pike.git/src/gc.c:6175593b8a88181e4cb41c91c56a9805798f8f18

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5622 5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658 5659 5660 5661 5662 5663 5664 5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 /* || This file is part of Pike. For copyright information see COPYRIGHT. || Pike is distributed under GPL, LGPL and MPL. See the file COPYING || for more information. || $Id: gc.c,v 1.331 2008/10/12 22:41:16 mast Exp $ */ #include "global.h" struct callback *gc_evaluator_callback=0; #include "array.h" #include "multiset.h" #include "mapping.h" #include "object.h" #include "program.h" #include "stralloc.h" #include "stuff.h" #include "pike_error.h" #include "pike_memory.h" #include "pike_macros.h" #include "pike_rusage.h" #include "pike_types.h" #include "time_stuff.h" #include "constants.h" #include "interpret.h" #include "bignum.h" #include "pike_threadlib.h" #include "gc.h" #include "main.h" #include <math.h> #include <assert.h> #include "block_alloc.h" int gc_enabled = 1; /* These defaults are only guesses and hardly tested at all. Please improve. */ double gc_garbage_ratio_low = 0.2; double gc_time_ratio = 0.05; double gc_garbage_ratio_high = 0.5; /* This slowness factor approximately corresponds to the average over * the last ten gc rounds. (0.9 == 1 - 1/10) */ double gc_average_slowness = 0.9; /* The gc will free all things with no external nonweak references * that isn't referenced by live objects. An object is considered * "live" if it contains code that must be executed when it is * destructed; see gc_object_is_live for details. Live objects without * external references are then destructed and garbage collected with * normal refcount garbing (which might leave dead garbage around for * the next gc). These live objects are destructed in an order that * tries to be as well defined as possible using several rules: * * o If an object A references B single way, then A is destructed * before B. * o If A and B are in a cycle, and there is a reference somewhere * from B to A that is weaker than any reference from A to B, then * the cycle is resolved by disregarding the weaker reference, and * A is therefore destructed before B. * o If a cycle is resolved through disregarding a weaker reference * according to the preceding rule, and there is another cycle * without weak references which also gets resolved through * disregarding the same reference, then the other cycle won't be * resolved by disregarding some other reference. * o Weak references are considered weaker than normal ones, and both * are considered weaker than strong references. * o Strong references are used in special cases like parent object * references. There can never be a cycle consisting only of strong * references. (This means the gc will never destruct a parent * object before all children have been destructed.) * * The gc tries to detect and warn about cases where there are live * objects with no well defined order between them. There are cases * that are missed by this detection, though. * * Things that aren't live objects but are referenced from them are * still intact during this destruct pass, so it's entirely possible * to save them by adding external references to them. However, it's * not possible for live objects to save themselves or other live * objects; all live objects that didn't have external references at * the start of the gc pass will be destructed regardless of added * references. * * Things that have only weak external references at the start of the * gc pass will be freed. That's done before the live object destruct * pass. Internal weak references are however still intact. * * Note: Keep the doc for lfun::destroy up-to-date with the above. */ /* #define GC_VERBOSE */ /* #define GC_CYCLE_DEBUG */ /* #define GC_STACK_DEBUG */ #if defined(GC_VERBOSE) && !defined(PIKE_DEBUG) #undef GC_VERBOSE #endif #ifdef GC_VERBOSE #define GC_VERBOSE_DO(X) X #else #define GC_VERBOSE_DO(X) #endif int num_objects = 2; /* Account for *_empty_array. */ int got_unlinked_things; ALLOC_COUNT_TYPE num_allocs =0; ALLOC_COUNT_TYPE alloc_threshold = GC_MIN_ALLOC_THRESHOLD; PMOD_EXPORT int Pike_in_gc = 0; int gc_generation = 0; time_t last_gc; int gc_trace = 0, gc_debug = 0; #ifdef DO_PIKE_CLEANUP int gc_destruct_everything = 0; #endif size_t gc_ext_weak_refs; static double objects_alloced = 0.0; static double objects_freed = 0.0; static double gc_time = 0.0, non_gc_time = 0.0; static cpu_time_t last_gc_end_time = 0; #ifdef CPU_TIME_MIGHT_NOT_BE_THREAD_LOCAL cpu_time_t auto_gc_time = 0; #endif struct link_frame /* See cycle checking blurb below. */ { void *data; struct link_frame *prev; /* Previous frame in the link stack. */ gc_cycle_check_cb *checkfn; /* Function to call to recurse the thing. */ int weak; /* Weak flag to checkfn. */ }; struct gc_rec_frame /* See cycle checking blurb below. */ { void *data; int rf_flags; struct gc_rec_frame *prev; /* The previous frame in the recursion stack. * NULL for frames not in the stack (i.e. on a * cycle piece list or in the kill list). */ struct gc_rec_frame *next; /* The next frame in the recursion stack or the * kill list. Undefined for frames on cycle * piece lists. */ struct gc_rec_frame *cycle_id;/* For a frame in the recursion stack: The * cycle identifier frame. * For a frame on a cycle piece list: The frame * in the recursion stack whose cycle piece * list this frame is in. */ struct gc_rec_frame *cycle_piece;/* The start of the cycle piece list for * frames on the recursion stack, or the next * frame in the list for frames in cycle piece * lists. */ union { struct link_frame *link_top;/* The top of the link stack for frames on the * recursion stack. */ struct gc_rec_frame *last_cycle_piece;/* In the first frame on a cycle * piece list, this is used to point to the * last frame in the list. */ } u; }; /* rf_flags bits. */ #define GC_PREV_WEAK 0x0001 #define GC_PREV_STRONG 0x0002 #define GC_PREV_BROKEN 0x0004 #define GC_MARK_LIVE 0x0008 #define GC_ON_KILL_LIST 0x0010 #ifdef PIKE_DEBUG #define GC_ON_CYCLE_PIECE_LIST 0x0020 #define GC_FRAME_FREED 0x0040 #define GC_FOLLOWED_NONSTRONG 0x0080 #define GC_IS_VALID_CP_CYCLE_ID 0x0100 #endif static struct gc_rec_frame sentinel_frame = { (void *) (ptrdiff_t) -1, 0, (struct gc_rec_frame *) (ptrdiff_t) -1, (struct gc_rec_frame *) (ptrdiff_t) -1, &sentinel_frame, /* Recognize as cycle id frame. */ (struct gc_rec_frame *) (ptrdiff_t) -1, {(struct link_frame *) (ptrdiff_t) -1} }; static struct gc_rec_frame *stack_top = &sentinel_frame; static struct gc_rec_frame *kill_list = &sentinel_frame; /* Cycle checking * * When a thing is recursed into, a gc_rec_frame is pushed onto the * recursion stack whose top pointer is stack_top. After that the * links emanating from that thing are collected through the * gc_cycle_check_* functions and pushed as link_frames onto a link * stack that is specific to the rec frame. gc_rec_frame.u.link_top is * the top pointer of that stack. The link frames are then popped off * again one by one. If the thing that the link points to hasn't been * visited already then it's recursed, which means that the link frame * is popped off the link stack and a new rec frame is pushed onto the * main stack instead. * * When a reference is followed to a thing which has a rec frame * (either on the stack or on a cycle piece list - see below), we have * a cycle. However, if that reference is weak (or becomes weak after * rotation - see below), it's still not regarded as a cycle since * weak refs always are eligible to be broken to resolve cycles. * * A sequence of frames on the recursion stack forms a cycle iff they * have the same value in gc_rec_frame.cycle_id. A cycle is always * continuous on the stack. * * Furthermore, the cycle_ids always point to the first (deepest) * frame on the stack that is part of the cycle. That frame is called * the "cycle identifier frame" since all frames in the cycle will end * up there if the cycle pointers are followed transitively. The * cycle_id pointer in the cycle identifier frame points to itself. * Every frame is initially treated as a cycle containing only itself. * * When the recursion leaves a thing, the rec frame is popped off the * stack. If the frame is part of a cycle that isn't finished at that * point, it's not freed but instead linked onto the cycle piece list * in gc_rec_frame.cycle_piece of the parent rec frame (which * necessarily is part of the same cycle). That is done to detect * cyclic refs that end up at the popped frame later on. * * The cycle_id pointers for frames on cycle piece lists point back * towards the rec frame that still is on the stack, but not past it * to the cycle id frame (which might be further back in the stack). * Whenever cycle_id pointer chains are traversed to find the root of * a cycle piece list, they are compacted to avoid O(n) complexity. * * The current tentative destruct order is described by the order on * the stack and the attached cycle piece lists: The thing that's * deepest in the stack is destructed first and the recursion stack * has precedence over the cycle piece list (the reason for that is * explained later). To illustrate: * ,- stack_top * v * t1 <=> t2 <=> ... <=> t3 * | | `-> t4 -> ... -> t5 * | `-> t6 -> ... -> t7 * `-> t8 -> ... -> t9 * * Here <=> represents links on the recursion stack and -> links in * the cycle piece lists. The tentative destruct order for these * things is the same as the numbering above. * * Since we strive to keep the refs intact during destruction, the * above means that the refs which have priority to be kept intact * should point towards the top of the stack and towards the end of * the cycle piece lists. * * To allow rotations, the recursion stack is a double linked list * using gc_rec_frame.prev and gc_rec_frame.next. Rotations are the * operation used to manipulate the order to avoid getting a * prioritized link pointing in the wrong direction: * ,- stack_top * weak v * t1 <=> ... <=> t2 <=> ... <=> t3 <-> t4 <=> ... <=> t5 * * If a nonweak backward pointer from t5 to t2 is encountered here, we * should prefer to break(*) the weak ref between t3 and t4. The stack * is therefore rotated to become: * ,- stack_top * broken v * t1 <=> ... <#> t4 <=> ... <=> t5 <=> t2 <=> ... <=> t3 * * The section to rotate always ends at the top of the stack. * * The strength of the refs along the stack links are represented as * follows: * * o Things with a strong ref between them are kept next to each * other, and the second (the one being referenced by the strong * ref) has the GC_PREV_STRONG bit set. A rotation never breaks the * list inside a sequence of strong refs. * * o The GC_PREV_WEAK bit is set in the next frame for every link on * the stack where no preceding frame reference any following frame * with anything but weak refs. * * o GC_PREV_BROKEN is set in frames that are rotated back, i.e. t4 * in the example above. This is used to break later cycles in the * same position when they can't be broken at a weak link. * * If a nonweak backward pointer is found and there are no weak refs * on the stack to break at, the section from the top of the stack * down to the thing referenced by the backward pointer is marked up * as a cycle (possibly extending the cycle which that thing already * belongs to). Therefore weak refs never occur inside cycles. * * Several separate cycles may be present on the stack simultaneously. * That happens when a subcycle which is referenced one way from an * earlier cycle is encountered. E.g. * * L--. L--. * t1 t2 -> t3 t4 * `--7 `--7 * * where the visit order is t1, t2, t3 and then t4. Because of the * stack which causes a subcycle to always be added to the top, it can * be handled independently of the earlier cycles, and those earlier * cycles can also be extended later on when the subcycle has been * popped off. If a ref from the subcycle to an earlier cycle is * found, that means that both are really the same cycle, and the * frames in the former subcycle will instead become a cycle piece * list on a frame in the former preceding cycle. * * Cycles are always kept continuous on the recursion stack. Since * breaking a weak ref doesn't mark up a cycle, it's necessary to * rotate between whole cycles when a weak ref is broken. I.e: * * weak * ... <=> t1a <=> t1b <=> t1c <=> ... <=> t2 <-> t3 <=> ... <=> t4 * * Here all the t1 things are members of a cycle, with t1a being the * first and t1c the last. Let's say a nonweak pointer is found from * t4 to t1b, and the weak link between t2 and t3 is chosen to be * broken. In this case the whole t1 cycle is rotated up: * * broken * ... <#> t3 <=> ... <=> t4 <=> t1a <=> t1b <=> t1c <=> ... <=> t2 * * This way the t1 cycle can continue to be processed independently * and possibly be popped off separately from the segment between t3 * and t4. * * Since the link frames are kept in substacks attached to the rec * frames, they get rotated with the rec frames. This has the effect * that the links from the top rec frame on the stack always are * tested first. That is necessary to avoid clobbering weak ref * partitions. Example: * * weak weak * t1 <=> t2 <-> t3 <=> t4 <-> t5 * * A nonweak ref is found from t5 to t2. We get this after rotation * (assuming t1 and t2 aren't part of the same cycle): * * broken weak * t1 <#> t5 <=> t2 <-> t3 <=> t4 * * Now, if we would continue to follow the links from t5 and encounter * a new thing t7, we'd have to add it to the top. If that ref isn't * weak we'd have to blank out the weak flag which could be used in * other rotations above t5 (e.g. if a normal ref from t4 to t2 is * encountered). To avoid this we do the t4 links instead and continue * with t5 when t4, t3 and t2 are done. * * As said earlier, rec frames are moved to cycle piece lists when * they are popped off while being part of unfinished cycles. Since * there are no more outgoing refs at that point, there can be no more * rotations that affect the order between the rec frame and its * predecessor. Therefore the order on a cycle piece list is optimal * (in as far as the gc destruct order policy goes). Any further * rotations can move the predecessor around, but it can always be * treated as one unit together with its cycle piece list. * * If the preceding frame already has a cycle piece list when a rec * frame should be added to it, the rec frame (and its attached cycle * piece list) is linked in before that list. That since the rec frame * might have refs to the earlier cycle piece list, but the opposite * can't happen. * * When a cycle identifier frame is popped off the stack, the frame * together with its cycle piece list represent the complete cycle, * and the list holds an optimal order for destructing it. The frames * are freed at that point, except for the ones which correspond to * live objects, which instead are linked in order into the beginning * of the kill list. That list, whose beginning is pointed to by * kill_list, holds the final destruct order for all live objects. * * Note that the complete cycle has to be added to the kill list at * once since all live objects that are referenced single way from the * cycle should be destructed later and must therefore be put on the * kill list before the cycle. * * The cycle check functions might recurse another round through the * frames that have been recursed already, to propagate the GC_LIVE * flag to things that have been found to be referenced from live * objects. In this mode a single dummy rec frame with the * GC_MARK_LIVE bit is pushed on the recursion stack, and all link * frames are stacked in it, regardless of the things they originate * from. Nothing else happens while this is done, i.e. no rotations * and so forth, so the dummy frame always stays at the top until it's * removed again. * * *) Here "breaking" a ref doesn't mean that it actually gets * zeroed out. It's only disregarded to resolve the cycle to * produce an optimal destruct order. I.e. it will still be intact * when the first object in the cycle is destructed, and it will * only be zeroed when the thing it points to has been destructed. */ /* The free extra list. See note in gc_delayed_free. */ struct free_extra_frame { void *data; struct free_extra_frame *next; /* Next pointer. */ int type; /* The type of the thing. */ }; static struct free_extra_frame *free_extra_list = NULL; #ifdef PIKE_DEBUG static unsigned delayed_freed, weak_freed, checked, marked, cycle_checked, live_ref; static unsigned mark_live, frame_rot, link_search; static unsigned gc_extra_refs = 0; static unsigned tot_cycle_checked = 0, tot_mark_live = 0, tot_frame_rot = 0; static unsigned gc_rec_frame_seq_max; #endif static unsigned rec_frames, link_frames, free_extra_frames; static unsigned max_rec_frames, max_link_frames; static unsigned tot_max_rec_frames = 0, tot_max_link_frames = 0, tot_max_free_extra_frames = 0; #undef INIT_BLOCK #define INIT_BLOCK(f) do { \ if (++rec_frames > max_rec_frames) \ max_rec_frames = rec_frames; \ } while (0) #undef EXIT_BLOCK #define EXIT_BLOCK(f) do { \ DO_IF_DEBUG ({ \ if (f->rf_flags & GC_FRAME_FREED) \ gc_fatal (f->data, 0, "Freeing gc_rec_frame twice.