words_found = 0; # define COUNT_UPDATE *count += n_words_found; # define MEM_FOUND_ADDR , &GC_mem_found # else # define INCR_WORDS(sz) # define COUNT_PARAM # define COUNT_ARG # define COUNT_DECL # define NWORDS_DECL # define COUNT_UPDATE # define MEM_FOUND_ADDR # endif /* * Restore unmarked small objects in h of size sz to the object * free list. Returns the new list. * Clears unmarked objects. */ /*ARGSUSED*/ ptr_t GC_reclaim_clear(hbp, hhdr, sz, list COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ register hdr * hhdr; register ptr_t list; register word sz; COUNT_DECL { register int word_no; register word *p, *q, *plim; NWORDS_DECL GC_ASSERT(hhdr == GC_find_header((ptr_t)hbp)); p = (word *)(hbp->hb_body); word_no = 0; plim = (word *)((((word)hbp) + HBLKSIZE) - WORDS_TO_BYTES(sz)); /* go through all words in block */ while( p <= plim ) { if( mark_bit_from_hdr(hhdr, word_no) ) { p += sz; } else { INCR_WORDS(sz); /* object is available - put on list */ obj_link(p) = list; list = ((ptr_t)p); /* Clear object, advance p to next object in the process */ q = p + sz; # ifdef USE_MARK_BYTES GC_ASSERT(!(sz & 1) && !((word)p & (2 * sizeof(word) - 1))); p[1] = 0; p += 2; while (p < q) { CLEAR_DOUBLE(p); p += 2; } # else p++; /* Skip link field */ while (p < q) { *p++ = 0; } # endif } word_no += sz; } COUNT_UPDATE return(list); } #if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES) /* * A special case for 2 word composite objects (e.g. cons cells): */ /*ARGSUSED*/ ptr_t GC_reclaim_clear2(hbp, hhdr, list COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ hdr * hhdr; register ptr_t list; COUNT_DECL { register word * mark_word_addr = &(hhdr->hb_marks[0]); register word *p, *plim; register word mark_word; register int i; NWORDS_DECL # define DO_OBJ(start_displ) \ if (!(mark_word & ((word)1 << start_displ))) { \ p[start_displ] = (word)list; \ list = (ptr_t)(p+start_displ); \ p[start_displ+1] = 0; \ INCR_WORDS(2); \ } p = (word *)(hbp->hb_body); plim = (word *)(((word)hbp) + HBLKSIZE); /* go through all words in block */ while( p < plim ) { mark_word = *mark_word_addr++; for (i = 0; i < WORDSZ; i += 8) { DO_OBJ(0); DO_OBJ(2); DO_OBJ(4); DO_OBJ(6); p += 8; mark_word >>= 8; } } COUNT_UPDATE return(list); # undef DO_OBJ } /* * Another special case for 4 word composite objects: */ /*ARGSUSED*/ ptr_t GC_reclaim_clear4(hbp, hhdr, list COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ hdr * hhdr; register ptr_t list; COUNT_DECL { register word * mark_word_addr = &(hhdr->hb_marks[0]); register word *p, *plim; register word mark_word; NWORDS_DECL # define DO_OBJ(start_displ) \ if (!(mark_word & ((word)1 << start_displ))) { \ p[start_displ] = (word)list; \ list = (ptr_t)(p+start_displ); \ p[start_displ+1] = 0; \ CLEAR_DOUBLE(p + start_displ + 2); \ INCR_WORDS(4); \ } p = (word *)(hbp->hb_body); plim = (word *)(((word)hbp) + HBLKSIZE); /* go through all words in block */ while( p < plim ) { mark_word = *mark_word_addr++; DO_OBJ(0); DO_OBJ(4); DO_OBJ(8); DO_OBJ(12); DO_OBJ(16); DO_OBJ(20); DO_OBJ(24); DO_OBJ(28); # if CPP_WORDSZ == 64 DO_OBJ(32); DO_OBJ(36); DO_OBJ(40); DO_OBJ(44); DO_OBJ(48); DO_OBJ(52); DO_OBJ(56); DO_OBJ(60); # endif p += WORDSZ; } COUNT_UPDATE return(list); # undef DO_OBJ } #endif /* !SMALL_CONFIG && !USE_MARK_BYTES */ /* The same thing, but don't clear objects: */ /*ARGSUSED*/ ptr_t GC_reclaim_uninit(hbp, hhdr, sz, list COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ register hdr * hhdr; register ptr_t list; register word sz; COUNT_DECL { register int word_no = 0; register word *p, *plim; NWORDS_DECL p = (word *)(hbp->hb_body); plim = (word *)((((word)hbp) + HBLKSIZE) - WORDS_TO_BYTES(sz)); /* go through all words in block */ while( p <= plim ) { if( !mark_bit_from_hdr(hhdr, word_no) ) { INCR_WORDS(sz); /* object is available - put on list */ obj_link(p) = list; list = ((ptr_t)p); } p += sz; word_no += sz; } COUNT_UPDATE return(list); } /* Don't really reclaim objects, just check for unmarked ones: */ /*ARGSUSED*/ void GC_reclaim_check(hbp, hhdr, sz) register struct hblk *hbp; /* ptr to current heap block */ register hdr * hhdr; register word sz; { register int word_no = 0; register word *p, *plim; # ifdef GATHERSTATS register int n_words_found = 0; # endif p = (word *)(hbp->hb_body); plim = (word *)((((word)hbp) + HBLKSIZE) - WORDS_TO_BYTES(sz)); /* go through all words in block */ while( p <= plim ) { if( !mark_bit_from_hdr(hhdr, word_no) ) { FOUND_FREE(hbp, word_no); } p += sz; word_no += sz; } } #if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES) /* * Another special case for 2 word atomic objects: */ /*ARGSUSED*/ ptr_t GC_reclaim_uninit2(hbp, hhdr, list COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ hdr * hhdr; register ptr_t list; COUNT_DECL { register word * mark_word_addr = &(hhdr->hb_marks[0]); register word *p, *plim; register word mark_word; register int i; NWORDS_DECL # define DO_OBJ(start_displ) \ if (!(mark_word & ((word)1 << start_displ))) { \ p[start_displ] = (word)list; \ list = (ptr_t)(p+start_displ); \ INCR_WORDS(2); \ } p = (word *)(hbp->hb_body); plim = (word *)(((word)hbp) + HBLKSIZE); /* go through all words in block */ while( p < plim ) { mark_word = *mark_word_addr++; for (i = 0; i < WORDSZ; i += 8) { DO_OBJ(0); DO_OBJ(2); DO_OBJ(4); DO_OBJ(6); p += 8; mark_word >>= 8; } } COUNT_UPDATE return(list); # undef DO_OBJ } /* * Another special case for 4 word atomic objects: */ /*ARGSUSED*/ ptr_t GC_reclaim_uninit4(hbp, hhdr, list COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ hdr * hhdr; register ptr_t list; COUNT_DECL { register word * mark_word_addr = &(hhdr->hb_marks[0]); register word *p, *plim; register word mark_word; NWORDS_DECL # define DO_OBJ(start_displ) \ if (!(mark_word & ((word)1 << start_displ))) { \ p[start_displ] = (word)list; \ list = (ptr_t)(p+start_displ); \ INCR_WORDS(4); \ } p = (word *)(hbp->hb_body); plim = (word *)(((word)hbp) + HBLKSIZE); /* go through all words in block */ while( p < plim ) { mark_word = *mark_word_addr++; DO_OBJ(0); DO_OBJ(4); DO_OBJ(8); DO_OBJ(12); DO_OBJ(16); DO_OBJ(20); DO_OBJ(24); DO_OBJ(28); # if CPP_WORDSZ == 64 DO_OBJ(32); DO_OBJ(36); DO_OBJ(40); DO_OBJ(44); DO_OBJ(48); DO_OBJ(52); DO_OBJ(56); DO_OBJ(60); # endif p += WORDSZ; } COUNT_UPDATE return(list); # undef DO_OBJ } /* Finally the one word case, which never requires any clearing: */ /*ARGSUSED*/ ptr_t GC_reclaim1(hbp, hhdr, list COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ hdr * hhdr; register ptr_t list; COUNT_DECL { register word * mark_word_addr = &(hhdr->hb_marks[0]); register word *p, *plim; register word mark_word; register int i; NWORDS_DECL # define DO_OBJ(start_displ) \ if (!