\n"); \ f->rf_flags |= GC_FRAME_FREED; \ f->u.link_top = (struct link_frame *) (ptrdiff_t) -1; \ f->prev = f->next = f->cycle_id = f->cycle_piece = \ (struct gc_rec_frame *) (ptrdiff_t) -1; \ }); \ rec_frames--; \ } while (0) BLOCK_ALLOC_FILL_PAGES (gc_rec_frame, 2) /* Link and free_extra frames are approximately the same size, so let * them share block_alloc area. */ struct ba_mixed_frame { union { struct link_frame link; struct free_extra_frame free_extra; struct ba_mixed_frame *next; /* For block_alloc internals. */ } u; }; #undef BLOCK_ALLOC_NEXT #define BLOCK_ALLOC_NEXT u.next #undef INIT_BLOCK #define INIT_BLOCK(f) #undef EXIT_BLOCK #define EXIT_BLOCK(f) BLOCK_ALLOC_FILL_PAGES (ba_mixed_frame, 2) static INLINE struct link_frame *alloc_link_frame() { struct ba_mixed_frame *f = alloc_ba_mixed_frame(); if (++link_frames > max_link_frames) max_link_frames = link_frames; return (struct link_frame *) f; } static INLINE struct free_extra_frame *alloc_free_extra_frame() { struct ba_mixed_frame *f = alloc_ba_mixed_frame(); free_extra_frames++; return (struct free_extra_frame *) f; } static INLINE void really_free_link_frame (struct link_frame *f) { link_frames--; really_free_ba_mixed_frame ((struct ba_mixed_frame *) f); } static INLINE void really_free_free_extra_frame (struct free_extra_frame *f) { free_extra_frames--; really_free_ba_mixed_frame ((struct ba_mixed_frame *) f); } /* These are only collected for the sake of gc_status. */ static double last_garbage_ratio = 0.0; static enum { GARBAGE_RATIO_LOW, GARBAGE_RATIO_HIGH } last_garbage_strategy = GARBAGE_RATIO_LOW; struct callback_list gc_callbacks; /* These callbacks are run early in the check pass of the gc and when * locate_references is called. They are typically used to mark * external references (using gc_mark_external) for debug purposes. */ struct callback *debug_add_gc_callback(callback_func call, void *arg, callback_func free_func) { return add_to_callback(&gc_callbacks, call, arg, free_func); } static void init_gc(void); static void gc_cycle_pop(); #undef BLOCK_ALLOC_NEXT #define BLOCK_ALLOC_NEXT next #undef INIT_BLOCK #ifdef PIKE_DEBUG #define INIT_BLOCK(X) \ (X)->flags=(X)->refs=(X)->weak_refs=(X)->xrefs=0; \ (X)->saved_refs=-1; \ (X)->frame = 0; #else #define INIT_BLOCK(X) \ (X)->flags=(X)->refs=(X)->weak_refs=0; \ (X)->frame = 0; #endif #undef get_marker #define get_marker debug_get_marker #undef find_marker #define find_marker debug_find_marker PTR_HASH_ALLOC_FIXED_FILL_PAGES(marker,2) #undef get_marker #define get_marker(X) ((struct marker *) debug_malloc_pass(debug_get_marker(X))) #undef find_marker #define find_marker(X) ((struct marker *) debug_malloc_pass(debug_find_marker(X))) PMOD_EXPORT struct marker *pmod_get_marker (void *p) { return debug_get_marker (p); } PMOD_EXPORT struct marker *pmod_find_marker (void *p) { return debug_find_marker (p); } #if defined (PIKE_DEBUG) || defined (GC_MARK_DEBUG) void *gc_found_in = NULL; int gc_found_in_type = PIKE_T_UNKNOWN; const char *gc_found_place = NULL; #endif #ifdef DO_PIKE_CLEANUP /* To keep the markers after the gc. Only used for the leak report at exit. */ int gc_keep_markers = 0; PMOD_EXPORT int gc_external_refs_zapped = 0; #endif #if defined (PIKE_DEBUG) || defined (GC_CYCLE_DEBUG) static void describe_rec_frame (struct gc_rec_frame *f) { fprintf (stderr, "data=%p rf_flags=0x%02x prev=%p next=%p " "cycle_id=%p cycle_piece=%p link_top/last_cycle_piece=%p", f->data, f->rf_flags, f->prev, f->next, f->cycle_id, f->cycle_piece, f->u.link_top); } /* If p* isn't NULL then p*_name will be written out next to the * matching frame in the stack, if any is found. */ static void describe_rec_stack (struct gc_rec_frame *p1, const char *p1_name, struct gc_rec_frame *p2, const char *p2_name, struct gc_rec_frame *p3, const char *p3_name) { struct gc_rec_frame *l, *cp; size_t longest; if (p1) longest = strlen (p1_name); if (p2) {size_t l = strlen (p2_name); if (l > longest) longest = l;} if (p3) {size_t l = strlen (p3_name); if (l > longest) longest = l;} longest++; /* Note: Stack is listed from top to bottom, but cycle piece lists * are lists from first to last, i.e. reverse order. */ for (l = stack_top; l != &sentinel_frame; l = l->prev) { size_t c = 0; if (!l) {fputs (" <broken prev link in rec stack>\n", stderr); break;} fprintf (stderr, " %p", l); if (l == p1) {fprintf (stderr, " %s", p1_name); c += strlen (p1_name) + 1;} if (l == p2) {fprintf (stderr, " %s", p2_name); c += strlen (p2_name) + 1;} if (l == p3) {fprintf (stderr, " %s", p3_name); c += strlen (p3_name) + 1;} fprintf (stderr, ": %*s", c < longest ? (int) (longest - c) : 0, ""); describe_rec_frame (l); fputc ('\n', stderr); for (cp = l->cycle_piece; cp; cp = cp->cycle_piece) { fprintf (stderr, " %p", cp); c = 0; if (cp == p1) {fprintf (stderr, " %s", p1_name); c += strlen (p1_name)+1;} if (cp == p2) {fprintf (stderr, " %s", p2_name); c += strlen (p2_name)+1;} if (cp == p3) {fprintf (stderr, " %s", p3_name); c += strlen (p3_name)+1;} fprintf (stderr, ": %*s", c < longest ? (int) (longest - c) : 0, ""); describe_rec_frame (cp); fputc ('\n', stderr); } } } #endif #ifdef PIKE_DEBUG int gc_in_cycle_check = 0; static int gc_is_watching = 0; int attempt_to_identify(void *something, void **inblock) { size_t i; struct array *a; struct object *o; struct program *p; struct mapping *m; struct multiset *mu; struct pike_type *t; struct callable *c; if (inblock) *inblock = 0; for (a = first_array; a; a = a->next) { if(a==(struct array *)something) return T_ARRAY; } for(o=first_object;o;o=o->next) { if(o==(struct object *)something) return T_OBJECT; if (o->storage && o->prog && (char *) something >= o->storage && (char *) something < o->storage + o->prog->storage_needed) { if (inblock) *inblock = (void *) o; return T_STORAGE; } } for(p=first_program;p;p=p->next) if(p==(struct program *)something) return T_PROGRAM; for(m=first_mapping;m;m=m->next) if(m==(struct mapping *)something) return T_MAPPING; else if (m->data == (struct mapping_data *) something) return T_MAPPING_DATA; for(mu=first_multiset;mu;mu=mu->next) if(mu==(struct multiset *)something) return T_MULTISET; else if (mu->msd == (struct multiset_data *) something) return T_MULTISET_DATA; if(safe_debug_findstring((struct pike_string *)something)) return T_STRING; if (pike_type_hash) for (i = 0; i < pike_type_hash_size; i++) for (t = pike_type_hash[i]; t; t = t->next) if (t == (struct pike_type *) something) return T_TYPE; for (c = first_callable; c; c = c->next) if (c == (struct callable *) something) return T_STRUCT_CALLABLE; return PIKE_T_UNKNOWN; } void *check_for =0; void *gc_svalue_location=0; static size_t found_ref_count; char *fatal_after_gc=0; #define DESCRIBE_MEM 1 #define DESCRIBE_SHORT 4 #define DESCRIBE_NO_DMALLOC 8 /* type == -1 means that memblock is a char* and should be * really be printed.. */ void describe_location(void *real_memblock, int type, void *location, int indent, int depth, int flags) { struct program *p; void *memblock=0, *descblock, *inblock; if(!location) return; /* fprintf(stderr,"**Location of (short) svalue: %p\n",location); */ if(type!=-1 && real_memblock != (void *) -1) memblock=real_memblock; #ifdef DEBUG_MALLOC if(memblock == 0 || type == -1) { extern void *dmalloc_find_memblock_base(void *); memblock=dmalloc_find_memblock_base(location); } #endif if(type==PIKE_T_UNKNOWN) type=attempt_to_identify(memblock, &inblock); if(memblock) fprintf(stderr,"%*s-> from %s %p offset %"PRINTPTRDIFFT"d\n", indent,"", get_name_of_type(type), memblock, (char *)location - (char *)memblock); else fprintf(stderr,"%*s-> at location %p%s\n", indent,"", location, real_memblock == (void *) -1 ? "" : " in unknown memblock (mmaped?)"); again: descblock = memblock; switch(type) { case PIKE_T_UNKNOWN: for(p=first_program;p;p=p->next) { if(memblock == (void *)p->program) { fprintf(stderr,"%*s **In memory block for program at %p\n", indent,"", p); memblock=p; type=T_PROGRAM; goto again; } } break; case T_PROGRAM: { ptrdiff_t e; char *ptr=(char *)location; p=(struct program *)memblock; if(location == (void *)&p->prev) fprintf(stderr,"%*s **In p->prev\n",indent,""); if(location == (void *)&p->next) fprintf(stderr,"%*s **In p->next\n",indent,""); if(location == (void *)&p->parent) fprintf(stderr,"%*s **In p->parent\n",indent,""); if(p->inherits && ptr >= (char *)p->inherits && ptr < (char*)(p->inherits+p->num_inherits)) { e=((char *)ptr - (char *)(p->inherits)) / sizeof(struct inherit); fprintf(stderr,"%*s **In p->inherits[%"PRINTPTRDIFFT"d] (%s)\n",indent,"", e, p->inherits[e].name ? p->inherits[e].name->str : "no name"); break; } if(p->constants && ptr >= (char *)p->constants && ptr < (char*)(p->constants+p->num_constants)) { e = ((char *)ptr - (char *)(p->constants)) / sizeof(struct program_constant); #if 0 fprintf(stderr,"%*s **In p->constants[%"PRINTPTRDIFFT"d] (%s)\n",indent,"", e, p->constants[e].name ? p->constants[e].name->str : "no name"); #else /* !0 */ fprintf(stderr,"%*s **In p->constants[%"PRINTPTRDIFFT"d] " "(%"PRINTPTRDIFFT"d)\n",indent,"", e, p->constants[e].offset); #endif /* 0 */ break; } if(p->identifiers && ptr >= (char *)p->identifiers && ptr < (char*)(p->identifiers+p->num_identifiers)) { e = ((char *)ptr - (char *)(p->identifiers)) / sizeof(struct identifier); fprintf(stderr,"%*s **In p->identifiers[%"PRINTPTRDIFFT"d] (%s)\n",indent,"", e, p->identifiers[e].name ? (strlen(p->identifiers[e].name->str)<100 ? p->identifiers[e].name->str : "Name too long or already freed.." ) : "no name"); break; } #define FOO(NUMTYPE,TYPE,ARGTYPE,NAME) \ if(location == (void *)&p->NAME) fprintf(stderr,"%*s **In p->" #NAME "\n",indent,""); \ if(ptr >= (char *)p->NAME && ptr<(char*)(p->NAME+p->PIKE_CONCAT(num_,NAME))) \ fprintf(stderr,"%*s **In p->" #NAME "[%"PRINTPTRDIFFT"d]\n",indent,"", \ ((char *)ptr - (char *)(p->NAME)) / sizeof(TYPE)); #include "program_areas.h" break; } case T_OBJECT: { struct object *o=(struct object *)memblock; struct program *p; if(o->prog && o->prog->flags & PROGRAM_USES_PARENT) { if(location == (void *)&PARENT_INFO(o)->parent) fprintf(stderr,"%*s **In o->parent\n",indent,""); } if(location == (void *)&o->prog) fprintf(stderr,"%*s **In o->prog\n",indent,""); if(location == (void *)&o->next) fprintf(stderr,"%*s **In o->next\n",indent,""); if(location == (void *)&o->prev) fprintf(stderr,"%*s **In o->prev\n",indent,""); p=o->prog; if(!o->prog) { p=id_to_program(o->program_id); if(p) fprintf(stderr,"%*s **(We are lucky, found program for destructed object)\n",indent,""); } if(p) { INT32 e,d; for(e=0;e<(INT32)p->num_inherits;e++) { struct inherit tmp=p->inherits[e]; char *base=o->storage + tmp.storage_offset; for(d=0;d<(INT32)tmp.prog->num_identifiers;d++) { struct identifier *id=tmp.prog->identifiers+d; if(!IDENTIFIER_IS_VARIABLE(id->identifier_flags)) continue; if(location == (void *)(base + id->func.offset)) { fprintf(stderr,"%*s **In variable %s\n",indent,"",id->name->str); } } if((char *)location >= base && (char *)location <= base + ( tmp.prog->storage_needed - tmp.prog->inherits[0].storage_offset )) { fprintf(stderr,"%*s **In storage for inherit %d",indent,"",e); if(tmp.name && !tmp.name->size_shift) fprintf(stderr," (%s)",tmp.name->str); fprintf(stderr,"\n"); } } } break; } case T_STORAGE: fprintf(stderr, "%*s **In storage of object\n", indent, ""); break; case T_MULTISET: descblock = ((struct multiset *) memblock)->msd; /* FALL THROUGH */ case T_MULTISET_DATA: { struct multiset_data *msd = (struct multiset_data *) descblock; union msnode *node = low_multiset_first (msd); struct svalue ind; int indval = msd->flags & MULTISET_INDVAL; for (; node; node = low_multiset_next (node)) { if (&node->i.ind == (struct svalue *) location) { fprintf (stderr, "%*s **In index ", indent, ""); safe_print_svalue (stderr, low_use_multiset_index (node, ind)); fputc ('\n', stderr); break; } else if (indval && &node->iv.val == (struct svalue *) location) { fprintf(stderr, "%*s **In value with index ", indent, ""); safe_print_svalue (stderr, low_use_multiset_index (node, ind)); fputc('\n', stderr); break; } } break; } case T_ARRAY: { struct array *a=(struct array *)descblock; struct svalue *s=(struct svalue *)location; if(location == (void *)&a->next) fprintf(stderr,"%*s **In a->next\n",indent,""); if(location == (void *)&a->prev) fprintf(stderr,"%*s **In a->prev\n",indent,""); if( s-ITEM(a) > 0) fprintf(stderr,"%*s **In index number %"PRINTPTRDIFFT"d\n",indent,"", s-ITEM(a)); break; } case T_MAPPING: descblock = ((struct mapping *) memblock)->data; /* FALL THROUGH */ case T_MAPPING_DATA: { INT32 e; struct keypair *k; NEW_MAPPING_LOOP((struct mapping_data *) descblock) if (&k->ind == (struct svalue *) location) { fprintf(stderr, "%*s **In index ", indent, ""); safe_print_svalue (stderr, &k->ind); fputc('\n', stderr); break; } else if (&k->val == (struct svalue *) location) { fprintf(stderr, "%*s **In value with index ", indent, ""); safe_print_svalue (stderr, &k->ind); fputc('\n', stderr); break; } break; } case T_PIKE_FRAME: { struct pike_frame *f = (struct pike_frame *) descblock; if (f->locals) { /* Paranoia. */ ptrdiff_t pos = (struct svalue *) location - f->locals; if (pos >= 0) { if (pos < f->num_args) fprintf (stderr, "%*s **In argument %"PRINTPTRDIFFT"d\n", indent, "", pos); else fprintf (stderr, "%*s **At position %"PRINTPTRDIFFT"d among locals\n", indent, "", pos - f->num_args); /* Don't describe current_object for the frame. */ flags |= DESCRIBE_SHORT; } } break; } } if(memblock && depth>0) describe_something(memblock,type,indent+2,depth-1,flags,inblock); #ifdef DEBUG_MALLOC /* FIXME: Is the following call correct? * Shouldn't the second argument be an offset? */ /* dmalloc_describe_location(descblock, location, indent); */ /* My attempt to fix it, although I'm not really sure: /mast */ if (memblock) dmalloc_describe_location(memblock, (char *) location - (char *) memblock, indent); #endif } static void describe_link_frame (struct link_frame *f) { fprintf (stderr, "data=%p prev=%p checkfn=%p weak=%d", f->data, f->prev, f->checkfn, f->weak); } static void describe_marker(struct marker *m) { if (m) { fprintf(stderr, "marker at %p: flags=0x%05lx refs=%d weak=%d " "xrefs=%d saved=%d frame=%p", m, (long) m->flags, m->refs, m->weak_refs, m->xrefs, m->saved_refs, m->frame); if (m->frame) { fputs(" [", stderr); describe_rec_frame (m->frame); putc(']', stderr); } putc('\n', stderr); } else fprintf(stderr, "no marker\n"); } #endif /* PIKE_DEBUG */ static void debug_gc_fatal_va (void *a, int flags, const char *fmt, va_list args) { #ifdef PIKE_DEBUG struct marker *m; #endif int orig_gc_pass = Pike_in_gc; (void) VFPRINTF(stderr, fmt, args); #ifdef PIKE_DEBUG if (a) { /* Temporarily jumping out of gc to avoid being caught in debug * checks in describe(). */ Pike_in_gc = 0; describe(a); if (flags & 1) locate_references(a); m=find_marker(a); if(m) { fprintf(stderr,"** Describing marker for this thing.\n"); describe(m); }else{ fprintf(stderr,"** No marker found for this thing.\n"); } Pike_in_gc = orig_gc_pass; } if (flags & 2) fatal_after_gc = "Fatal in garbage collector.\n"; else #endif { d_flag = 0; /* The instruction backlog is never of any use here. */ debug_fatal (NULL); } } void debug_gc_fatal (void *a, int flags, const char *fmt, ...) { va_list args; va_start (args, fmt); debug_gc_fatal_va (a, flags, fmt, args); va_end (args); } static void dloc_gc_fatal (const char *file, int line, void *a, int flags, const char *fmt, ...) { va_list args; fprintf (stderr, "%s:%d: GC fatal:\n", file, line); va_start (args, fmt); debug_gc_fatal_va (a, flags, fmt, args); va_end (args); } static void rec_stack_fatal (struct gc_rec_frame *err, const char *err_name, struct gc_rec_frame *p1, const char *p1n, struct gc_rec_frame *p2, const char *p2n, const char *file, int line, const char *fmt, ...) { va_list args; va_start (args, fmt); fprintf (stderr, msg_fatal_error, file, line); (void) VFPRINTF (stderr, fmt, args); #if defined (PIKE_DEBUG) || defined (GC_CYCLE_DEBUG) fputs ("Recursion stack:\n", stderr); describe_rec_stack (err, err_name, p1, p1n, p2, p2n); if (err) { fprintf (stderr, "Describing frame %p: ", err); describe_rec_frame (err); fputc ('\n', stderr); } #endif d_flag = 0; /* The instruction backlog is never of any use here. */ debug_fatal (NULL); va_end (args); } #ifdef PIKE_DEBUG static void gdb_gc_stop_here(void *a, int weak) { found_ref_count++; fprintf(stderr,"***One %sref found%s. ", weak ? "weak " : "", gc_found_place ? gc_found_place : ""); if (gc_found_in) { if (gc_svalue_location) describe_location(gc_found_in , gc_found_in_type, gc_svalue_location,0,1, DESCRIBE_SHORT); else { fputc('\n', stderr); describe_something(gc_found_in, gc_found_in_type, 0, 0, DESCRIBE_SHORT, 0); } } else fputc('\n', stderr); fprintf(stderr,"----------end------------\n"); } void low_describe_something(void *a, int t, int indent, int depth, int flags, void *inblock) { struct program *p=(struct program *)a; struct marker *m; if(depth<0) return; if (marker_hash_table && (m = find_marker(a))) { fprintf(stderr,"%*s**Got gc ",indent,""); describe_marker(m); } again: switch(t) { case T_STORAGE: if (!inblock) attempt_to_identify (a, &a); t = T_OBJECT; goto again; case T_FUNCTION: if(attempt_to_identify(a, 0) != T_OBJECT) { fprintf(stderr,"%*s**Builtin function!\n",indent,""); break; } /* FALL THROUGH */ case T_OBJECT: p=((struct object *)a)->prog; if(p && (p->flags & PROGRAM_USES_PARENT)) { fprintf(stderr,"%*s**Parent identifier: %d\n",indent,"",PARENT_INFO( ((struct object *)a) )->parent_identifier); } fprintf(stderr,"%*s**Program id: %d\n",indent,"",((struct object *)a)->program_id); if (((struct object *)a)->next == ((struct object *)a)) fprintf(stderr, "%*s**The object is fake.\n",indent,""); { struct object *o; for (o = first_object; o && o != (struct object *) a; o = o->next) {} if (!o) fprintf(stderr,"%*s**The object is not on the object link list.\n",indent,""); for (o = objects_to_destruct; o && o != (struct object *) a; o = o->next) {} if (o) fprintf(stderr,"%*s**The object is on objects_to_destruct.\n",indent,""); } if(!p) { p=id_to_program(((struct object *)a)->program_id); if(p) fprintf(stderr,"%*s**The object is destructed but program found from id.\n", indent,""); else fprintf(stderr,"%*s**The object is destructed and program not found from id.\n", indent,""); } if (((struct object *) a)->refs > 0 && p) { size_t inh_idx, var_idx, var_count = 0; if (((struct object *)a)->prog) { fprintf (stderr, "%*s**Object variables:\n", indent, ""); for (inh_idx = 0; inh_idx < p->num_inherits; inh_idx++) { struct inherit *inh = p->inherits + inh_idx; struct program *p2 = inh->prog; if (inh->inherit_level) { if (inh->name) { fprintf (stderr, "%*s**%*s=== In inherit ", indent, "", inh->inherit_level + 1, ""); safe_print_short_svalue (stderr, (union anything *) &inh->name, T_STRING); fprintf (stderr, ", program %d:\n", inh->prog->id); } else fprintf (stderr, "%*s**%*s=== In nameless inherit, program %d:\n", indent, "", inh->inherit_level + 1, "", inh->prog->id); } for (var_idx = 0; var_idx < p2->num_variable_index; var_idx++) { struct identifier *id = p2->identifiers + p2->variable_index[var_idx]; void *ptr; fprintf (stderr, "%*s**%*srtt: %-8s name: ", indent, "", inh->inherit_level + 1, "", get_name_of_type (id->run_time_type)); if (id->name->size_shift) safe_print_short_svalue (stderr, (union anything *) &id->name, T_STRING); else fprintf (stderr, "%-20s", id->name->str); fprintf (stderr, " off: %4"PRINTPTRDIFFT"d value: ", inh->storage_offset + id->func.offset); ptr = PIKE_OBJ_STORAGE ((struct object *) a) + inh->storage_offset + id->func.offset; if (id->run_time_type == T_MIXED) safe_print_svalue_compact (stderr, (struct svalue *) ptr); else safe_print_short_svalue_compact (stderr, (union anything *) ptr, id->run_time_type); fputc ('\n', stderr); var_count++; } } if (!var_count) fprintf (stderr, "%*s** (none)\n", indent, ""); } fprintf(stderr,"%*s**Describing program %p of object:\n",indent,"", p); #ifdef DEBUG_MALLOC if ((INT32)(ptrdiff_t) p == 0x55555555) fprintf(stderr, "%*s**Zapped program pointer.\n", indent, ""); else #endif low_describe_something(p, T_PROGRAM, indent, depth, depth ? flags : flags | DESCRIBE_SHORT, 0); if((p->flags & PROGRAM_USES_PARENT) && LOW_PARENT_INFO(((struct object *)a),p)->parent) { if (depth) { fprintf(stderr,"%*s**Describing parent of object:\n",indent,""); describe_something( PARENT_INFO((struct object *)a)->parent, T_OBJECT, indent+2, depth-1, (flags | DESCRIBE_SHORT) & ~DESCRIBE_MEM, 0); } else fprintf (stderr, "%*s**Object got a parent.\n", indent, ""); }else{ fprintf(stderr,"%*s**There is no parent (any longer?)\n",indent,""); } } break; case T_PROGRAM: { char *tmp; INT32 line; ptrdiff_t id_idx, id_count = 0; struct inherit *inh = p->inherits, *next_inh = p->inherits + 1; ptrdiff_t inh_id_end = p->num_identifier_references; fprintf(stderr,"%*s**Program id: %ld, flags: %x, parent id: %d\n", indent,"", (long)(p->id), p->flags, p->parent ? p->parent->id : -1); if(p->flags & PROGRAM_HAS_C_METHODS) { fprintf(stderr,"%*s**The program was written in C.\n",indent,""); } tmp = low_get_program_line_plain(p, &line, 1); if (tmp) { fprintf(stderr,"%*s**Location: %s:%ld\n", indent, "", tmp, (long)line); free (tmp); } if (!(flags & DESCRIBE_SHORT) && p->refs > 0) { fprintf (stderr, "%*s**Identifiers:\n", indent, ""); for (id_idx = 0; id_idx < p->num_identifier_references; id_idx++) { struct reference *id_ref = p->identifier_references + id_idx; struct inherit *id_inh; struct identifier *id; const char *type; char prot[100], descr[120]; while (next_inh < p->inherits + p->num_inherits && id_idx == next_inh->identifier_level) { inh = next_inh++; inh_id_end = inh->identifier_level + inh->prog->num_identifier_references; if (inh->name) { fprintf (stderr, "%*s**%*s=== In inherit ", indent, "", inh->inherit_level + 1, ""); safe_print_short_svalue (stderr, (union anything *) &inh->name, T_STRING); fprintf (stderr, ", program %d:\n", inh->prog->id); } else fprintf (stderr, "%*s**%*s=== In nameless inherit, program %d:\n", indent, "", inh->inherit_level + 1, "", inh->prog->id); } while (id_idx == inh_id_end) { int cur_lvl = inh->inherit_level; if (inh->name) { fprintf (stderr, "%*s**%*s=== End of inherit ", indent, "", inh->inherit_level + 1, ""); safe_print_short_svalue (stderr, (union anything *) &inh->name, T_STRING); fputc ('\n', stderr); } else fprintf (stderr, "%*s**%*s=== End of nameless inherit\n", indent, "", inh->inherit_level + 1, ""); while (inh > p->inherits) { /* Paranoia. */ if ((--inh)->inherit_level < cur_lvl) break; } inh_id_end = inh->identifier_level + inh->prog->num_identifier_references; } #if 0 /* Can be illuminating to see these too.. */ if (id_ref->id_flags & ID_HIDDEN || (id_ref->id_flags & (ID_INHERITED|ID_PRIVATE)) == (ID_INHERITED|ID_PRIVATE)) continue; #endif id_inh = INHERIT_FROM_PTR (p, id_ref); id = id_inh->prog->identifiers + id_ref->identifier_offset; if (IDENTIFIER_IS_ALIAS (id->identifier_flags)) type = "alias"; else if (IDENTIFIER_IS_PIKE_FUNCTION (id->identifier_flags)) type = "fun"; else if (IDENTIFIER_IS_FUNCTION (id->identifier_flags)) type = "cfun"; else if (IDENTIFIER_IS_CONSTANT (id->identifier_flags)) type = "const"; else if (IDENTIFIER_IS_VARIABLE (id->identifier_flags)) type = "var"; else type = "???"; prot[0] = prot[1] = 0; if (id_ref->id_flags & ID_PRIVATE) { strcat (prot, ",pri"); if (!(id_ref->id_flags & ID_PROTECTED)) strcat (prot, ",!pro"); } else if (id_ref->id_flags & ID_PROTECTED) strcat (prot, ",pro"); if (id_ref->id_flags & ID_FINAL) strcat (prot, ",fin"); if (id_ref->id_flags & ID_PUBLIC) strcat (prot, ",pub"); if (id_ref->id_flags & ID_INLINE) strcat (prot, ",inl"); if (id_ref->id_flags & ID_OPTIONAL) strcat (prot, ",opt"); if (id_ref->id_flags & ID_HIDDEN) strcat (prot, ",hid"); if (id_ref->id_flags & ID_INHERITED) strcat (prot, ",inh"); if (id_ref->id_flags & ID_EXTERN) strcat (prot, ",ext"); if (id_ref->id_flags & ID_VARIANT) strcat (prot, ",var"); if (id_ref->id_flags & ID_USED) strcat (prot, ",use"); sprintf (descr, "%s: %s", type, prot + 1); fprintf (stderr, "%*s**%*s%-3"PRINTPTRDIFFT"d %-18s name: ", indent, "", id_inh->inherit_level + 1, "", id_idx, descr); if (id->name->size_shift) safe_print_short_svalue (stderr, (union anything *) &id->name, T_STRING); else fprintf (stderr, "%-20s", id->name->str); if (IDENTIFIER_IS_ALIAS(id->identifier_flags)) { fprintf(stderr, " depth: %d id: %d", id->func.ext_ref.depth, id->func.ext_ref.id); } else if (id->identifier_flags & IDENTIFIER_C_FUNCTION) fprintf (stderr, " addr: %p", id->func.c_fun); else if (IDENTIFIER_IS_VARIABLE (id->identifier_flags)) fprintf (stderr, " rtt: %s off: %"PRINTPTRDIFFT"d", get_name_of_type (id->run_time_type), id->func.offset); else if (IDENTIFIER_IS_PIKE_FUNCTION (id->identifier_flags)) fprintf (stderr, " pc: %"PRINTPTRDIFFT"d", id->func.offset); else if (IDENTIFIER_IS_CONSTANT (id->identifier_flags)) { fputs (" value: ", stderr); safe_print_svalue_compact ( stderr, &id_inh->prog->constants[id->func.offset].sval); } fputc ('\n', stderr); id_count++; } if (!id_count) fprintf (stderr, "%*s** (none)\n", indent, ""); } if(flags & DESCRIBE_MEM) { #define FOO(NUMTYPE,TYPE,ARGTYPE,NAME) \ fprintf(stderr, "%*s* " #NAME " %p[%"PRINTSIZET"u]\n", \ indent, "", p->NAME, (size_t)p->PIKE_CONCAT(num_,NAME)); #include "program_areas.h" } break; } case T_MULTISET_DATA: { int found = 0; struct multiset *l; for (l = first_multiset; l; l = l->next) { if (l->msd == (struct multiset_data *) a) { fprintf(stderr, "%*s**Describing multiset %p for this data block:\n", indent, "", l); debug_dump_multiset(l); found = 1; } } if (!found) fprintf (stderr, "%*s**Didn't find multiset for this data block!\n", indent, ""); break; } case T_MULTISET: if (((struct multiset *) a)->refs > 0) debug_dump_multiset((struct multiset *) a); break; case T_ARRAY: if (((struct array *) a)->refs > 0) debug_dump_array((struct array *)a); break; case T_MAPPING_DATA: { int found = 0; struct mapping *m; for(m=first_mapping;m;m=m->next) { if(m->data == (struct mapping_data *)a) { fprintf(stderr,"%*s**Describing mapping for this data block:\n",indent,""); debug_dump_mapping((struct mapping *)m); found = 1; } } if (!found) fprintf (stderr, "%*s**Didn't find mapping for this data block!\n", indent, ""); break; } case T_MAPPING: if (((struct mapping *) a)->refs > 0) debug_dump_mapping((struct mapping *)a); break; case T_STRING: { struct pike_string *s=(struct pike_string *)a; fprintf(stderr,"%*s**size_shift: %d, " "len: %"PRINTPTRDIFFT"d, " "hash: %"PRINTSIZET"x\n", indent,"", s->size_shift, s->len, s->hval); if (!s->size_shift && s->refs > 0) { if(s->len>77) { fprintf(stderr,"%*s** \"%60s\"...\n",indent,"",s->str); }else{ fprintf(stderr,"%*s** \"%s\"\n",indent,"",s->str); } } break; } case PIKE_T_TYPE: { fprintf(stderr, "%*s**type: ", indent, ""); simple_describe_type((struct pike_type *)a); fprintf(stderr, "\n"); break; } case T_PIKE_FRAME: { struct pike_frame *f = (struct pike_frame *) a; do { if (f->refs <= 0) break; if (f->current_object) { struct program *p = f->current_object->prog; if (p) { struct identifier *id = ID_FROM_INT(p, f->fun); INT32 line; struct pike_string *file; if (IDENTIFIER_IS_PIKE_FUNCTION(id->identifier_flags) && id->func.offset >= 0 && (file = get_line(p->program + id->func.offset, p, &line))) { fprintf(stderr, "%*s**Function %s at %s:%ld\n", indent, "", id->name->str, file->str, (long) line); free_string(file); } else fprintf(stderr, "%*s**Function %s at unknown location.\n", indent, "", id->name->str); } if (!(flags & DESCRIBE_SHORT)) { fprintf(stderr, "%*s**Describing the current object:\n", indent, ""); describe_something(f->current_object, T_OBJECT, indent+2, depth, flags, 0); } } else fprintf(stderr, "%*s**No current object.\n", indent, ""); if ((f = f->scope)) fprintf(stderr, "%*s**Moving on to outer scope frame %p:\n", indent, "", f); } while (f); break; } default: fprintf(stderr, "%*s**Cannot describe block of type %s (%d)\n", indent, "", get_name_of_type (t), t); } } void describe_something(void *a, int t, int indent, int depth, int flags, void *inblock) { int tmp; struct program *p=(struct program *)a; if(!a) { fprintf (stderr, "%*s**NULL pointer\n", indent, ""); return; } if(t==-1) { fprintf(stderr,"%*s**Location description: %s\n",indent,"",(char *)a); return; } /* Disable debug, this may help reduce recursion bugs */ tmp=d_flag; d_flag=0; #ifdef DEBUG_MALLOC if (((INT32)(ptrdiff_t)a) == 0x55555555) { fprintf(stderr,"%*s**Block: %p Type: %s Zapped pointer\n",indent,"",a, get_name_of_type(t)); } else #endif /* DEBUG_MALLOC */ if (((ptrdiff_t)a) & 3) { fprintf(stderr,"%*s**Block: %p Type: %s Misaligned address\n",indent,"",a, get_name_of_type(t)); } else { fprintf(stderr,"%*s**Block: %p Type: %s Refs: %d\n",indent,"",a, get_name_of_type(t), *(INT32 *)a); low_describe_something(a,t,indent,depth,flags,inblock); #ifdef DEBUG_MALLOC if(!(flags & DESCRIBE_NO_DMALLOC)) debug_malloc_dump_references(a,indent+2,depth-1,flags); #endif } fprintf(stderr,"%*s*******************\n",indent,""); d_flag=tmp; } PMOD_EXPORT void describe(void *x) { void *inblock; int type = attempt_to_identify(x, &inblock); describe_something(x, type, 0, 0, 0, inblock); } void debug_describe_svalue(struct svalue *s) { fprintf(stderr,"Svalue at %p is:\n",s); switch(s->type) { case T_INT: fprintf(stderr," %"PRINTPIKEINT"d (subtype %d)\n",s->u.integer, s->subtype); break; case T_FLOAT: fprintf(stderr," %"PRINTPIKEFLOAT"f\n",s->u.float_number); break; case T_FUNCTION: if(s->subtype == FUNCTION_BUILTIN) { fprintf(stderr," Builtin function: %s\n",s->u.efun->name->str); }else{ if(!s->u.object->prog) { struct program *p=id_to_program(s->u.object->program_id); if(p) { fprintf(stderr," Function in destructed object: %s\n", ID_FROM_INT(p,s->subtype)->name->str); }else{ fprintf(stderr," Function in destructed object.\n"); } }else{ fprintf(stderr," Function name: %s\n", ID_FROM_INT(s->u.object->prog,s->subtype)->name->str); } } } describe_something(s->u.refs,s->type,0,1,0,0); } void gc_watch(void *a) { struct marker *m; init_gc(); m = get_marker(a); if (!(m->flags & GC_WATCHED)) { m->flags |= GC_WATCHED; fprintf(stderr, "## Watching thing %p.\n", a); gc_is_watching++; } else fprintf(stderr, "## Already watching thing %p.\n", a); } static void gc_watched_found (struct marker *m, const char *found_in) { fprintf(stderr, "## Watched thing %p with %d refs found in " "%s in pass %d.\n", m->data, *(INT32 *) m->data, found_in, Pike_in_gc); describe_marker (m); } #endif /* PIKE_DEBUG */ #ifndef GC_MARK_DEBUG struct pike_queue gc_mark_queue; #else /* !GC_MARK_DEBUG */ /* Cut'n'paste from queue.c. */ struct gc_queue_entry { queue_call call; void *data; int in_type; void *in; const char *place; }; #define GC_QUEUE_ENTRIES 8191 struct gc_queue_block { struct gc_queue_block *next; int used; struct gc_queue_entry entries[GC_QUEUE_ENTRIES]; }; struct gc_queue_block *gc_mark_first = NULL, *gc_mark_last = NULL; void gc_mark_run_queue() { struct gc_queue_block *b; while((b=gc_mark_first)) { int e; for(e=0;e<b->used;e++) { debug_malloc_touch(b->entries[e].data); b->entries[e].call(b->entries[e].data); } gc_mark_first=b->next; free((char *)b); } gc_mark_last=0; } void gc_mark_discard_queue() { struct gc_queue_block *b = gc_mark_first; while (b) { struct gc_queue_block *next = b->next; free((char *) b); b = next; } gc_mark_first = gc_mark_last = 0; } void gc_mark_enqueue (queue_call call, void *data) { struct gc_queue_block *b; #ifdef PIKE_DEBUG if (gc_found_in_type == PIKE_T_UNKNOWN || !gc_found_in) gc_fatal (data, 0, "gc_mark_enqueue() called outside GC_ENTER.\n"); { struct marker *m; if (gc_is_watching && (m = find_marker(data)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_mark_enqueue()"); } } #endif b=gc_mark_last; if(!b || b->used >= GC_QUEUE_ENTRIES) { b = (struct gc_queue_block *) malloc (sizeof (struct gc_queue_block)); if (!b) fatal ("Out of memory in gc.\n"); b->used=0; b->next=0; if(gc_mark_first) gc_mark_last->next=b; else gc_mark_first=b; gc_mark_last=b; } b->entries[b->used].call=call; b->entries[b->used].data=debug_malloc_pass(data); b->entries[b->used].in_type = gc_found_in_type; b->entries[b->used].in = debug_malloc_pass (gc_found_in); b->entries[b->used].place = gc_found_place; b->used++; } #endif /* GC_MARK_DEBUG */ void debug_gc_touch(void *a) { struct marker *m; #ifdef PIKE_DEBUG if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_touch()"); } #endif if (!a) Pike_fatal("Got null pointer.\n"); switch (Pike_in_gc) { case GC_PASS_PRETOUCH: m = find_marker(a); if ( #ifdef DO_PIKE_CLEANUP !gc_keep_markers && #endif m && !(m->flags & (GC_PRETOUCHED #ifdef PIKE_DEBUG |GC_WATCHED #endif ))) gc_fatal(a, 1, "Thing got an existing but untouched marker.\n"); m = get_marker(a); m->flags |= GC_PRETOUCHED; #ifdef PIKE_DEBUG m->saved_refs = *(INT32 *) a; #endif break; case GC_PASS_POSTTOUCH: { #ifdef PIKE_DEBUG int extra_ref; #endif m = find_marker(a); if (!m) gc_fatal(a, 1, "Found a thing without marker.\n"); else if (!(m->flags & GC_PRETOUCHED)) gc_fatal(a, 1, "Thing got an existing but untouched marker.\n"); if (gc_destruct_everything && (m->flags & GC_MARKED)) gc_fatal (a, 1, "Thing got marked in gc_destruct_everything mode.\n"); #ifdef PIKE_DEBUG extra_ref = (m->flags & GC_GOT_EXTRA_REF) == GC_GOT_EXTRA_REF; if (m->saved_refs + extra_ref < *(INT32 *) a) if (m->flags & GC_WEAK_FREED) gc_fatal(a, 1, "Something failed to remove weak reference(s) to thing, " "or it has gotten more references since gc start.\n"); else gc_fatal(a, 1, "Thing has gotten more references since gc start.\n"); else if (m->weak_refs > m->saved_refs) gc_fatal(a, 0, "A thing got more weak references than references.\n"); #endif m->flags |= GC_POSTTOUCHED; break; } default: Pike_fatal("debug_gc_touch() used in invalid gc pass.\n"); } } #ifdef PIKE_DEBUG static INLINE struct marker *gc_check_debug(void *a, int weak) { struct marker *m; if (!a) Pike_fatal("Got null pointer.