(mark_word & ((word)1 << start_displ))) { \ p[start_displ] = (word)list; \ list = (ptr_t)(p+start_displ); \ INCR_WORDS(1); \ } p = (word *)(hbp->hb_body); plim = (word *)(((word)hbp) + HBLKSIZE); /* go through all words in block */ while( p < plim ) { mark_word = *mark_word_addr++; for (i = 0; i < WORDSZ; i += 4) { DO_OBJ(0); DO_OBJ(1); DO_OBJ(2); DO_OBJ(3); p += 4; mark_word >>= 4; } } COUNT_UPDATE return(list); # undef DO_OBJ } #endif /* !SMALL_CONFIG && !USE_MARK_BYTES */ /* * Generic procedure to rebuild a free list in hbp. * Also called directly from GC_malloc_many. */ ptr_t GC_reclaim_generic(hbp, hhdr, sz, init, list COUNT_PARAM) struct hblk *hbp; /* ptr to current heap block */ hdr * hhdr; GC_bool init; ptr_t list; word sz; COUNT_DECL { ptr_t result = list; GC_ASSERT(GC_find_header((ptr_t)hbp) == hhdr); GC_remove_protection(hbp, 1, (hhdr)->hb_descr == 0 /* Pointer-free? */); if (init) { switch(sz) { # if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES) case 1: /* We now issue the hint even if GC_nearly_full returned */ /* DONT_KNOW. */ result = GC_reclaim1(hbp, hhdr, list COUNT_ARG); break; case 2: result = GC_reclaim_clear2(hbp, hhdr, list COUNT_ARG); break; case 4: result = GC_reclaim_clear4(hbp, hhdr, list COUNT_ARG); break; # endif /* !SMALL_CONFIG && !USE_MARK_BYTES */ default: result = GC_reclaim_clear(hbp, hhdr, sz, list COUNT_ARG); break; } } else { GC_ASSERT((hhdr)->hb_descr == 0 /* Pointer-free block */); switch(sz) { # if !defined(SMALL_CONFIG) && !defined(USE_MARK_BYTES) case 1: result = GC_reclaim1(hbp, hhdr, list COUNT_ARG); break; case 2: result = GC_reclaim_uninit2(hbp, hhdr, list COUNT_ARG); break; case 4: result = GC_reclaim_uninit4(hbp, hhdr, list COUNT_ARG); break; # endif /* !SMALL_CONFIG && !USE_MARK_BYTES */ default: result = GC_reclaim_uninit(hbp, hhdr, sz, list COUNT_ARG); break; } } if (IS_UNCOLLECTABLE(hhdr -> hb_obj_kind)) GC_set_hdr_marks(hhdr); return result; } /* * Restore unmarked small objects in the block pointed to by hbp * to the appropriate object free list. * If entirely empty blocks are to be completely deallocated, then * caller should perform that check. */ void GC_reclaim_small_nonempty_block(hbp, report_if_found COUNT_PARAM) register struct hblk *hbp; /* ptr to current heap block */ int report_if_found; /* Abort if a reclaimable object is found */ COUNT_DECL { hdr *hhdr = HDR(hbp); word sz = hhdr -> hb_sz; int kind = hhdr -> hb_obj_kind; struct obj_kind * ok = &GC_obj_kinds[kind]; ptr_t * flh = &(ok -> ok_freelist[sz]); hhdr -> hb_last_reclaimed = (unsigned short) GC_gc_no; if (report_if_found) { GC_reclaim_check(hbp, hhdr, sz); } else { *flh = GC_reclaim_generic(hbp, hhdr, sz, (ok -> ok_init || GC_debugging_started), *flh MEM_FOUND_ADDR); } } /* * Restore an unmarked large object or an entirely empty blocks of small objects * to the heap block free list. * Otherwise enqueue the block for later processing * by GC_reclaim_small_nonempty_block. * If report_if_found is TRUE, then process any block immediately, and * simply report free objects; do not actually reclaim them. */ # if defined(__STDC__) || defined(__cplusplus) void GC_reclaim_block(register struct hblk *hbp, word report_if_found) # else void GC_reclaim_block(hbp, report_if_found) register struct hblk *hbp; /* ptr to current heap block */ word report_if_found; /* Abort if a reclaimable object is found */ # endif { register hdr * hhdr; register word sz; /* size of objects in current block */ register struct obj_kind * ok; struct hblk ** rlh; hhdr = HDR(hbp); sz = hhdr -> hb_sz; ok = &GC_obj_kinds[hhdr -> hb_obj_kind]; if( sz > MAXOBJSZ ) { /* 1 big object */ if( !mark_bit_from_hdr(hhdr, 0) ) { if (report_if_found) { FOUND_FREE(hbp, 0); } else { word blocks = OBJ_SZ_TO_BLOCKS(sz); if (blocks > 1) { GC_large_allocd_bytes -= blocks * HBLKSIZE; } # ifdef GATHERSTATS GC_mem_found += sz; # endif GC_freehblk(hbp); } } } else { GC_bool empty = GC_block_empty(hhdr); if (report_if_found) { GC_reclaim_small_nonempty_block(hbp, (int)report_if_found MEM_FOUND_ADDR); } else if (empty) { # ifdef GATHERSTATS GC_mem_found += BYTES_TO_WORDS(HBLKSIZE); # endif GC_freehblk(hbp); } else if (TRUE != GC_block_nearly_full(hhdr)){ /* group of smaller objects, enqueue the real work */ rlh = &(ok -> ok_reclaim_list[sz]); hhdr -> hb_next = *rlh; *rlh = hbp; } /* else not worth salvaging. */ /* We used to do the nearly_full check later, but we */ /* already have the right cache context here. Also */ /* doing it here avoids some silly lock contention in */ /* GC_malloc_many. */ } } #if !defined(NO_DEBUGGING) /* Routines to gather and print heap block info */ /* intended for debugging. Otherwise should be called */ /* with lock. */ struct Print_stats { size_t number_of_blocks; size_t total_bytes; }; #ifdef USE_MARK_BYTES /* Return the number of set mark bits in the given header */ int GC_n_set_marks(hhdr) hdr * hhdr; { register int result = 0; register int i; for (i = 0; i < MARK_BITS_SZ; i++) { result += hhdr -> hb_marks[i]; } return(result); } #else /* Number of set bits in a word. Not performance critical. */ static int set_bits(n) word n; { register word m = n; register int result = 0; while (m > 0) { if (m & 1) result++; m >>= 1; } return(result); } /* Return the number of set mark bits in the given header */ int GC_n_set_marks(hhdr) hdr * hhdr; { register int result = 0; register int i; for (i = 0; i < MARK_BITS_SZ; i++) { result += set_bits(hhdr -> hb_marks[i]); } return(result); } #endif /* !USE_MARK_BYTES */ /*ARGSUSED*/ # if defined(__STDC__) || defined(__cplusplus) void GC_print_block_descr(struct hblk *h, word dummy) # else void GC_print_block_descr(h, dummy) struct hblk *h; word dummy; # endif { register hdr * hhdr = HDR(h); register size_t bytes = WORDS_TO_BYTES(hhdr -> hb_sz); struct Print_stats *ps; GC_printf3("(%lu:%lu,%lu)", (unsigned long)(hhdr -> hb_obj_kind), (unsigned long)bytes, (unsigned long)(GC_n_set_marks(hhdr))); bytes += HBLKSIZE-1; bytes &= ~(HBLKSIZE-1); ps = (struct Print_stats *)dummy; ps->total_bytes += bytes; ps->number_of_blocks++; } void GC_print_block_list() { struct Print_stats pstats; GC_printf1("(kind(0=ptrfree,1=normal,2=unc.,%lu=stubborn):size_in_bytes, #_marks_set)\n", STUBBORN); pstats.number_of_blocks = 0; pstats.total_bytes = 0; GC_apply_to_all_blocks(GC_print_block_descr, (word)&pstats); GC_printf2("\nblocks = %lu, bytes = %lu\n", (unsigned long)pstats.number_of_blocks, (unsigned long)pstats.total_bytes); } #endif /* NO_DEBUGGING */ /* * Clear all obj_link pointers in the list of free objects *flp. * Clear *flp. * This must be done before dropping a list of free gcj-style objects, * since may otherwise end up with dangling "descriptor" pointers. * It may help for other pointer-containing objects. */ void GC_clear_fl_links(flp) ptr_t *flp; { ptr_t next = *flp; while (0 != next) { *flp = 0; flp = &(obj_link(next)); next = *flp; } } /* * Perform GC_reclaim_block on the entire heap, after first clearing * small object free lists (if we are not just looking for leaks). */ void GC_start_reclaim(report_if_found) int report_if_found; /* Abort if a GC_reclaimable object is found */ { int kind; # if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC) GC_ASSERT(0 == GC_fl_builder_count); # endif /* Clear reclaim- and free-lists */ for (kind = 0; kind < GC_n_kinds; kind++) { ptr_t *fop; ptr_t *lim; struct hblk ** rlp; struct hblk ** rlim; struct hblk ** rlist = GC_obj_kinds[kind].ok_reclaim_list; GC_bool should_clobber = (GC_obj_kinds[kind].ok_descriptor != 0); if (rlist == 0) continue; /* This kind not used. */ if (!report_if_found) { lim = &(GC_obj_kinds[kind].ok_freelist[MAXOBJSZ+1]); for( fop = GC_obj_kinds[kind].ok_freelist; fop < lim; fop++ ) { if (*fop != 0) { if (should_clobber) { GC_clear_fl_links(fop); } else { *fop = 0; } } } } /* otherwise free list objects are marked, */ /* and its safe to leave them */ rlim = rlist + MAXOBJSZ+1; for( rlp = rlist; rlp < rlim; rlp++ ) { *rlp = 0; } } # ifdef PRINTBLOCKS GC_printf0("GC_reclaim: current block sizes:\n"); GC_print_block_list(); # endif /* Go through all heap blocks (in hblklist) and reclaim unmarked objects */ /* or enqueue the block for later processing. */ GC_apply_to_all_blocks(GC_reclaim_block, (word)report_if_found); # ifdef EAGER_SWEEP /* This is a very stupid thing to do. We make it possible anyway, */ /* so that you can convince yourself that it really is very stupid. */ GC_reclaim_all((GC_stop_func)0, FALSE); # endif # if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC) GC_ASSERT(0 == GC_fl_builder_count); # endif } /* * Sweep blocks of the indicated object size and kind until either the * appropriate free list is nonempty, or there are no more blocks to * sweep. */ void GC_continue_reclaim(sz, kind) word sz; /* words */ int kind; { register hdr * hhdr; register struct hblk * hbp; register struct obj_kind * ok = &(GC_obj_kinds[kind]); struct hblk ** rlh = ok -> ok_reclaim_list; ptr_t *flh = &(ok -> ok_freelist[sz]); if (rlh == 0) return; /* No blocks of this kind. */ rlh += sz; while ((hbp = *rlh) != 0) { hhdr = HDR(hbp); *rlh = hhdr -> hb_next; GC_reclaim_small_nonempty_block(hbp, FALSE MEM_FOUND_ADDR); if (*flh != 0) break; } } /* * Reclaim all small blocks waiting to be reclaimed. * Abort and return FALSE when/if (*stop_func)() returns TRUE. * If this returns TRUE, then it's safe to restart the world * with incorrectly cleared mark bits. * If ignore_old is TRUE, then reclaim only blocks that have been * recently reclaimed, and discard the rest. * Stop_func may be 0. */ GC_bool GC_reclaim_all(stop_func, ignore_old) GC_stop_func stop_func; GC_bool ignore_old; { register word sz; register int kind; register hdr * hhdr; register struct hblk * hbp; register struct obj_kind * ok; struct hblk ** rlp; struct hblk ** rlh; # ifdef PRINTTIMES CLOCK_TYPE start_time; CLOCK_TYPE done_time; GET_TIME(start_time); # endif for (kind = 0; kind < GC_n_kinds; kind++) { ok = &(GC_obj_kinds[kind]); rlp = ok -> ok_reclaim_list; if (rlp == 0) continue; for (sz = 1; sz <= MAXOBJSZ; sz++) { rlh = rlp + sz; while ((hbp = *rlh) != 0) { if (stop_func != (GC_stop_func)0 && (*stop_func)()) { return(FALSE); } hhdr = HDR(hbp); *rlh = hhdr -> hb_next; if (!ignore_old || hhdr -> hb_last_reclaimed == GC_gc_no - 1) { /* It's likely we'll need it this time, too */ /* It's been touched recently, so this */ /* shouldn't trigger paging. */ GC_reclaim_small_nonempty_block(hbp, FALSE MEM_FOUND_ADDR); } } } } # ifdef PRINTTIMES GET_TIME(done_time); GC_printf1("Disposing of reclaim lists took %lu msecs\n", MS_TIME_DIFF(done_time,start_time)); # endif return(TRUE); }
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