\n"); if(Pike_in_gc == GC_PASS_LOCATE) { if(check_for == a) { gdb_gc_stop_here(a, weak); } return 0; } #if 0 fprintf (stderr, "Ref: %s %p -> %p%s\n", get_name_of_type (gc_found_in_type), gc_found_in, a, gc_found_place ? gc_found_place : ""); #endif if (Pike_in_gc != GC_PASS_CHECK) Pike_fatal("gc check attempted in invalid pass.\n"); m = get_marker(a); if (!*(INT32 *)a) gc_fatal(a, 1, "GC check on thing without refs.\n"); if (m->saved_refs == -1) m->saved_refs = *(INT32 *)a; else if (m->saved_refs != *(INT32 *)a) gc_fatal(a, 1, "Refs changed in gc check pass.\n"); if (m->refs + m->xrefs >= *(INT32 *) a) /* m->refs will be incremented by the caller. */ gc_fatal (a, 1, "Thing is getting more internal refs (%d + %d) " "than refs (%d).\n" "(Could be an extra free somewhere, or " "a pointer might have been checked more than once.)\n", m->refs, m->xrefs, *(INT32 *) a); checked++; return m; } #endif /* PIKE_DEBUG */ PMOD_EXPORT INT32 real_gc_check(void *a) { struct marker *m; INT32 ret; #ifdef PIKE_DEBUG if (gc_found_in_type == PIKE_T_UNKNOWN || !gc_found_in) gc_fatal (a, 0, "gc_check() called outside GC_ENTER.\n"); if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_check()"); } if (!(m = gc_check_debug(a, 0))) return 0; #else m = get_marker(a); #endif ret=m->refs; add_ref(m); if (m->refs == *(INT32 *) a) m->flags |= GC_NOT_REFERENCED; return ret; } PMOD_EXPORT INT32 real_gc_check_weak(void *a) { struct marker *m; INT32 ret; #ifdef PIKE_DEBUG if (gc_found_in_type == PIKE_T_UNKNOWN || !gc_found_in) gc_fatal (a, 0, "gc_check_weak() called outside GC_ENTER.\n"); if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_check_weak()"); } if (!(m = gc_check_debug(a, 1))) return 0; if (m->weak_refs < 0) gc_fatal(a, 1, "Thing has already reached threshold for weak free.\n"); if (m->weak_refs >= *(INT32 *) a) gc_fatal(a, 1, "Thing has gotten more weak refs than refs.\n"); if (m->weak_refs > m->refs + 1) gc_fatal(a, 1, "Thing has gotten more weak refs than internal refs.\n"); #else m = get_marker(a); #endif m->weak_refs++; gc_ext_weak_refs++; if (m->weak_refs == *(INT32 *) a) m->weak_refs = -1; ret=m->refs; add_ref(m); if (m->refs == *(INT32 *) a) m->flags |= GC_NOT_REFERENCED; return ret; } static void cleanup_markers (void) { #ifdef DO_PIKE_CLEANUP size_t e=0; if (gc_keep_markers) { /* Carry over any GC_CLEANUP_LEAKED flags but reinitialize them * otherwise. */ for(e=0;e<marker_hash_table_size;e++) { struct marker *m; for (m = marker_hash_table[e]; m; m = m->next) { #ifdef PIKE_DEBUG m->flags &= GC_CLEANUP_LEAKED; m->xrefs = 0; m->saved_refs = -1; #else m->flags = 0; #endif m->refs = m->weak_refs = 0; m->frame = 0; } } return; } for(e=0;e<marker_hash_table_size;e++) while(marker_hash_table[e]) remove_marker(marker_hash_table[e]->data); #endif exit_marker_hash(); } static void init_gc(void) { #ifdef PIKE_DEBUG if (!gc_is_watching) { #endif #if defined (PIKE_DEBUG) || defined (DO_PIKE_CLEANUP) /* The marker hash table is left around after a previous gc if * gc_keep_markers is set. */ if (marker_hash_table) cleanup_markers(); if (!marker_hash_table) #endif low_init_marker_hash(num_objects); #ifdef PIKE_DEBUG } #endif } void exit_gc(void) { if (gc_evaluator_callback) { remove_callback(gc_evaluator_callback); gc_evaluator_callback = NULL; } if (!gc_keep_markers) cleanup_markers(); free_all_gc_rec_frame_blocks(); free_all_ba_mixed_frame_blocks(); #ifdef PIKE_DEBUG if (gc_is_watching) { fprintf(stderr, "## Exiting gc and resetting watches for %d things.\n", gc_is_watching); gc_is_watching = 0; } #endif } #ifdef PIKE_DEBUG PMOD_EXPORT void gc_check_zapped (void *a, TYPE_T type, const char *file, int line) { struct marker *m = find_marker (a); if (m && (m->flags & GC_CLEANUP_LEAKED)) fprintf (stderr, "Free of leaked %s %p from %s:%d, %d refs remaining\n", get_name_of_type (type), a, file, line, *(INT32 *)a - 1); } /* This function marks some known externals. The rest are handled by * callbacks added with add_gc_callback. */ static void mark_externals (void) { struct mapping *constants; if (master_object) gc_mark_external (master_object, " as master_object"); if ((constants = get_builtin_constants())) gc_mark_external (constants, " as global constants mapping"); } void locate_references(void *a) { int tmp, orig_in_gc = Pike_in_gc; const char *orig_gc_found_place = gc_found_place; int i=0; if(!marker_blocks) { i=1; init_gc(); } Pike_in_gc = GC_PASS_LOCATE; gc_found_place = NULL; /* Disable debug, this may help reduce recursion bugs */ tmp=d_flag; d_flag=0; fprintf(stderr,"**Looking for references to %p:\n", a); check_for=a; found_ref_count = 0; GC_ENTER (NULL, PIKE_T_UNKNOWN) { mark_externals(); call_callback(& gc_callbacks, NULL); gc_check_all_arrays(); gc_check_all_multisets(); gc_check_all_mappings(); gc_check_all_programs(); gc_check_all_objects(); gc_check_all_types(); } GC_LEAVE; #ifdef DEBUG_MALLOC { extern void dmalloc_find_references_to(void *); #if 0 fprintf(stderr,"**DMALLOC Looking for references:\n"); dmalloc_find_references_to(a); #endif } #endif fprintf(stderr,"**Done looking for references to %p, " "found %"PRINTSIZET"u refs.\n", a, found_ref_count); Pike_in_gc = orig_in_gc; gc_found_place = orig_gc_found_place; if(i) exit_gc(); d_flag=tmp; } void debug_gc_add_extra_ref(void *a) { struct marker *m; if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_add_extra_ref()"); } if (gc_debug) { m = find_marker(a); if ((!m || !(m->flags & GC_PRETOUCHED)) && !safe_debug_findstring((struct pike_string *) a)) gc_fatal(a, 0, "Doing gc_add_extra_ref() on invalid object.\n"); if (!m) m = get_marker(a); } else m = get_marker(a); if (m->flags & GC_GOT_EXTRA_REF) gc_fatal(a, 0, "Thing already got an extra gc ref.\n"); m->flags |= GC_GOT_EXTRA_REF; gc_extra_refs++; add_ref( (struct ref_dummy *)a); } void debug_gc_free_extra_ref(void *a) { struct marker *m; if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_free_extra_ref()"); } if (gc_debug) { m = find_marker(a); if ((!m || !(m->flags & GC_PRETOUCHED)) && !safe_debug_findstring((struct pike_string *) a)) gc_fatal(a, 0, "Doing gc_add_extra_ref() on invalid object.\n"); if (!m) m = get_marker(a); } else m = get_marker(a); if (!(m->flags & GC_GOT_EXTRA_REF)) gc_fatal(a, 0, "Thing haven't got an extra gc ref.\n"); m->flags &= ~GC_GOT_EXTRA_REF; gc_extra_refs--; } int debug_gc_is_referenced(void *a) { struct marker *m; if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_is_referenced()"); } if (!a) Pike_fatal("Got null pointer.\n"); if (Pike_in_gc != GC_PASS_MARK) Pike_fatal("gc_is_referenced() called in invalid gc pass.\n"); if (gc_debug) { m = find_marker(a); if ((!m || !(m->flags & GC_PRETOUCHED)) && !safe_debug_findstring((struct pike_string *) a)) gc_fatal(a, 0, "Doing gc_is_referenced() on invalid object.\n"); if (!m) m = get_marker(a); } else m = get_marker(a); if (m->flags & GC_IS_REFERENCED) gc_fatal(a, 0, "gc_is_referenced() called twice for thing.\n"); m->flags |= GC_IS_REFERENCED; return !(m->flags & GC_NOT_REFERENCED); } int gc_mark_external (void *a, const char *place) { struct marker *m; if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_mark_external()"); } if (!a) Pike_fatal("Got null pointer.\n"); if(Pike_in_gc == GC_PASS_LOCATE) { if(a==check_for) { const char *orig_gc_found_place = gc_found_place; gc_found_place = place; gdb_gc_stop_here(a, 0); gc_found_place = orig_gc_found_place; } return 0; } if (Pike_in_gc != GC_PASS_CHECK) Pike_fatal("gc_mark_external() called in invalid gc pass.\n"); #ifdef DEBUG_MALLOC if (gc_external_refs_zapped) { fprintf (stderr, "One external ref to %p found%s.\n", a, place ? place : ""); if (gc_found_in) describe (gc_found_in); return 0; } #endif m=get_marker(a); m->xrefs++; m->flags|=GC_XREFERENCED; if(Pike_in_gc == GC_PASS_CHECK && (m->refs + m->xrefs > *(INT32 *)a || (m->saved_refs != -1 && m->saved_refs != *(INT32 *)a))) gc_fatal(a, 1, "Ref counts are wrong.\n"); return 0; } #define LOW_CHECK_REC_FRAME(f, file, line) do { \ if (f->rf_flags & GC_FRAME_FREED) \ dloc_gc_fatal (file, line, f->data, 0, \ "Accessing freed gc_stack_frame %p.\n", f); \ if (f->cycle_id->rf_flags & GC_FRAME_FREED) { \ fprintf (stderr, "Cycle id frame %p is freed. It is: ", f->cycle_id); \ describe_rec_frame (f->cycle_id); \ fputc ('\n', stderr); \ dloc_gc_fatal (file, line, f->data, 0, "Cycle id frame is freed.\n"); \ } \ } while (0) static void check_rec_stack_frame (struct gc_rec_frame *f, struct gc_rec_frame *p1, const char *p1n, struct gc_rec_frame *p2, const char *p2n, const char *file, int line) { /* To allow this function to be used after a stack rotation but * before cycle_id markup, there are no checks here for cycle_id * consistency wrt other frames on the rec stack. */ LOW_CHECK_REC_FRAME (f, file, line); if (f->rf_flags & (GC_ON_CYCLE_PIECE_LIST|GC_ON_KILL_LIST)) rec_stack_fatal (f, "err", p1, p1n, p2, p2n, file, line, "Frame %p is not on the rec stack (according to flags).\n", f); if (!f->prev) rec_stack_fatal (f, "err", p1, p1n, p2, p2n, file, line, "Prev pointer not set for rec stack frame %p.\n", f); if (f->prev->next != f) rec_stack_fatal (f, "err", p1, p1n, p2, p2n, file, line, "Rec stack pointers are inconsistent before %p.\n", f); if (f->cycle_id && f->cycle_id->rf_flags & (GC_ON_CYCLE_PIECE_LIST|GC_ON_KILL_LIST)) /* p2 and p2n gets lost here. No bother. */ rec_stack_fatal (f->cycle_id, "cycle id", f, "err", p1, p1n, file, line, "Cycle id frame %p for %p not on the rec stack " "(according to flags).\n", f->cycle_id, f); if ((f->rf_flags & GC_MARK_LIVE) && f != stack_top) rec_stack_fatal (f, "err", p1, p1n, p2, p2n, file, line, "GC_MARK_LIVE frame %p found that " "isn't on the stack top.\n", f); if ((f->rf_flags & GC_PREV_STRONG) && (f->rf_flags & (GC_PREV_WEAK|GC_PREV_BROKEN))) rec_stack_fatal (f, "err", p1, p1n, p2, p2n, file, line, "GC_PREV_STRONG set together with " "GC_PREV_WEAK or GC_PREV_BROKEN in %p.\n", f); if (f->cycle_piece && (!f->cycle_piece->u.last_cycle_piece || f->cycle_piece->u.last_cycle_piece->cycle_piece)) rec_stack_fatal (f, "err", p1, p1n, p2, p2n, file, line, "Bogus last_cycle_piece %p is %p " "in cycle piece top %p in %p.\n", f->cycle_piece->u.last_cycle_piece, f->cycle_piece->u.last_cycle_piece ? f->cycle_piece->u.last_cycle_piece->cycle_piece : NULL, f->cycle_piece, f); } #define CHECK_REC_STACK_FRAME(f) \ do check_rec_stack_frame ((f), NULL, NULL, NULL, NULL, __FILE__, __LINE__); \ while (0) static void check_cycle_piece_frame (struct gc_rec_frame *f, const char *file, int line) { LOW_CHECK_REC_FRAME (f, file, line); if ((f->rf_flags & (GC_ON_CYCLE_PIECE_LIST|GC_ON_KILL_LIST)) != GC_ON_CYCLE_PIECE_LIST) dloc_gc_fatal (file, line, f->data, 0, "Frame is not on a cycle piece list " "(according to flags).\n"); if (f->prev) dloc_gc_fatal (file, line, f->data, 0, "Prev pointer set for frame on cycle piece list.\n"); } #define CHECK_CYCLE_PIECE_FRAME(f) \ do check_cycle_piece_frame ((f), __FILE__, __LINE__); while (0) static void check_kill_list_frame (struct gc_rec_frame *f, const char *file, int line) { LOW_CHECK_REC_FRAME (f, file, line); if ((f->rf_flags & (GC_ON_CYCLE_PIECE_LIST|GC_ON_KILL_LIST)) != GC_ON_KILL_LIST) dloc_gc_fatal (file, line, f->data, 0, "Frame is not on kill list (according to flags).\n"); if (f->prev) dloc_gc_fatal (file, line, f->data, 0, "Prev pointer set for frame on kill list.\n"); } #define CHECK_KILL_LIST_FRAME(f) \ do check_kill_list_frame ((f), __FILE__, __LINE__); while (0) static void check_rec_stack (struct gc_rec_frame *p1, const char *p1n, struct gc_rec_frame *p2, const char *p2n, const char *file, int line) { /* This debug check is disabled during the final cleanup since this * is O(n^2) on the stack size, and the stack gets a lot larger then. */ if (gc_debug && !gc_destruct_everything) { struct gc_rec_frame *l, *last_cycle_id; for (l = &sentinel_frame; l != stack_top;) { l = l->next; check_rec_stack_frame (l, p1, p1n, p2, p2n, file, line); if (l->cycle_id == l) last_cycle_id = l; else if (l->cycle_id != last_cycle_id) rec_stack_fatal (l, "err", p1, p1n, p2, p2n, file, line, "Unexpected cycle id for frame %p.\n", l); else if (l->rf_flags & GC_PREV_WEAK) rec_stack_fatal (l, "err", p1, p1n, p2, p2n, file, line, "Unexpected weak ref before %p inside a cycle.\n", l); if (l->rf_flags & GC_IS_VALID_CP_CYCLE_ID) rec_stack_fatal (l, "err", p1, p1n, p2, p2n, file, line, "Frame %p got stray " "GC_IS_VALID_CP_CYCLE_ID flag.\n", l); if (l->cycle_piece) { struct gc_rec_frame *cp = l->cycle_piece; l->rf_flags |= GC_IS_VALID_CP_CYCLE_ID; while (1) { if (!cp->cycle_id || !(cp->cycle_id->rf_flags & GC_IS_VALID_CP_CYCLE_ID)) rec_stack_fatal (cp, "err", p1, p1n, p2, p2n, file, line, "Unexpected cycle id for frame %p " "on cycle piece list.\n", cp); if (cp->rf_flags & GC_IS_VALID_CP_CYCLE_ID) rec_stack_fatal (cp, "err", p1, p1n, p2, p2n, file, line, "Frame %p got stray " "GC_IS_VALID_CP_CYCLE_ID flag.\n", cp); cp->rf_flags |= GC_IS_VALID_CP_CYCLE_ID; check_cycle_piece_frame (cp, file, line); if (!cp->cycle_piece) break; cp = cp->cycle_piece; } if (l->cycle_piece->u.last_cycle_piece != cp) rec_stack_fatal (l->cycle_piece, "err", p1, p1n, p2, p2n, file, line, "last_cycle_piece is wrong for frame %p, " "expected %p.\n", l->cycle_piece, cp); l->rf_flags &= ~GC_IS_VALID_CP_CYCLE_ID; cp = l->cycle_piece; do { cp->rf_flags &= ~GC_IS_VALID_CP_CYCLE_ID; cp = cp->cycle_piece; } while (cp); } } } } #define CHECK_REC_STACK(p1, p1n, p2, p2n) \ do check_rec_stack ((p1), (p1n), (p2), (p2n), __FILE__, __LINE__); while (0) #else /* !PIKE_DEBUG */ #define CHECK_REC_STACK_FRAME(f) do {} while (0) #define CHECK_CYCLE_PIECE_FRAME(f) do {} while (0) #define CHECK_KILL_LIST_FRAME(f) do {} while (0) #define CHECK_REC_STACK(p1, p1n, p2, p2n) do {} while (0) #endif /* !PIKE_DEBUG */ int gc_do_weak_free(void *a) { struct marker *m; #ifdef PIKE_DEBUG if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_do_weak_free()"); } if (!a) Pike_fatal("Got null pointer.\n"); if (Pike_in_gc != GC_PASS_MARK && Pike_in_gc != GC_PASS_ZAP_WEAK) Pike_fatal("gc_do_weak_free() called in invalid gc pass.\n"); if (gc_debug) { if (!(m = find_marker(a))) gc_fatal(a, 0, "gc_do_weak_free() got unknown object.\n"); } else m = get_marker(a); debug_malloc_touch(a); if (m->weak_refs > m->refs) gc_fatal(a, 0, "More weak references than internal references.\n"); #else m = get_marker(a); #endif if (Pike_in_gc != GC_PASS_ZAP_WEAK) { if (m->weak_refs < 0) goto should_free; } else if (!(m->flags & GC_MARKED)) { #ifdef PIKE_DEBUG if (m->weak_refs <= 0) gc_fatal(a, 0, "Too many weak refs cleared to thing with external " "weak refs.\n"); #endif m->weak_refs--; goto should_free; } return 0; should_free: gc_ext_weak_refs--; #ifdef PIKE_DEBUG m->saved_refs--; m->flags |= GC_WEAK_FREED; #endif if (*(INT32 *) a == 1) { /* Make sure the thing doesn't run out of refs, since we can't * handle cascading frees now. We'll do it in the free pass * instead. */ gc_add_extra_ref(a); m->flags |= GC_GOT_DEAD_REF; #ifdef PIKE_DEBUG delayed_freed++; #endif } return 1; } void gc_delayed_free(void *a, int type) { struct marker *m; #ifdef PIKE_DEBUG if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_delayed_free()"); } if (Pike_in_gc != GC_PASS_MARK && Pike_in_gc != GC_PASS_CYCLE && Pike_in_gc != GC_PASS_ZAP_WEAK) Pike_fatal("gc_delayed_free() called in invalid gc pass.\n"); if (gc_debug) { if (!(m = find_marker(a))) gc_fatal(a, 0, "gc_delayed_free() got unknown object (missed by pretouch pass).\n"); } else m = get_marker(a); if (*(INT32 *) a != 1) Pike_fatal("gc_delayed_free() called for thing that haven't got a single ref.\n"); debug_malloc_touch(a); delayed_freed++; #else m = get_marker(a); #endif if (m->flags & GC_MARKED) { /* Note that we can get marked things here, e.g. if the index in a * mapping with weak indices is removed in the zap weak pass, the * value will be zapped too, but it will still have a mark from * the mark pass. This means that the stuff referenced by the * value will only be refcount garbed, which can leave cyclic * garbage for the next gc round. * * Since the value has been marked we won't find it in the free * pass, so we have to keep special track of it. :P */ struct free_extra_frame *l = alloc_free_extra_frame(); l->data = a; l->type = type; l->next = free_extra_list; free_extra_list = l; } gc_add_extra_ref(a); m->flags |= GC_GOT_DEAD_REF; } int gc_mark(void *a) { struct marker *m; #ifdef PIKE_DEBUG if (Pike_in_gc == GC_PASS_ZAP_WEAK && !find_marker (a)) gc_fatal (a, 0, "gc_mark() called for for thing without marker " "in zap weak pass.\n"); #endif m = get_marker (a); /* Note: m->refs and m->xrefs are useless already here due to how * gc_free_(short_)svalue works. */ #ifdef PIKE_DEBUG if (gc_is_watching && m && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_mark()"); } if (!a) Pike_fatal("Got null pointer.\n"); if (Pike_in_gc != GC_PASS_MARK && Pike_in_gc != GC_PASS_ZAP_WEAK) Pike_fatal("GC mark attempted in invalid pass.\n"); if (!*(INT32 *) a) gc_fatal(a, 0, "Marked a thing without refs.\n"); if (m->weak_refs < 0) gc_fatal(a, 0, "Marking thing scheduled for weak free.\n"); #endif if (Pike_in_gc == GC_PASS_ZAP_WEAK) { /* Things are visited in the zap weak pass through the mark * functions to free refs to internal things that only got weak * external references. That happens only when a thing also have * internal cyclic nonweak refs. */ #ifdef PIKE_DEBUG if (!(m->flags & GC_MARKED)) gc_fatal(a, 0, "gc_mark() called for thing in zap weak pass " "that wasn't marked before.\n"); #endif if (m->flags & GC_FREE_VISITED) { debug_malloc_touch (a); return 0; } else { debug_malloc_touch (a); m->flags |= GC_FREE_VISITED; return 1; } } else if (m->flags & GC_MARKED) { debug_malloc_touch (a); #ifdef PIKE_DEBUG if (m->weak_refs != 0) gc_fatal (a, 0, "weak_refs changed in marker " "already visited by gc_mark().\n"); #endif return 0; } else { debug_malloc_touch (a); if (m->weak_refs) { gc_ext_weak_refs -= m->weak_refs; m->weak_refs = 0; } m->flags = (m->flags & ~GC_NOT_REFERENCED) | GC_MARKED; DO_IF_DEBUG(marked++); return 1; } } void gc_move_marker (void *old, void *new) { struct marker *m = find_marker (old); #ifdef PIKE_DEBUG if (!Pike_in_gc || Pike_in_gc >= GC_PASS_FREE) Pike_fatal ("gc move mark attempted in invalid pass.\n"); if (!old) Pike_fatal ("Got null pointer in old.\n"); if (!new) Pike_fatal ("Got null pointer in new.\n"); if (!m) Pike_fatal ("Have no marker for old block %p.\n", old); if (find_marker (new)) Pike_fatal ("New block %p already got a marker.\n", new); #endif move_marker (m, debug_malloc_pass (new)); } PMOD_EXPORT void gc_cycle_enqueue(gc_cycle_check_cb *checkfn, void *data, int weak) { struct link_frame *l = alloc_link_frame(); #ifdef PIKE_DEBUG { struct marker *m; if (gc_is_watching && (m = find_marker(data)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_cycle_enqueue()"); } } if (Pike_in_gc != GC_PASS_CYCLE) gc_fatal(data, 0, "Use of the gc frame stack outside the cycle check pass.\n"); if (stack_top == &sentinel_frame) gc_fatal (data, 0, "No thing on rec stack to follow links from.\n"); #endif l->data = data; l->checkfn = checkfn; l->weak = weak; l->prev = stack_top->u.link_top; #ifdef GC_STACK_DEBUG fprintf (stderr, "push link %p [%p in %p]: ", l, stack_top->u.link_top, stack_top); describe_link_frame (l); fputc('\n', stderr); #endif stack_top->u.link_top = l; } static struct gc_rec_frame *gc_cycle_enqueue_rec (void *data) { struct gc_rec_frame *r = alloc_gc_rec_frame(); #ifdef PIKE_DEBUG if (Pike_in_gc != GC_PASS_CYCLE) gc_fatal(data, 0, "Use of the gc frame stack outside the cycle check pass.\n"); r->next = (struct gc_rec_frame *) (ptrdiff_t) -1; #endif r->data = data; r->u.link_top = NULL; r->prev = stack_top; r->cycle_id = r; r->cycle_piece = NULL; #ifdef GC_STACK_DEBUG fprintf (stderr, "push rec %p [%p]: ", r, stack_top); describe_rec_frame (r); fputc('\n', stderr); #endif stack_top->next = r; stack_top = r; return r; } void gc_cycle_run_queue() { #ifdef PIKE_DEBUG if (Pike_in_gc != GC_PASS_CYCLE) Pike_fatal("Use of the gc frame stack outside the cycle check pass.\n"); #endif while (stack_top != &sentinel_frame) { while (stack_top->u.link_top) { struct link_frame l = *stack_top->u.link_top; #ifdef GC_STACK_DEBUG fprintf (stderr, "pop link %p [%p in %p]: ", stack_top->u.link_top, l.prev, stack_top); describe_link_frame (stack_top->u.link_top); fputc ('\n', stderr); #endif really_free_link_frame (stack_top->u.link_top); stack_top->u.link_top = l.prev; l.checkfn (l.data, l.weak); /* Might change stack_top. */ } #ifdef GC_STACK_DEBUG fprintf (stderr, "pop rec %p [%p]: ", stack_top, stack_top->prev); describe_rec_frame (stack_top); fputc ('\n', stderr); #endif CHECK_REC_STACK_FRAME (stack_top); #ifdef PIKE_DEBUG { struct gc_rec_frame *old_stack_top = stack_top; gc_cycle_pop(); if (stack_top == old_stack_top) fatal ("gc_cycle_pop didn't pop the stack.\n"); } #else gc_cycle_pop(); #endif } } #ifdef GC_CYCLE_DEBUG static int gc_cycle_indent = 0; #define CYCLE_DEBUG_MSG(REC, TXT) do { \ struct gc_rec_frame *r_ = (REC); \ fprintf (stderr, "%*s%-35s %p [%p] ", gc_cycle_indent, "", \ (TXT), r_ ? r_->data : NULL, stack_top->data); \ if (r_) describe_rec_frame (r_); \ putc ('\n', stderr); \ } while (0) #else #define CYCLE_DEBUG_MSG(REC, TXT) do {} while (0) #endif static struct gc_rec_frame *rotate_rec_stack (struct gc_rec_frame *beg, struct gc_rec_frame *pos) /* Performs a rotation of the recursion stack so the part from pos * down to the end gets before the part from beg down to pos. The beg * position might be moved further back the list to avoid breaking * strong link sequences. Returns the actual beg position. Example: * * strong * a1 <=> ... <=> a2 <=> b1 <*> b2 <=> ... <=> b3 <=> c1 <=> ... <=> c2 * ^ beg ^ pos * * becomes * * broken strong * a1 <=> ... <=> a2 <#> c1 <=> ... <=> c2 <=> b1 <*> b2 <=> ... <=> b3 * ^ pos ^ ^ beg * returned * * Note: The part from pos down to the end is assumed to not contain * any weak refs. (If it does they must be cleared, unless the link * before beg is weak.) */ { CYCLE_DEBUG_MSG (beg, "> rotate_rec_stack, requested beg"); #ifdef PIKE_DEBUG if (Pike_in_gc != GC_PASS_CYCLE) Pike_fatal("Use of the gc frame stack outside the cycle check pass.\n"); CHECK_REC_STACK_FRAME (beg); CHECK_REC_STACK_FRAME (pos); if (beg == pos) gc_fatal (beg->data, 0, "Cycle already broken at requested position.\n"); #endif #ifdef GC_STACK_DEBUG fprintf(stderr,"Stack before:\n"); describe_rec_stack (beg, "beg", pos, "pos", NULL, NULL); #endif /* Always keep chains of strong refs continuous, or else we risk * breaking the order in a later rotation. */ for (; beg->rf_flags & GC_PREV_STRONG; beg = beg->prev) CYCLE_DEBUG_MSG (beg, "> rotate_rec_stack, skipping strong"); #ifdef PIKE_DEBUG if (beg == &sentinel_frame) fatal ("Strong ref chain ended up off stack.\n"); #endif CYCLE_DEBUG_MSG (beg, "> rotate_rec_stack, actual beg"); { struct gc_rec_frame *new_stack_top = pos->prev; beg->prev->next = pos; pos->prev = beg->prev; stack_top->next = beg; beg->prev = stack_top; stack_top = new_stack_top; #ifdef PIKE_DEBUG stack_top->next = (struct gc_rec_frame *) (ptrdiff_t) -1; #endif } #ifdef PIKE_DEBUG frame_rot++; #endif pos->rf_flags |= GC_PREV_BROKEN; #ifdef GC_STACK_DEBUG fprintf(stderr,"Stack after:\n"); describe_rec_stack (beg, "ret", pos, "pos", NULL, NULL); #endif return beg; } int gc_cycle_push(void *data, struct marker *m, int weak) { struct marker *pm; #ifdef PIKE_DEBUG if (gc_is_watching && m && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_cycle_push()"); } debug_malloc_touch (data); if (!data) Pike_fatal ("Got null pointer.\n"); if (m->data != data) Pike_fatal ("Got wrong marker.\n"); if (Pike_in_gc != GC_PASS_CYCLE) Pike_fatal("GC cycle push attempted in invalid pass.\n"); if (gc_debug && !(m->flags & GC_PRETOUCHED)) gc_fatal (data, 0, "gc_cycle_push() called for untouched thing.\n"); if (!gc_destruct_everything) { if ((!(m->flags & GC_NOT_REFERENCED) || m->flags & GC_MARKED) && *(INT32 *) data) gc_fatal (data, 1, "Got a referenced marker to gc_cycle_push.\n"); if (m->flags & GC_XREFERENCED) gc_fatal (data, 1, "Doing cycle check in externally referenced thing " "missed in mark pass.\n"); } if (weak && stack_top == &sentinel_frame) gc_fatal (data, 1, "weak is %d when stack is empty.\n", weak); if (gc_debug > 1) { struct array *a; struct object *o; struct program *p; struct mapping *m; struct multiset *l; for(a = gc_internal_array; a; a = a->next) if(a == (struct array *) data) goto on_gc_internal_lists; for(o = gc_internal_object; o; o = o->next) if(o == (struct object *) data) goto on_gc_internal_lists; for(p = gc_internal_program; p; p = p->next) if(p == (struct program *) data) goto on_gc_internal_lists; for(m = gc_internal_mapping; m; m = m->next) if(m == (struct mapping *) data) goto on_gc_internal_lists; for(l = gc_internal_multiset; l; l = l->next) if(l == (struct multiset *) data) goto on_gc_internal_lists; gc_fatal (data, 0, "gc_cycle_check() called for thing not on gc_internal lists.\n"); on_gc_internal_lists: ; /* We must have a least one expression after a label! - Hubbe */ } #endif if (stack_top->rf_flags & GC_MARK_LIVE) { /* Only recurse through things already handled; we'll get to the * other later in the normal recursion. */ if (m->flags & GC_CYCLE_CHECKED && !(m->flags & GC_LIVE)) { CYCLE_DEBUG_MSG (m->frame, "gc_cycle_push, mark live"); goto mark_live; } CYCLE_DEBUG_MSG (m->frame, "gc_cycle_push, no mark live"); return 0; } if (stack_top == &sentinel_frame) pm = NULL; else { pm = find_marker (stack_top->data); #ifdef PIKE_DEBUG if (!pm) gc_fatal (stack_top->data, 0, "No marker for thing on top of the stack.\n"); #endif } #ifdef PIKE_DEBUG if (weak < 0 && stack_top->rf_flags & GC_FOLLOWED_NONSTRONG) gc_fatal (data, 0, "Followed strong link too late.\n"); if (weak >= 0) stack_top->rf_flags |= GC_FOLLOWED_NONSTRONG; #endif if (m->frame) { /* A cyclic ref or a ref to something on the kill list is found. */ struct gc_rec_frame *cycle_frame = m->frame; if (cycle_frame->rf_flags & GC_ON_KILL_LIST) CYCLE_DEBUG_MSG (cycle_frame, "gc_cycle_push, ref to kill list"); else if (cycle_frame == stack_top) CYCLE_DEBUG_MSG (cycle_frame, "gc_cycle_push, self-ref"); else if (weak > 0) /* Ignore weak refs since they always are eligible to be broken anyway. */ CYCLE_DEBUG_MSG (cycle_frame, "gc_cycle_push, weak cyclic ref"); else { struct gc_rec_frame *weakly_refd = NULL; struct gc_rec_frame *brokenly_refd = NULL; struct gc_rec_frame *nonstrongly_refd = NULL; #ifdef PIKE_DEBUG if (stack_top == &sentinel_frame) gc_fatal (data, 0, "Cyclic ref involves dummy sentinel frame.\n"); CHECK_REC_STACK_FRAME (stack_top); #endif CYCLE_DEBUG_MSG (cycle_frame, "gc_cycle_push, cyclic ref"); /* Find the corresponding frame still on the stack and compress * indirect cycle_id links. */ { struct gc_rec_frame *r; for (r = cycle_frame; !r->prev; r = r->cycle_id) CHECK_CYCLE_PIECE_FRAME (r); while (cycle_frame != r) { struct gc_rec_frame *next = cycle_frame->cycle_id; cycle_frame->cycle_id = r; cycle_frame = next; } CHECK_REC_STACK_FRAME (cycle_frame); } if (!weak) { struct gc_rec_frame *r; CYCLE_DEBUG_MSG (cycle_frame, "gc_cycle_push, search normal"); /* Find the last weakly linked thing and the last thing whose * normal ref already has been broken. */ for (r = stack_top; r != cycle_frame; r = r->prev) { CHECK_REC_STACK_FRAME (r); DO_IF_DEBUG (link_search++); if (r->rf_flags & GC_PREV_WEAK) { CYCLE_DEBUG_MSG (r, "> gc_cycle_push, found weak"); weakly_refd = r; break; } if (!brokenly_refd && (r->rf_flags & GC_PREV_BROKEN)) { CYCLE_DEBUG_MSG (r, "> gc_cycle_push, found broken"); brokenly_refd = r; } else CYCLE_DEBUG_MSG (r, "> gc_cycle_push, search"); } } else if (weak < 0) { struct gc_rec_frame *r; CYCLE_DEBUG_MSG (cycle_frame, "gc_cycle_push, search strong"); /* Find the last weakly linked thing and the last one which * isn't strongly linked. */ for (r = stack_top; r != cycle_frame; r = r->prev) { CHECK_REC_STACK_FRAME (r); DO_IF_DEBUG (link_search++); if (r->rf_flags & GC_PREV_WEAK) { CYCLE_DEBUG_MSG (r, "> gc_cycle_push, found weak"); weakly_refd = r; break; } if (!nonstrongly_refd && !(r->rf_flags & GC_PREV_STRONG)) { nonstrongly_refd = r; CYCLE_DEBUG_MSG (r, "> gc_cycle_push, found nonstrong"); } if (!brokenly_refd && (r->rf_flags & GC_PREV_BROKEN)) { CYCLE_DEBUG_MSG (r, "> gc_cycle_push, found broken"); brokenly_refd = r; } #ifdef GC_CYCLE_DEBUG else if (r != nonstrongly_refd) CYCLE_DEBUG_MSG (r, "> gc_cycle_push, search"); #endif } #ifdef PIKE_DEBUG if (weak && r == cycle_frame && !nonstrongly_refd) { fprintf(stderr, "Only strong links in cycle:\n"); for (r = cycle_frame;; r = r->next) { describe (r->data); locate_references (r->data); if (r == stack_top) break; fprintf(stderr, "========= next =========\n"); } gc_fatal(0, 0, "Only strong links in cycle.\n"); } #endif } if (weakly_refd) { /* The backward link is normal or strong and there are one or * more weak links in the cycle. Let's break it at the last * one (to avoid having to clobber the others after the * rotation). */ CYCLE_DEBUG_MSG (weakly_refd, "gc_cycle_push, weak break"); /* If the backward link points into a cycle, we rotate the * whole cycle up the stack. See the "cycle checking" blurb * above for rationale. */ rotate_rec_stack (cycle_frame->cycle_id, weakly_refd); CHECK_REC_STACK (cycle_frame, "cycle_frame", weakly_refd, "weakly_refd"); } else { struct gc_rec_frame *cycle_id = cycle_frame->cycle_id; struct gc_rec_frame *break_pos; if (brokenly_refd) { /* Found a link that already has been broken once, so we * prefer to break at it again. */ CYCLE_DEBUG_MSG (brokenly_refd, "gc_cycle_push, break at broken"); break_pos = brokenly_refd; } else if (!weak) { CYCLE_DEBUG_MSG (cycle_frame, "gc_cycle_push, no break spot found"); break_pos = NULL; } else { /* weak < 0 */ /* The backward link is strong. Must break the cycle at the * last nonstrong link. */ CYCLE_DEBUG_MSG (nonstrongly_refd, "gc_cycle_push, nonstrong break"); break_pos = nonstrongly_refd; } if (break_pos) { struct gc_rec_frame *rot_beg; rot_beg = rotate_rec_stack (cycle_frame, break_pos); rot_beg->rf_flags &= ~(GC_PREV_WEAK|GC_PREV_BROKEN); if (weak >= 0) rot_beg->rf_flags |= GC_PREV_STRONG; if (rot_beg->cycle_id != break_pos->prev->cycle_id) /* Ensure that the cycle id frame is kept deepest in the * stack: Since there's no already marked cycle that * continues past the beginning of the rotated portion * (rot_beg and break_pos->prev were previously next to * each other), break_pos is now the deepest frame in the * cycle. */ cycle_id = break_pos; } /* Mark the cycle. NB: This causes O(n^2) complexity for some * kinds of data structures. */ CHECK_REC_STACK_FRAME (cycle_id); { struct gc_rec_frame *r, *bottom = break_pos ? break_pos : cycle_frame; CYCLE_DEBUG_MSG (cycle_id, "gc_cycle_push, cycle"); for (r = stack_top;; r = r->prev) { r->cycle_id = cycle_id; CHECK_REC_STACK_FRAME (r); CYCLE_DEBUG_MSG (r, "> gc_cycle_push, mark cycle 1"); if (r == bottom) break; } } CHECK_REC_STACK (cycle_frame, "cycle_frame", break_pos, "break_pos"); } } } else if (!(m->flags & GC_CYCLE_CHECKED)) { struct gc_rec_frame *r; #ifdef PIKE_DEBUG cycle_checked++; if (m->frame) gc_fatal (data, 0, "Marker already got a frame.\n"); #endif m->flags |= GC_CYCLE_CHECKED | (pm ? pm->flags & GC_LIVE : 0); m->frame = r = gc_cycle_enqueue_rec (data); debug_malloc_touch (data); if (weak) { if (weak > 0) r->rf_flags = GC_PREV_WEAK; else r->rf_flags = GC_PREV_STRONG; } else r->rf_flags = 0; #ifdef GC_CYCLE_DEBUG if (weak > 0) CYCLE_DEBUG_MSG (r, "gc_cycle_push, recurse weak"); else if (weak < 0) CYCLE_DEBUG_MSG (r, "gc_cycle_push, recurse strong"); else CYCLE_DEBUG_MSG (r, "gc_cycle_push, recurse"); gc_cycle_indent += 2; #endif CHECK_REC_STACK (NULL, NULL, NULL, NULL); return 1; } /* Should normally not recurse now, but got to do that anyway if we * must propagate GC_LIVE flags. */ if (!pm || !(pm->flags & GC_LIVE) || m->flags & GC_LIVE) { CYCLE_DEBUG_MSG (m->frame ? m->frame : NULL, "gc_cycle_push, no recurse"); return 0; } /* Initialize mark live recursion. */ gc_cycle_enqueue_rec (NULL)->rf_flags = GC_MARK_LIVE; #ifdef GC_CYCLE_DEBUG CYCLE_DEBUG_MSG (m->frame ? m->frame : NULL, "gc_cycle_push, mark live begins"); gc_cycle_indent += 2; #endif mark_live: #ifdef PIKE_DEBUG if (m->flags & GC_LIVE) Pike_fatal("Shouldn't mark live recurse when there's nothing to do.\n"); #endif m->flags |= GC_LIVE; debug_malloc_touch (data); if (m->flags & GC_GOT_DEAD_REF) { /* A thing previously popped as dead is now being marked live. * Have to remove the extra ref added by gc_cycle_pop(). */ gc_free_extra_ref (data); if (!sub_ref ((struct ref_dummy *) data)) { #ifdef PIKE_DEBUG gc_fatal (data, 0, "Thing got zero refs after removing the dead gc ref.\n"); #endif } } /* Visit links without pushing a rec frame. */ #ifdef PIKE_DEBUG mark_live++; #endif return 1; } static void gc_cycle_pop() { #ifdef PIKE_DEBUG if (Pike_in_gc != GC_PASS_CYCLE) Pike_fatal("GC cycle pop attempted in invalid pass.\n"); if (stack_top->u.link_top) gc_fatal (stack_top->data, 0, "Link list not empty for popped rec frame.\n"); #endif #ifdef GC_CYCLE_DEBUG gc_cycle_indent -= 2; #endif if (stack_top->rf_flags & GC_MARK_LIVE) { struct gc_rec_frame *r = stack_top->prev; CYCLE_DEBUG_MSG (stack_top, "gc_cycle_pop, mark live ends"); really_free_gc_rec_frame (stack_top); stack_top = r; } else { struct gc_rec_frame *popped = stack_top; #ifdef PIKE_DEBUG { void *data = popped->data; struct marker *m = find_marker (data); if (gc_is_watching && m && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_cycle_pop()"); } if (!(m->flags & GC_CYCLE_CHECKED)) gc_fatal (data, 0, "Marker being popped doesn't have GC_CYCLE_CHECKED.\n"); if (!gc_destruct_everything) { if ((!(m->flags & GC_NOT_REFERENCED) || m->flags & GC_MARKED) && *(INT32 *) data) gc_fatal (data, 1, "Got a referenced marker to gc_cycle_pop.\n"); if (m->flags & GC_XREFERENCED) gc_fatal (data, 1, "Doing cycle check in externally referenced thing " "missed in mark pass.\n"); } if (popped->next != (struct gc_rec_frame *) (ptrdiff_t) -1) gc_fatal (data, 0, "Popped rec frame got stuff in the next pointer.\n"); } #endif stack_top = popped->prev; #ifdef PIKE_DEBUG if (stack_top != &sentinel_frame) CHECK_REC_STACK_FRAME (stack_top); CHECK_REC_STACK_FRAME (popped); #endif popped->prev = NULL; if (popped->cycle_id != popped) { /* Part of a cycle that extends further back - move to the cycle * piece list of the previous frame. */ struct gc_rec_frame *this_list_last = popped->cycle_piece ? popped->cycle_piece->u.last_cycle_piece : popped; #ifdef PIKE_DEBUG if (this_list_last->cycle_piece) gc_fatal (this_list_last->data, 0, "This frame should be last on the cycle piece list.\n"); popped->rf_flags |= GC_ON_CYCLE_PIECE_LIST; CHECK_CYCLE_PIECE_FRAME (this_list_last); #endif CYCLE_DEBUG_MSG (popped, "gc_cycle_pop, keep cycle piece"); if (!stack_top->cycle_piece) popped->u.last_cycle_piece = this_list_last; else { /* Link in the popped frame and its cycle piece list before * the one that the previous frame has. */ struct gc_rec_frame *up_list_first = stack_top->cycle_piece; struct gc_rec_frame *up_list_last = up_list_first->u.last_cycle_piece; #ifdef PIKE_DEBUG CHECK_CYCLE_PIECE_FRAME (up_list_last); if (up_list_last->cycle_piece) gc_fatal (up_list_last->data, 0, "This frame should be last on the cycle piece list.\n"); #endif CYCLE_DEBUG_MSG (up_list_first, "> gc_cycle_pop, inserted before"); this_list_last->cycle_piece = up_list_first; popped->u.last_cycle_piece = up_list_last; } stack_top->cycle_piece = popped; popped->cycle_id = stack_top; #ifdef PIKE_DEBUG popped->next = (void *) (ptrdiff_t) -1; #endif CHECK_CYCLE_PIECE_FRAME (popped); CHECK_REC_STACK_FRAME (stack_top); } else { /* Free or move to the kill list the popped frame and its cycle * piece list. */ struct gc_rec_frame **kill_list_ptr = &kill_list; struct gc_rec_frame *cycle_id = NULL; #ifdef PIKE_DEBUG { struct gc_rec_frame *r; for (r = popped->cycle_piece; r; r = r->cycle_piece) /* Can't do this while the list is being freed below. */ CHECK_CYCLE_PIECE_FRAME (r); } #endif CYCLE_DEBUG_MSG (popped, "gc_cycle_pop, popping cycle"); do { struct marker *m = find_marker (popped->data); struct gc_rec_frame *next = popped->cycle_piece; if (m->flags & GC_LIVE_OBJ) { /* Move to the kill list. */ #ifdef PIKE_DEBUG popped->rf_flags &= ~GC_ON_CYCLE_PIECE_LIST; popped->cycle_piece = popped->u.last_cycle_piece = (struct gc_rec_frame *) (ptrdiff_t) -1; #endif popped->next = *kill_list_ptr; *kill_list_ptr = popped; kill_list_ptr = &popped->next; popped->rf_flags |= GC_ON_KILL_LIST; /* Ensure that the frames on the kill list have a valid * cycle id frame and that every frame is linked directly to * it. This is only for the sake of warn_bad_cycles. */ if (!cycle_id) cycle_id = popped; popped->cycle_id = cycle_id; /* This extra ref is taken away in the kill pass. Don't add one * if it got an extra ref already due to weak free. */ if (!(m->flags & GC_GOT_DEAD_REF)) gc_add_extra_ref (popped->data); CHECK_KILL_LIST_FRAME (popped); CYCLE_DEBUG_MSG (popped, "> gc_cycle_pop, move to kill list"); } else { if (!(m->flags & GC_LIVE)) { /* Add an extra ref which is taken away in the free pass. This * is done to not refcount garb the cycles themselves * recursively, which in bad cases can consume a lot of C * stack. */ if (!(m->flags & GC_GOT_DEAD_REF)) { gc_add_extra_ref (popped->data); m->flags |= GC_GOT_DEAD_REF; } } #ifdef PIKE_DEBUG else if (m->flags & GC_GOT_DEAD_REF) gc_fatal (popped->data, 0, "Didn't expect a dead extra ref.\n"); #endif CYCLE_DEBUG_MSG (popped, "> gc_cycle_pop, free"); m->frame = NULL; really_free_gc_rec_frame (popped); } popped = next; } while (popped); } } #ifdef PIKE_DEBUG stack_top->next = (struct gc_rec_frame *) (ptrdiff_t) -1; #endif } void do_gc_recurse_svalues(struct svalue *s, int num) { gc_recurse_svalues(s, num); } void do_gc_recurse_short_svalue(union anything *u, int type) { gc_recurse_short_svalue(u, type); } int gc_do_free(void *a) { struct marker *m; #ifdef PIKE_DEBUG if (gc_is_watching && (m = find_marker(a)) && m->flags & GC_WATCHED) { /* This is useful to set breakpoints on. */ gc_watched_found (m, "gc_do_free()"); } if (!a) Pike_fatal("Got null pointer.\n"); if (Pike_in_gc != GC_PASS_FREE) Pike_fatal("gc free attempted in invalid pass.\n"); #endif m=find_marker(debug_malloc_pass(a)); if (!m) return 0; /* Object created after cycle pass. */ if (gc_destruct_everything) { /* We don't actually free much in this mode, just destruct * objects. So when we normally would return nonzero we just * remove the extra ref again. */ if (!(m->flags & GC_LIVE)) { if (*(INT32 *) a == 1) return 1; else { gc_free_extra_ref (a); sub_ref ((struct ref_dummy *) a); } } return 0; } #ifdef PIKE_DEBUG if (*(INT32 *) a > !!(m->flags & GC_GOT_EXTRA_REF)) { if (!gc_destruct_everything && (!(m->flags & GC_NOT_REFERENCED) || m->flags & GC_MARKED)) gc_fatal(a, 0, "gc_do_free() called for referenced thing.\n"); if (gc_debug && (m->flags & (GC_PRETOUCHED|GC_MARKED|GC_IS_REFERENCED)) == GC_PRETOUCHED) gc_fatal(a, 0, "gc_do_free() called without prior call to " "gc_mark() or gc_is_referenced().\n"); } if(!gc_destruct_everything && (m->flags & (GC_MARKED|GC_XREFERENCED)) == GC_XREFERENCED) gc_fatal(a, 1, "Thing with external reference missed in gc mark pass.\n"); if ((m->flags & (GC_DO_FREE|GC_LIVE)) == GC_LIVE) live_ref++; m->flags |= GC_DO_FREE; #endif return !(m->flags & GC_LIVE); } static void free_obj_arr(void *oa) { struct array *obj_arr = *((struct array **)oa); if (obj_arr) free_array(obj_arr); free(oa); } /*! @class MasterObject */ /*! @decl void runtime_warning(string subsystem, string msg, mixed|void data) *! *! Called by the Pike runtime to warn about data inconsistencies. *! *! @param subsystem *! Runtime subsystem where the warning was generated. *! Currently the following subsystems may call this function: *! @string *! @value "gc" *! The garbage collector. *! @endstring *! *! @param msg *! Warning message. *! Currently the following messages may be generated: *! @string *! @value "bad_cycle" *! A cycle where the destruction order isn't deterministic *! was detected by the garbage collector. *! *! @[data] will in this case contain an array of the elements *! in the cycle. *! @endstring *! *! @param data *! Optional data that further describes the warning specified by @[msg]. */ /*! @endclass */ static void warn_bad_cycles(void) { /* The reason for the extra level of indirection, is that it might * be clobbered by the longjump() in SET_ONERROR otherwise. * (On some architectures longjump() might restore obj_arr's original * value (eg if obj_arr is in a register)). */ struct array **obj_arr_ = (struct array **)xalloc(sizeof(struct array *)); ONERROR tmp; *obj_arr_ = NULL; SET_ONERROR(tmp, free_obj_arr, obj_arr_); #if 0 { struct gc_pop_frame *p; unsigned cycle = 0; *obj_arr_ = allocate_array(0); for (p = kill_list; p;) { if ((cycle = p->cycle)) { push_object((struct object *) p->data); dmalloc_touch_svalue(Pike_sp-1); *obj_arr_ = append_array(*obj_arr_, --Pike_sp); } p = p->next; if (p ? ((unsigned)(p->cycle != cycle)) : cycle) { if ((*obj_arr_)->size >= 2) { push_constant_text("gc"); push_constant_text("bad_cycle"); push_array(*obj_arr_); *obj_arr_ = 0; SAFE_APPLY_MASTER("runtime_warning", 3); pop_stack(); *obj_arr_ = allocate_array(0); } else *obj_arr_ = resize_array(*obj_arr_, 0); } if (!p) break; } } #endif CALL_AND_UNSET_ONERROR(tmp); } size_t do_gc(void *ignored, int explicit_call) { ALLOC_COUNT_TYPE start_allocs; size_t start_num_objs, unreferenced; cpu_time_t gc_start_time; ptrdiff_t objs, pre_kill_objs; #if defined (PIKE_DEBUG) || defined (DO_PIKE_CLEANUP) unsigned destroy_count; #endif #ifdef PIKE_DEBUG unsigned obj_count; ONERROR uwp; #endif if(Pike_in_gc) return 0; if (gc_enabled <= 0 && (gc_enabled < 0 || !explicit_call)) { num_allocs = 0; alloc_threshold = GC_MAX_ALLOC_THRESHOLD; if (gc_evaluator_callback) { remove_callback (gc_evaluator_callback); gc_evaluator_callback = NULL; } return 0; } #ifdef DEBUG_MALLOC if(debug_options & GC_RESET_DMALLOC) reset_debug_malloc(); #endif init_gc(); gc_generation++; Pike_in_gc=GC_PASS_PREPARE; gc_start_time = get_cpu_time(); gc_debug = d_flag; #ifdef PIKE_DEBUG SET_ONERROR(uwp, fatal_on_error, "Shouldn't get an exception inside the gc.\n"); if (gc_is_watching) fprintf(stderr, "## Doing gc while watching for %d things.\n", gc_is_watching); #endif destruct_objects_to_destruct(); if(gc_evaluator_callback) { remove_callback(gc_evaluator_callback); gc_evaluator_callback=0; } objs=num_objects; if(GC_VERBOSE_DO(1 ||) gc_trace) { if (gc_destruct_everything) fprintf (stderr, "Destructing all objects... "); else fprintf(stderr,"Garbage collecting... "); GC_VERBOSE_DO(fprintf(stderr, "\n")); } #ifdef PIKE_DEBUG if(num_objects < 0) Pike_fatal("Panic, less than zero objects!\n"); #endif last_gc=TIME(0); start_num_objs = num_objects; start_allocs = num_allocs; num_allocs = 0; /* Object alloc/free and any reference changes are disallowed now. */ #ifdef PIKE_DEBUG delayed_freed = weak_freed = checked = marked = cycle_checked = live_ref = 0; mark_live = frame_rot = link_search = 0; #endif rec_frames = link_frames = free_extra_frames = 0; max_rec_frames = max_link_frames = 0; if (gc_debug) { unsigned n; Pike_in_gc = GC_PASS_PRETOUCH; n = gc_touch_all_arrays(); n += gc_touch_all_multisets(); n += gc_touch_all_mappings(); n += gc_touch_all_programs(); n += gc_touch_all_objects(); #ifdef PIKE_DEBUG gc_touch_all_strings(); #endif if (n != (unsigned) num_objects && !got_unlinked_things) Pike_fatal("Object count wrong before gc; expected %d, got %d.\n", num_objects, n); GC_VERBOSE_DO(fprintf(stderr, "| pretouch: %u things\n", n)); } /* First we count internal references */ Pike_in_gc=GC_PASS_CHECK; gc_ext_weak_refs = 0; #ifdef PIKE_DEBUG mark_externals(); #endif call_callback(& gc_callbacks, NULL); ACCEPT_UNFINISHED_TYPE_FIELDS { gc_check_all_arrays(); gc_check_all_multisets(); gc_check_all_mappings(); gc_check_all_programs(); gc_check_all_objects(); #if defined (PIKE_DEBUG) || defined (DO_PIKE_CLEANUP) gc_check_all_types(); #endif } END_ACCEPT_UNFINISHED_TYPE_FIELDS; GC_VERBOSE_DO(fprintf(stderr, "| check: %u references in %d things, " "counted %"PRINTSIZET"u weak refs\n", checked, num_objects, gc_ext_weak_refs)); /* Object alloc/free are still disallowed, but refs might be lowered * by gc_free_(short_)svalue. */ Pike_in_gc=GC_PASS_MARK; /* Anything after and including gc_internal_* in the linked lists * are considered to lack external references. The mark pass move * externally referenced things in front of these pointers. */ gc_internal_array = first_array; gc_internal_multiset = first_multiset; gc_internal_mapping = first_mapping; gc_internal_program = first_program; gc_internal_object = first_object; if (gc_destruct_everything) { GC_VERBOSE_DO(fprintf(stderr, "| mark pass skipped - will destruct all objects\n")); } else { /* Next we mark anything with external references. Note that we can * follow the same reference several times, e.g. with shared mapping * data blocks. */ ACCEPT_UNFINISHED_TYPE_FIELDS { gc_mark_all_arrays(); gc_mark_run_queue(); gc_mark_all_multisets(); gc_mark_run_queue(); gc_mark_all_mappings(); gc_mark_run_queue(); gc_mark_all_programs(); gc_mark_run_queue(); gc_mark_all_objects(); gc_mark_run_queue(); #ifdef PIKE_DEBUG if(gc_debug) gc_mark_all_strings(); #endif /* PIKE_DEBUG */ } END_ACCEPT_UNFINISHED_TYPE_FIELDS; GC_VERBOSE_DO(fprintf(stderr, "| mark: %u markers referenced, %u weak references freed,\n" "| %d things to free, " "got %"PRINTSIZET"u tricky weak refs\n", marked, weak_freed, delayed_freed, gc_ext_weak_refs)); } { #ifdef PIKE_DEBUG size_t orig_ext_weak_refs = gc_ext_weak_refs; obj_count = delayed_freed; #endif Pike_in_gc=GC_PASS_CYCLE; /* Now find all cycles in the internal structures. Note that we can * follow the same reference several times, just like in the mark * pass. */ /* Note: The order between types here is normally not significant, * but the permuting destruct order tests in the testsuite won't be * really effective unless objects are handled first. :P */ gc_cycle_check_all_objects(); gc_cycle_check_all_arrays(); gc_cycle_check_all_multisets(); gc_cycle_check_all_mappings(); gc_cycle_check_all_programs(); #ifdef PIKE_DEBUG if (stack_top != &sentinel_frame) Pike_fatal("Frame stack not empty at end of cycle check pass.\n"); if (gc_ext_weak_refs != orig_ext_weak_refs) Pike_fatal("gc_ext_weak_refs changed from %"PRINTSIZET"u " "to %"PRINTSIZET"u in cycle check pass.\n", orig_ext_weak_refs, gc_ext_weak_refs); #endif GC_VERBOSE_DO(fprintf(stderr, "| cycle: %u internal things visited,\n" "| %u weak references freed, %d more things to free,\n" "| %u mark live visits, %u frame rotations,\n" "| %u links searched, used max %u link frames,\n" "| %u rec frames and %u free extra frames\n", cycle_checked, weak_freed, delayed_freed - obj_count, mark_live, frame_rot, link_search, max_link_frames, max_rec_frames, free_extra_frames)); #ifdef PIKE_DEBUG if (link_frames) fatal ("Leaked %u link frames.\n", link_frames); #endif } if (gc_ext_weak_refs) { size_t to_free = gc_ext_weak_refs; #ifdef PIKE_DEBUG obj_count = delayed_freed; #endif Pike_in_gc = GC_PASS_ZAP_WEAK; /* Zap weak references from external to internal things. That * occurs when something has both external weak refs and nonweak * cyclic refs from internal things. */ gc_zap_ext_weak_refs_in_mappings(); gc_zap_ext_weak_refs_in_arrays(); gc_zap_ext_weak_refs_in_multisets(); gc_zap_ext_weak_refs_in_objects(); gc_zap_ext_weak_refs_in_programs(); GC_VERBOSE_DO( fprintf(stderr, "| zap weak: freed %"PRINTPTRDIFFT"d external weak refs, " "%"PRINTSIZET"u internal still around,\n" "| %d more things to free\n", to_free - gc_ext_weak_refs, gc_ext_weak_refs, delayed_freed - obj_count)); } if (gc_debug) { unsigned n; #ifdef DEBUG_MALLOC size_t i; struct marker *m; #endif Pike_in_gc=GC_PASS_POSTTOUCH; n = gc_touch_all_arrays(); n += gc_touch_all_multisets(); n += gc_touch_all_mappings(); n += gc_touch_all_programs(); n += gc_touch_all_objects(); #ifdef PIKE_DEBUG gc_touch_all_strings(); #endif if (n != (unsigned) num_objects && !got_unlinked_things) Pike_fatal("Object count wrong in gc; expected %d, got %d.\n", num_objects, n); #if 0 /* Temporarily disabled - Hubbe */ #ifdef PIKE_DEBUG #ifdef DEBUG_MALLOC PTR_HASH_LOOP(marker, i, m) if (!(m->flags & (GC_POSTTOUCHED|GC_WEAK_FREED)) && dmalloc_is_invalid_memory_block(m->data)) { fprintf(stderr, "Found a stray marker after posttouch pass: "); describe_marker(m); fprintf(stderr, "Describing marker location(s):\n"); debug_malloc_dump_references(m, 2, 1, 0); fprintf(stderr, "Describing thing for marker:\n"); Pike_in_gc = 0; describe(m->data); Pike_in_gc = GC_PASS_POSTTOUCH; Pike_fatal("Fatal in garbage collector.\n"); } #endif #endif #endif GC_VERBOSE_DO(fprintf(stderr, "| posttouch\n")); } /* Object alloc/free and reference changes are allowed again now. */ Pike_in_gc=GC_PASS_FREE; #ifdef PIKE_DEBUG weak_freed = 0; obj_count = num_objects; #endif /* Now we free the unused stuff. The extra refs to gc_internal_* * added above are removed just before the calls so we'll get the * correct relative positions in them. */ unreferenced = 0; if (gc_internal_array) unreferenced += gc_free_all_unreferenced_arrays(); if (gc_internal_multiset) unreferenced += gc_free_all_unreferenced_multisets(); if (gc_internal_mapping) unreferenced += gc_free_all_unreferenced_mappings(); if (gc_internal_object) unreferenced += gc_free_all_unreferenced_objects(); /* Note: gc_free_all_unreferenced_objects needs to have the programs * around to handle the free (even when they aren't live). So it's * necessary to free the objects before the programs. */ if (gc_internal_program) unreferenced += gc_free_all_unreferenced_programs(); if (free_extra_frames > tot_max_free_extra_frames) tot_max_free_extra_frames = free_extra_frames; /* We might occasionally get things to gc_delayed_free that the free * calls above won't find. They're tracked in this list. */ while (free_extra_list) { struct free_extra_frame *next = free_extra_list->next; union anything u; u.refs = (INT32 *) free_extra_list->data; gc_free_extra_ref (u.refs); free_short_svalue (&u, free_extra_list->type); really_free_free_extra_frame (free_extra_list); free_extra_list = next; } #ifdef PIKE_DEBUG if (free_extra_frames) fatal ("Leaked %u free extra frames.\n", free_extra_frames); #endif GC_VERBOSE_DO(fprintf(stderr, "| free: %"PRINTSIZET"u unreferenced, " "%d really freed, %u left with live references\n", unreferenced, obj_count - num_objects, live_ref)); #ifdef PIKE_DEBUG gc_internal_array = (struct array *) (ptrdiff_t) -1; gc_internal_multiset = (struct multiset *) (ptrdiff_t) -1; gc_internal_mapping = (struct mapping *) (ptrdiff_t) -1; gc_internal_program = (struct program *) (ptrdiff_t) -1; gc_internal_object = (struct object *) (ptrdiff_t) -1; if(fatal_after_gc) Pike_fatal("%s", fatal_after_gc); #endif Pike_in_gc=GC_PASS_KILL; /* Destruct the live objects in cycles, but first warn about any bad * cycles. */ pre_kill_objs = num_objects; if (Pike_interpreter.evaluator_stack && !gc_destruct_everything) { objs -= num_objects; warn_bad_cycles(); objs += num_objects; } #if defined (PIKE_DEBUG) || defined (DO_PIKE_CLEANUP) destroy_count = 0; #endif { enum object_destruct_reason reason = #ifdef DO_PIKE_CLEANUP gc_destruct_everything ? DESTRUCT_CLEANUP : #endif DESTRUCT_GC; #ifdef PIKE_DEBUG { struct gc_rec_frame *r; for (r = kill_list; r != &sentinel_frame; r = r->next) /* Can't do this while the list is being freed below. */ CHECK_KILL_LIST_FRAME (r); } #endif while (kill_list != &sentinel_frame) { struct gc_rec_frame *next = kill_list->next; struct object *o = (struct object *) kill_list->data; #ifdef PIKE_DEBUG if ((get_marker(kill_list->data)->flags & (GC_LIVE|GC_LIVE_OBJ)) != (GC_LIVE|GC_LIVE_OBJ)) gc_fatal(o, 0, "Invalid object on kill list.\n"); if (o->prog && (o->prog->flags & PROGRAM_USES_PARENT) && PARENT_INFO(o)->parent && !PARENT_INFO(o)->parent->prog && get_marker(PARENT_INFO(o)->parent)->flags & GC_LIVE_OBJ) gc_fatal(o, 0, "GC destructed parent prematurely.\n"); #endif GC_VERBOSE_DO( fprintf(stderr, "| Killing %p with %d refs", o, o->refs); if (o->prog) { INT32 line; struct pike_string *file = get_program_line (o->prog, &line); fprintf(stderr, ", prog %s:%d\n", file->str, line); free_string(file); } else fputs(", is destructed\n", stderr); ); destruct_object (o, reason); free_object(o); gc_free_extra_ref(o); #if defined (PIKE_DEBUG) || defined (DO_PIKE_CLEANUP) destroy_count++; #endif really_free_gc_rec_frame (kill_list); kill_list = next; } } #ifdef PIKE_DEBUG if (rec_frames) fatal ("Leaked %u rec frames.\n", rec_frames); #endif GC_VERBOSE_DO(fprintf(stderr, "| kill: %u objects killed, " "%"PRINTSIZET"u things really freed\n", destroy_count, pre_kill_objs - num_objects)); Pike_in_gc=GC_PASS_DESTRUCT; /* Destruct objects on the destruct queue. */ GC_VERBOSE_DO(obj_count = num_objects); destruct_objects_to_destruct(); GC_VERBOSE_DO(fprintf(stderr, "| destruct: %d things really freed\n", obj_count - num_objects)); #ifdef PIKE_DEBUG if (gc_extra_refs) { size_t e; fprintf (stderr, "Lost track of %d extra refs to things in gc.\n" "Searching for marker(s) with extra refs:\n", gc_extra_refs); for (e = 0; e < marker_hash_table_size; e++) { struct marker *s = marker_hash_table[e], *m; for (m = s; m;) { if (m->flags & GC_GOT_EXTRA_REF) { fprintf (stderr, "========================================\n" "Found marker with extra ref: "); describe_marker (m); fprintf (stderr, "Describing the thing pointed to:\n"); describe (m->data); } m = m->next; /* The marker might be moved to the head of the chain via * describe() above, so do this to avoid infinite recursion. * Some entries in the chain might be missed, but I don't want * to bother. */ if (m == s) break; } } fprintf (stderr, "========================================\n" "Done searching for marker(s) with extra refs.\n"); Pike_fatal("Lost track of %d extra refs to things in gc.\n", gc_extra_refs); } if(fatal_after_gc) Pike_fatal("%s", fatal_after_gc); #endif /* Calculate the next alloc_threshold. */ { double multiplier, new_threshold; cpu_time_t last_non_gc_time, last_gc_time; /* If we're at an automatic and timely gc then start_allocs == * alloc_threshold and we're using gc_average_slowness in the * decaying average calculation. Otherwise this is either an * explicit call (start_allocs < alloc_threshold) or the gc has * been delayed past its due time (start_allocs > * alloc_threshold), and in those cases we adjust the multiplier * to give the appropriate weight to this last instance. */ multiplier=pow(gc_average_slowness, (double) start_allocs / (double) alloc_threshold); /* Comparisons to avoid that overflows mess up the statistics. */ if (gc_start_time > last_gc_end_time) { last_non_gc_time = gc_start_time - last_gc_end_time; non_gc_time = non_gc_time * multiplier + last_non_gc_time * (1.0 - multiplier); } else last_non_gc_time = (cpu_time_t) -1; last_gc_end_time = get_cpu_time(); if (last_gc_end_time > gc_start_time) { last_gc_time = last_gc_end_time - gc_start_time; gc_time = gc_time * multiplier + last_gc_time * (1.0 - multiplier); } else last_gc_time = (cpu_time_t) -1; /* At this point, unreferenced contains the number of things that * were without external references during the check and mark * passes. In the process of freeing them, destroy functions might * have been called which means anything might have happened. * Therefore we use that figure instead of the difference between * the number of allocated things to measure the amount of * garbage. */ last_garbage_ratio = (double) unreferenced / start_num_objs; objects_alloced = objects_alloced * multiplier + start_allocs * (1.0 - multiplier); objects_freed = objects_freed * multiplier + unreferenced * (1.0 - multiplier); if (last_non_gc_time == (cpu_time_t) -1 || gc_time / non_gc_time <= gc_time_ratio) { /* Calculate the new threshold by adjusting the average * threshold (objects_alloced) with the ratio between the wanted * garbage at the next gc (gc_garbage_ratio_low * * start_num_objs) and the actual average garbage * (objects_freed). (Where the +1.0's come from I don't know. * Perhaps they're to avoid division by zero. /mast) */ new_threshold = (objects_alloced+1.0) * (gc_garbage_ratio_low * start_num_objs) / (objects_freed+1.0); last_garbage_strategy = GARBAGE_RATIO_LOW; } else { new_threshold = (objects_alloced+1.0) * (gc_garbage_ratio_high * start_num_objs) / (objects_freed+1.0); last_garbage_strategy = GARBAGE_RATIO_HIGH; } #if 0 /* Afaics this is to limit the growth of the threshold to avoid * that a single sudden allocation spike causes a very long gc * interval the next time. Now when the bug in the decaying * average calculation is fixed there should be no risk for that, * at least not in any case when this would help. /mast */ if(alloc_threshold + start_allocs < new_threshold) new_threshold = (double)(alloc_threshold + start_allocs); #endif if(new_threshold < GC_MIN_ALLOC_THRESHOLD) alloc_threshold = GC_MIN_ALLOC_THRESHOLD; else if(new_threshold > GC_MAX_ALLOC_THRESHOLD) alloc_threshold = GC_MAX_ALLOC_THRESHOLD; else alloc_threshold = (ALLOC_COUNT_TYPE) new_threshold; if (!explicit_call && last_gc_time != (cpu_time_t) -1) { #ifdef CPU_TIME_MIGHT_BE_THREAD_LOCAL if (cpu_time_is_thread_local #ifdef PIKE_DEBUG /* At high debug levels, the gc may get called before * the threads are initialized. */ && Pike_interpreter.thread_state #endif ) Pike_interpreter.thread_state->auto_gc_time += last_gc_time; else #endif { #ifdef CPU_TIME_MIGHT_NOT_BE_THREAD_LOCAL auto_gc_time += last_gc_time; #endif } } if(GC_VERBOSE_DO(1 ||) gc_trace) { char timestr[40]; if (last_gc_time != (cpu_time_t) -1) sprintf (timestr, ", %ld ms", (long) (last_gc_time / (CPU_TIME_TICKS / 1000))); else timestr[0] = 0; #ifdef DO_PIKE_CLEANUP if (gc_destruct_everything) fprintf(stderr, "done (%u %s destructed)%s\n", destroy_count, destroy_count == 1 ? "was" : "were", timestr); else #endif fprintf(stderr, "done (%"PRINTSIZET"u of %"PRINTSIZET"u " "%s unreferenced)%s\n", unreferenced, start_num_objs, unreferenced == 1 ? "was" : "were", timestr); } } #ifdef PIKE_DEBUG UNSET_ONERROR (uwp); tot_cycle_checked += cycle_checked; tot_mark_live += mark_live, tot_frame_rot += frame_rot; #endif if (max_rec_frames > tot_max_rec_frames) tot_max_rec_frames = max_rec_frames; if (max_link_frames > tot_max_link_frames) tot_max_link_frames = max_link_frames; Pike_in_gc=0; exit_gc(); #ifdef ALWAYS_GC ADD_GC_CALLBACK(); #else if(d_flag > 3) ADD_GC_CALLBACK(); #endif #ifdef DO_PIKE_CLEANUP if (gc_destruct_everything) return destroy_count; #endif return unreferenced; } /*! @decl mapping(string:int|float) gc_status() *! @belongs Debug *! *! Get statistics from the garbage collector. *! *! @returns *! A mapping with the following content will be returned: *! @mapping *! @member int "num_objects" *! Number of arrays, mappings, multisets, objects and programs. *! @member int "num_allocs" *! Number of memory allocations since the last gc run. *! @member int "alloc_threshold" *! Threshold for "num_allocs" when another automatic gc run is *! scheduled. *! @member float "projected_garbage" *! Estimation of the current amount of garbage. *! @member int "objects_alloced" *! Decaying average over the number of allocated objects *! between gc runs. *! @member int "objects_freed" *! Decaying average over the number of freed objects in each gc *! run. *! @member float "last_garbage_ratio" *! Garbage ratio in the last gc run. *! @member int "non_gc_time" *! Decaying average over the CPU milliseconds spent outside the *! garbage collector. *! @member int "gc_time" *! Decaying average over the CPU milliseconds spent inside the *! garbage collector. *! @member string "last_garbage_strategy" *! The garbage accumulation goal that the gc aimed for when *! setting "alloc_threshold" in the last run. The value is *! either "garbage_ratio_low" or "garbage_ratio_high", which *! corresponds to the gc parameters with the same names in *! @[Pike.gc_parameters]. *! @member int "last_gc" *! Time when the garbage-collector last ran. *! @endmapping *! *! @seealso *! @[gc()], @[Pike.gc_parameters()] */ void f__gc_status(INT32 args) { int size = 0; pop_n_elems(args); push_constant_text("num_objects"); push_int(num_objects); size++; push_constant_text("num_allocs"); push_int64(num_allocs); size++; push_constant_text("alloc_threshold"); push_int64(alloc_threshold); size++; push_constant_text("projected_garbage"); push_float(DO_NOT_WARN((FLOAT_TYPE)(objects_freed * (double) num_allocs / (double) alloc_threshold))); size++; push_constant_text("objects_alloced"); push_int64(DO_NOT_WARN((INT64)objects_alloced)); size++; push_constant_text("objects_freed"); push_int64(DO_NOT_WARN((INT64)objects_freed)); size++; push_constant_text("last_garbage_ratio"); push_float(DO_NOT_WARN((FLOAT_TYPE) last_garbage_ratio)); size++; push_constant_text("non_gc_time"); push_int64(DO_NOT_WARN((INT64) non_gc_time)); size++; push_constant_text("gc_time"); push_int64(DO_NOT_WARN((INT64) gc_time)); size++; push_constant_text ("last_garbage_strategy"); switch (last_garbage_strategy) { case GARBAGE_RATIO_LOW: push_constant_text ("garbage_ratio_low"); break; case GARBAGE_RATIO_HIGH: push_constant_text ("garbage_ratio_high"); break; #ifdef PIKE_DEBUG default: Pike_fatal ("Unknown last_garbage_strategy %d\n", last_garbage_strategy); #endif } size++; push_constant_text("last_gc"); push_int64(last_gc); size++; #ifdef PIKE_DEBUG push_constant_text ("max_rec_frames"); push_int64 (DO_NOT_WARN ((INT64) tot_max_rec_frames)); size++; push_constant_text ("max_link_frames"); push_int64 (DO_NOT_WARN ((INT64) tot_max_link_frames)); size++; push_constant_text ("max_free_extra_frames"); push_int64 (DO_NOT_WARN ((INT64) tot_max_free_extra_frames)); size++; #endif f_aggregate_mapping(size * 2); } void dump_gc_info(void) { fprintf(stderr,"Current number of things : %d\n",num_objects); fprintf(stderr,"Allocations since last gc : "PRINT_ALLOC_COUNT_TYPE"\n", num_allocs); fprintf(stderr,"Threshold for next gc : "PRINT_ALLOC_COUNT_TYPE"\n", alloc_threshold); fprintf(stderr,"Projected current garbage : %f\n", objects_freed * (double) num_allocs / (double) alloc_threshold); fprintf(stderr,"Avg allocs between gc : %f\n",objects_alloced); fprintf(stderr,"Avg frees per gc : %f\n",objects_freed); fprintf(stderr,"Garbage ratio in last gc : %f\n", last_garbage_ratio); fprintf(stderr,"Avg cpu "CPU_TIME_UNIT" between gc : %f\n", non_gc_time); fprintf(stderr,"Avg cpu "CPU_TIME_UNIT" in gc : %f\n", gc_time); fprintf(stderr,"Avg time ratio in gc : %f\n", gc_time / non_gc_time); fprintf(stderr,"Garbage strategy in last gc: %s\n", last_garbage_strategy == GARBAGE_RATIO_LOW ? "garbage_ratio_low" : last_garbage_strategy == GARBAGE_RATIO_HIGH ? "garbage_ratio_high" : "???"); #ifdef PIKE_DEBUG fprintf(stderr,"Max used recursion frames : %u\n", tot_max_rec_frames); fprintf(stderr,"Max used link frames : %u\n", tot_max_link_frames); fprintf(stderr,"Max used free extra frames : %u\n", tot_max_free_extra_frames); fprintf(stderr,"Marked live ratio : %g\n", (double) tot_mark_live / tot_cycle_checked); fprintf(stderr,"Frame rotation ratio : %g\n", (double) tot_frame_rot / tot_cycle_checked); #endif fprintf(stderr,"in_gc : %d\n", Pike_in_gc); } void cleanup_gc(void) { #ifdef PIKE_DEBUG if (gc_evaluator_callback) { remove_callback(gc_evaluator_callback); gc_evaluator_callback = NULL; } #endif /* PIKE_DEBUG */ } /* Visit things API */ PMOD_EXPORT visit_ref_cb *visit_ref = NULL; /* Be careful if extending this with internal types like * T_MAPPING_DATA and T_MULTISET_DATA; there's code that assumes * type_from_visit_fn only returns types that fit in a TYPE_FIELD. */ PMOD_EXPORT visit_thing_fn *const visit_fn_from_type[MAX_REF_TYPE + 1] = { (visit_thing_fn *) &visit_array, (visit_thing_fn *) &visit_mapping, (visit_thing_fn *) &visit_multiset, (visit_thing_fn *) &visit_object, /* visit_function must be called with a whole svalue, so it's not * included here. */ (visit_thing_fn *) (ptrdiff_t) -1, (visit_thing_fn *) &visit_program, (visit_thing_fn *) &visit_string, (visit_thing_fn *) &visit_type, }; PMOD_EXPORT TYPE_T type_from_visit_fn (visit_thing_fn *fn) { /* Since the array to search is so small, linear search is probably * fastest. */ unsigned t; for (t = 0; t < NELEM (visit_fn_from_type); t++) if (visit_fn_from_type[t] == fn) return (TYPE_T) t; return PIKE_T_UNKNOWN; } /* Memory counting * * This mode is used by f_count_memory, and it's recognized by a * nonzero value in mc_pass. * * The basic idea is to follow and count all refs from the starting * point things given to f_count_memory. Whenever the counted refs add * up to the refcount for a thing, that thing is known to have only * internal refs, and so it's memory counted and then all its refs are * followed too. * * To cope with internal cyclic refs, there's a "lookahead" algorithm * which recurses through more things in the hope of finding cycles * that otherwise would make us miss internal refs. This lookahead is * limited by mc_lookahead, mc_block_lookahead, and the constant or * variable "pike_cycle_depth" in objects. * * All things are categorized as follows: * * o Internal things: These are known to have only internal * references and are memory counted. The things given to * f_count_memory as starting points are initially asserted to be * internal regardless of how many refs they got. * * o Lookahead things: A lookahead thing is one that has been found * by following refs from an internal thing. * * Lookahead things are further divided into three categories: * * o Incomplete: Things whose refcounts (still) are higher than * all found refs to them from both internal and lookahead * things. * * o Complete: Things whose refs from internal and lookahead * things equal their refcounts. I.e. we've found all refs going * to these. * * Complete things can also be "candidates", which means they * have a direct ref from an internal thing or another * candidate. * * o Indirectly incomplete: In MC_PASS_MARK_EXTERNAL, these are * all the complete things found to be referenced by incomplete * things. * * These sets are tracked through three double linked lists, * mc_incomplete, mc_complete, and mc_indirect, respectively. * * The lookahead is controlled by a lookahead count for each thing. * The count is the number of links to follow emanating from that * thing. The count for internal things and candidates default to * mc_lookahead, but if a thing is an object with a * "pike_cycle_depth" variable, that number overrides it. * * As links are followed to other things, their lookahead count * gets lowered, and the lookahead stops when it reaches zero (or * when reaching a thing of a type in mc_block_lookahead). If a * lookahead thing is found later on through another path with * fewer links, its lookahead count is raised so that it eventually * reflects the shortest path. * * The reason for the "candidate" things which are kept at max * lookahead count is that the lookahead thereby continue as long * as it resolves complete things which eventually might turn out * to be internal. That means the lookahead distance only needs to * be large enough to cover the largest "loop" inside a structure * with many cycles, rather than the longest cyclic path. * * E.g. to cover a double linked list which can be arbitrary long, * it's enough that mc_lookahead is 3; that makes the lookahead * account for the two refs to the next node (B) from the previous * complete node (A), by traversing through the next-to-next node * (C): * 3 * L---. L---. L---. L---. * ... (A) (B) (C) ... * `---7 `---7 `---7 `---7 * 1 2 * * o Unvisited things: Everything else that hasn't been visited yet. * * For every visited thing we record the number of refs from internal * things (int_refs) and from lookahead things (la_refs). * * The basic algorithm for finding all internal things works like * this: * * First the starting point things are labelled internal and put into * the work queue (mc_work_queue). * * mc_pass is set to MC_PASS_LOOKAHEAD: * * We do a breadth-first recursion through the things in the work * queue until the lookahead count reaches zero, always starting with * the things with the highest count. * * Every time we visit something we calculate its lookahead count as * either max (if it's found to be referenced from an internal or * candidate thing), the same as the source thing (if the followed ref * is REF_TYPE_INTERNAL), or the next lower count (otherwise). If the * count is above zero and the thing is either new or its old count * was lower, it's added to the work list. * * mc_work_queue is a priority queue which always has the thing with * the highest lookahead count first, thereby ensuring breadth-first * recursion also when things have their count raised. * * int_refs and la_refs are updated when things are visited. They * become internal if int_refs add up to the refcount. Otherwise they * are put in the incomplete or complete sets as appropriate. * * mc_pass is set to MC_PASS_MARK_EXTERNAL: * * At this point the set of lookahead things is complete (as far as we * are concerned), and it's divided into complete and incomplete * lookahead things. All references in the incomplete list are * followed to build up the set of indirectly incomplete things. The * incomplete and indirectly incomplete things are referenced * externally and should not be memory counted. * * If there's anything left in the complete list then it's internal * cyclic stuff. In that case we put those things into the work list, * move the indirectly incomplete list back to complete and repeat * MC_PASS_LOOKAHEAD. Otherwise we're done. */ /* #define MEMORY_COUNT_DEBUG */ #define MC_WQ_START_SIZE 1024 PMOD_EXPORT int mc_pass; PMOD_EXPORT size_t mc_counted_bytes; static int mc_lookahead, mc_block_pike_cycle_depth; static TYPE_FIELD mc_block_lookahead; static TYPE_FIELD mc_block_lookahead_default = BIT_PROGRAM|BIT_STRING|BIT_TYPE; /* Strings are blocked because they don't contain refs. Types are * blocked because they are acyclic and don't contain refs to anything * but strings and other types. */ static int mc_enqueued_noninternal; /* Set whenever something is enqueued in MC_PASS_LOOKAHEAD that isn't * internal already. This is used to detect whether another * MC_PASS_MARK_EXTERNAL is necessary. */ static unsigned mc_ext_toggle_bias = 0; #define MC_PASS_LOOKAHEAD 1 #define MC_PASS_MARK_EXTERNAL 2 /* Set when a thing has become internal. */ #define MC_FLAG_INTERNAL 0x01 /* Set when an internal thing has been visited, i.e. after its refs * has been gone through for the first time. This implies that the * thing has been memory counted, and taken off mc_incomplete or * mc_complete if it was there. */ #define MC_FLAG_INT_VISITED 0x02 /* Set when a non-internal thing has been visited. If * MC_FLAG_INT_VISITED isn't then the thing is on one of mc_incomplete, * mc_complete, or (in MC_PASS_MARK_EXTERNAL) mc_indirect. */ #define MC_FLAG_LA_VISITED 0x04 /* Set when a thing has become a candidate (i.e. complete and * referenced directly from an internal or candidate thing). This * flag is meaningless when MC_FLAG_INTERNAL is set. */ #define MC_FLAG_CANDIDATE 0x08 /* Set when a thing is visited directly from an internal or candidate * thing. */ #define MC_FLAG_CANDIDATE_REF 0x10 /* The lookahead count should not change. Use when it has been lowered * from pike_cycle_depth. */ #define MC_FLAG_LA_COUNT_FIXED 0x20 /* A toggle flag to mark external (i.e. incomplete and indirectly * incomplete) things in MC_PASS_MARK_EXTERNAL so that we don't * recurse them repeatedly. If mc_ext_toggle_bias is zero then it's * external if this is set. If mc_ext_toggle_bias is one then it's * external if this is cleared. mc_ext_toggle_bias toggles every time * we leave MC_PASS_MARK_EXTERNAL, thus we avoid the work to go * through the externals clear the flag for the next round. */ #define MC_FLAG_EXT_TOGGLE 0x40 /* The value of IS_EXTERNAL is meaningless when MC_FLAG_INTERNAL is set. */ #define IS_EXTERNAL(M) \ (((M)->flags ^ mc_ext_toggle_bias) & MC_FLAG_EXT_TOGGLE) #define INIT_CLEARED_EXTERNAL(M) do { \ struct mc_marker *_m = (M); \ if (mc_ext_toggle_bias) _m->flags |= MC_FLAG_EXT_TOGGLE; \ } while (0) #define FLAG_EXTERNAL(M) do { \ struct mc_marker *_m = (M); \ assert (!IS_EXTERNAL (_m)); \ _m->flags ^= MC_FLAG_EXT_TOGGLE; \ } while (0) #define TOGGLE_EXT_FLAGS() do { \ mc_ext_toggle_bias ^= MC_FLAG_EXT_TOGGLE; \ } while (0) struct mc_marker { struct mc_marker *hash_next; /* Used by PTR_HASH_ALLOC. */ struct mc_marker *dl_prev; /* For the mc_incomplete, mc_complete and */ struct mc_marker *dl_next; /* mc_indirect lists. Used iff not internal.*/ void *thing; /* Referenced thing. */ visit_thing_fn *visit_fn; /* Visit function for it */ void *extra; /* and its extra data. */ INT32 int_refs; /* These refcounts are bogus */ INT32 la_refs; /* for internal things. */ unsigned INT32 queuepos; /* Position in mc_work_queue, or * MAX_UINT32 if not queued. */ unsigned INT16 la_count; /* Lookahead count. */ unsigned INT16 flags; }; #undef BLOCK_ALLOC_NEXT #undef BLOCK_ALLOC_NEXT #define BLOCK_ALLOC_NEXT hash_next #undef PTR_HASH_ALLOC_DATA #define PTR_HASH_ALLOC_DATA thing #undef INIT_BLOCK #define INIT_BLOCK(f) #undef EXIT_BLOCK #define EXIT_BLOCK(f) PTR_HASH_ALLOC_FILL_PAGES (mc_marker, 2) static struct mc_marker *my_make_mc_marker (void *thing, visit_thing_fn *visit_fn, void *extra) { struct mc_marker *m = make_mc_marker (thing); assert (thing); assert (visit_fn); m->thing = thing; m->visit_fn = visit_fn; m->extra = extra; m->int_refs = m->la_refs = m->flags = 0; INIT_CLEARED_EXTERNAL (m); m->queuepos = MAX_UINT32; #ifdef PIKE_DEBUG m->dl_prev = m->dl_next = (void *) (ptrdiff_t) -1; m->la_count = ((unsigned INT16) -1) >> 1; #endif return m; } #if defined (PIKE_DEBUG) || defined (MEMORY_COUNT_DEBUG) static void describe_mc_marker (struct mc_marker *m) { fprintf (stderr, "%s %p: refs %d, int %d, la %d, cnt %d", get_name_of_type (type_from_visit_fn (m->visit_fn)), m->thing, *(INT32 *) m->thing, m->int_refs, m->la_refs, m->la_count); if (m->queuepos != MAX_UINT32) fprintf (stderr, ", wq %u", m->queuepos); if (m->flags & MC_FLAG_INTERNAL) fputs (", I", stderr); if (m->flags & MC_FLAG_INT_VISITED) fputs (", IV", stderr); if (m->flags & MC_FLAG_LA_VISITED) fputs (", LAV", stderr); if (m->flags & MC_FLAG_CANDIDATE) fputs (", C", stderr); if (m->flags & MC_FLAG_CANDIDATE_REF) fputs (", CR", stderr); if (m->flags & MC_FLAG_LA_COUNT_FIXED) fputs (", CF", stderr); if (IS_EXTERNAL (m)) fputs (m->flags & MC_FLAG_INTERNAL ? ", (E)" : ", E", stderr); } #endif /* Sentinel for the incomplete lookaheads list. */ static struct mc_marker mc_incomplete = { (void *) (ptrdiff_t) -1, &mc_incomplete, &mc_incomplete, (void *) (ptrdiff_t) -1, (visit_thing_fn *) (ptrdiff_t) -1, (void *) (ptrdiff_t) -1, -1, -1, MAX_UINT32, 0, (unsigned INT16) -1 }; /* Sentinel for the complete lookaheads list. The reason all complete * things are tracked and not only the candidates is that elements * then can be easily moved to mc_indirect (and back) without special * cases when noncandidate complete things become indirectly * incomplete. */ static struct mc_marker mc_complete = { (void *) (ptrdiff_t) -1, &mc_complete, &mc_complete, (void *) (ptrdiff_t) -1, (visit_thing_fn *) (ptrdiff_t) -1, (void *) (ptrdiff_t) -1, -1, -1, MAX_UINT32, 0, (unsigned INT16) -1 }; /* Sentinel for the indirectly incomplete lookaheads list. */ static struct mc_marker mc_indirect = { (void *) (ptrdiff_t) -1, &mc_indirect, &mc_indirect, (void *) (ptrdiff_t) -1, (visit_thing_fn *) (ptrdiff_t) -1, (void *) (ptrdiff_t) -1, -1, -1, MAX_UINT32, 0, (unsigned INT16) -1 }; #define DL_IS_EMPTY(LIST) (LIST.dl_next == &LIST) #define DL_ADD_LAST(LIST, M) do { \ struct mc_marker *_m = (M); \ struct mc_marker *_list_prev = LIST.dl_prev; \ DO_IF_DEBUG ( \ assert (_m->dl_prev == (void *) (ptrdiff_t) -1); \ assert (_m->dl_next == (void *) (ptrdiff_t) -1); \ ); \ _m->dl_prev = _list_prev; \ _m->dl_next = &LIST; \ LIST.dl_prev = _list_prev->dl_next = _m; \ } while (0) #define DL_REMOVE(M) do { \ struct mc_marker *_m = (M); \ struct mc_marker *_list_prev = _m->dl_prev; \ struct mc_marker *_list_next = _m->dl_next; \ assert (_m->dl_prev != (void *) (ptrdiff_t) -1); \ assert (_m->dl_next != (void *) (ptrdiff_t) -1); \ _list_prev->dl_next = _list_next; \ _list_next->dl_prev = _list_prev; \ DO_IF_DEBUG (_m->dl_prev = _m->dl_next = (void *) (ptrdiff_t) -1); \ } while (0) #define DL_MOVE(FROM_LIST, TO_LIST) do { \ if (FROM_LIST.dl_next != &FROM_LIST) { \ struct mc_marker *to_list_last = TO_LIST.dl_prev; \ TO_LIST.dl_prev = FROM_LIST.dl_prev; \ to_list_last->dl_next = FROM_LIST.dl_next; \ FROM_LIST.dl_prev->dl_next = &TO_LIST; \ FROM_LIST.dl_next->dl_prev = to_list_last; \ FROM_LIST.dl_prev = FROM_LIST.dl_next = &FROM_LIST; \ } \ } while (0) #define DL_MAKE_EMPTY(LIST) do { \ LIST.dl_prev = LIST.dl_next = &LIST; \ } while (0) static struct mc_marker *mc_ref_from = (void *) (ptrdiff_t) -1; #ifdef MEMORY_COUNT_DEBUG static void MC_DEBUG_MSG (struct mc_marker *m, const char *msg) { switch (mc_pass) { case MC_PASS_LOOKAHEAD: fputs ("LA ", stderr); break; case MC_PASS_MARK_EXTERNAL: fputs ("ME ", stderr); break; } if (m) { if (mc_ref_from != (void *) (ptrdiff_t) -1) fputs (" [", stderr); else fputs ("[", stderr); describe_mc_marker (m); fprintf (stderr, "] %s\n", msg); } else if (mc_ref_from != (void *) (ptrdiff_t) -1) { fputs ("{", stderr); describe_mc_marker (mc_ref_from); fprintf (stderr, "} %s\n", msg); } } #else #define MC_DEBUG_MSG(m, msg) do {} while (0) #endif /* The following is a standard binary heap priority queue implemented * using an array. C.f. http://www.sbhatnagar.com/SourceCode/pqueue.html. */ /* Note: 1-based indexing is used in mc_work_queue to avoid * off-by-ones in the binary arithmetic. */ static struct mc_marker **mc_work_queue = NULL; static unsigned INT32 mc_wq_size, mc_wq_used; #ifdef PIKE_DEBUG #define CHECK_WQ() if (d_flag) { \ unsigned i; \ assert (mc_wq_used >= 1); \ for (i = 1; i <= (mc_wq_used - 1) / 2; i++) { \ assert (mc_work_queue[i]->queuepos == i); \ assert (mc_work_queue[i]->la_count >= \ mc_work_queue[2 * i]->la_count); \ if (2 * i + 1 < mc_wq_used) \ assert (mc_work_queue[i]->la_count >= \ mc_work_queue[2 * i + 1]->la_count); \ } \ for (; i < mc_wq_used; i++) \ assert (mc_work_queue[i]->queuepos == i); \ } #else #define CHECK_WQ() do {} while (0) #endif static struct mc_marker *mc_wq_dequeue() { struct mc_marker *m; assert (mc_work_queue); if (mc_wq_used == 1) return NULL; m = mc_work_queue[1]; m->queuepos = MAX_UINT32; if (--mc_wq_used > 1) { struct mc_marker *n, *last = mc_work_queue[mc_wq_used]; int last_la_count = last->la_count; unsigned pos = 1; while (pos <= mc_wq_used / 2) { unsigned child_pos = 2 * pos; if (child_pos < mc_wq_used && mc_work_queue[child_pos]->la_count < mc_work_queue[child_pos + 1]->la_count) child_pos++; if (mc_work_queue[child_pos]->la_count <= last_la_count) break; n = mc_work_queue[pos] = mc_work_queue[child_pos]; n->queuepos = pos; pos = child_pos; } mc_work_queue[pos] = last; last->queuepos = pos; } CHECK_WQ(); return m; } static void mc_wq_enqueue (struct mc_marker *m) /* m may already be in the queue, provided that m->la_count isn't * lower than its old value. */ { struct mc_marker *n; unsigned pos; int m_la_count = m->la_count; assert (mc_work_queue); #ifdef PIKE_DEBUG assert (mc_lookahead < 0 || m_la_count != ((unsigned INT16) -1) >> 1); #endif if (m->queuepos != MAX_UINT32) { assert (m->queuepos < mc_wq_used); assert (m->queuepos * 2 >= mc_wq_used || m_la_count >= mc_work_queue[m->queuepos * 2]->la_count); assert (m->queuepos * 2 + 1 >= mc_wq_used || m_la_count >= mc_work_queue[m->queuepos * 2 + 1]->la_count); pos = m->queuepos; } else { if (mc_wq_used > mc_wq_size) { struct mc_marker **p; mc_wq_size *= 2; p = realloc (mc_work_queue + 1, mc_wq_size * sizeof (mc_work_queue[0])); if (!p) { make_error (msg_out_of_mem_2, mc_wq_size * sizeof (mc_work_queue[0])); free_svalue (&throw_value); move_svalue (&throw_value, --Pike_sp); mc_wq_size /= 2; return; } mc_work_queue = p - 1; /* Compensate for 1-based indexing. */ } pos = mc_wq_used++; } while (pos > 1 && (n = mc_work_queue[pos / 2])->la_count < m_la_count) { mc_work_queue[pos] = n; n->queuepos = pos; pos /= 2; } mc_work_queue[pos] = m; m->queuepos = pos; CHECK_WQ(); } static struct svalue pike_cycle_depth_str = SVALUE_INIT_FREE; static int mc_cycle_depth_from_obj (struct object *o) { struct program *p = o->prog; struct svalue val; if (!p) return 0; /* No need to look ahead in destructed objects. */ object_index_no_free2 (&val, o, 0, &pike_cycle_depth_str); if (val.type != T_INT) { int i = find_shared_string_identifier (pike_cycle_depth_str.u.string, p); INT32 line; struct pike_string *file = get_identifier_line (p, i, &line); make_error ("Object got non-integer pike_cycle_depth %O at %S:%d.\n", &val, file, line); free_svalue (&val); free_svalue (&throw_value); move_svalue (&throw_value, --Pike_sp); return -1; } if (val.subtype == NUMBER_UNDEFINED) return -1; if (val.u.integer > (unsigned INT16) -1) return (unsigned INT16) -1; if (val.u.integer < 0) { int i = find_shared_string_identifier (pike_cycle_depth_str.u.string, p); INT32 line; struct pike_string *file = get_identifier_line (p, i, &line); make_error ("Object got negative pike_cycle_depth at %S:%d.\n", &val, file, line); free_svalue (&throw_value); move_svalue (&throw_value, --Pike_sp); return -1; } return val.u.integer; } static void pass_lookahead_visit_ref (void *thing, int ref_type, visit_thing_fn *visit_fn, void *extra) { struct mc_marker *ref_to = find_mc_marker (thing); int ref_from_flags, ref_to_flags, old_la_count, ref_to_la_count; int ref_added = 0, check_new_candidate = 0, la_count_handled = 0; assert (mc_lookahead >= 0); assert (mc_pass == MC_PASS_LOOKAHEAD); #ifdef PIKE_DEBUG assert (mc_ref_from != (void *) (ptrdiff_t) -1); assert (mc_ref_from->la_count != ((unsigned INT16) -1) >> 1); #endif ref_from_flags = mc_ref_from->flags; /* Create mc_marker if necessary. */ if (!ref_to) { ref_to = my_make_mc_marker (thing, visit_fn, extra); MC_DEBUG_MSG (ref_to, "visiting new thing"); assert (!(ref_from_flags & (MC_FLAG_INT_VISITED | MC_FLAG_LA_VISITED))); ref_to_la_count = old_la_count = 0; } else if (ref_to->flags & MC_FLAG_INTERNAL) { /* Ignore refs to internal things. Can't treat them like other * things anyway since the int_refs aren't valid for the starting * points. */ MC_DEBUG_MSG (ref_to, "ignored internal"); assert (ref_to->la_count != ((unsigned INT16) -1) >> 1); return; } else { MC_DEBUG_MSG (ref_to, "visiting old thing"); ref_to_la_count = old_la_count = ref_to->la_count; assert (ref_to->la_count != ((unsigned INT16) -1) >> 1); } ref_to_flags = ref_to->flags; #define SET_LA_COUNT_FOR_INT_OR_CF() do { \ if (!(ref_to_flags & MC_FLAG_LA_COUNT_FIXED)) { \ int cycle_depth; \ if (visit_fn == (visit_thing_fn *) &visit_object && \ !mc_block_pike_cycle_depth && \ (cycle_depth = \ mc_cycle_depth_from_obj ((struct object *) thing)) >= 0) { \ ref_to_la_count = cycle_depth; \ ref_to_flags |= MC_FLAG_LA_COUNT_FIXED; \ MC_DEBUG_MSG (ref_to, "la_count set to pike_cycle_depth"); \ } \ \ else { \ int count_from_source = ref_type & REF_TYPE_INTERNAL ? \ mc_ref_from->la_count : mc_ref_from->la_count - 1; \ \ if (ref_to_la_count < mc_lookahead) { \ ref_to_la_count = mc_lookahead; \ MC_DEBUG_MSG (ref_to, "la_count raised to mc_lookahead"); \ } \ \ if (ref_to_la_count < count_from_source) { \ ref_to_la_count = count_from_source; \ MC_DEBUG_MSG (ref_to, count_from_source == mc_ref_from->la_count ? \ "la_count raised to source count" : \ "la_count raised to source count - 1"); \ } \ } \ } \ } while (0) if ((ref_from_flags & (MC_FLAG_INTERNAL | MC_FLAG_INT_VISITED)) == MC_FLAG_INTERNAL) { if (ref_from_flags & MC_FLAG_LA_VISITED) { /* mc_ref_from is a former lookahead thing that has become internal. */ assert (ref_to->la_refs > 0); ref_to->la_refs--; ref_to->int_refs++; MC_DEBUG_MSG (ref_to, "converted lookahead ref to internal"); } else { ref_to->int_refs++; MC_DEBUG_MSG (ref_to, "added internal ref"); ref_added = 1; } assert (ref_to->int_refs + ref_to->la_refs <= *(INT32 *) thing); /* Handle the target becoming internal. */ if (ref_to->int_refs == *(INT32 *) thing) { assert (!(ref_to_flags & MC_FLAG_INTERNAL)); assert (!(ref_to_flags & MC_FLAG_INT_VISITED)); ref_to_flags |= MC_FLAG_INTERNAL; SET_LA_COUNT_FOR_INT_OR_CF(); ref_to->flags = ref_to_flags; ref_to->la_count = ref_to_la_count; if (ref_to->queuepos != MAX_UINT32 && old_la_count == ref_to_la_count) MC_DEBUG_MSG (ref_to, "already in queue"); else { assert (ref_to->la_count >= old_la_count); mc_wq_enqueue (ref_to); MC_DEBUG_MSG (ref_to, "enqueued internal"); } return; } } if ((ref_from_flags & (MC_FLAG_INTERNAL | MC_FLAG_CANDIDATE)) && !(ref_to_flags & MC_FLAG_CANDIDATE_REF)) { ref_to_flags |= MC_FLAG_CANDIDATE_REF; MC_DEBUG_MSG (ref_to, "got candidate ref"); SET_LA_COUNT_FOR_INT_OR_CF(); check_new_candidate = la_count_handled = 1; } if (!(ref_from_flags & (MC_FLAG_INTERNAL | MC_FLAG_LA_VISITED))) { assert (ref_to->int_refs + ref_to->la_refs < *(INT32 *) thing); ref_to->la_refs++; MC_DEBUG_MSG (ref_to, "added lookahead ref"); ref_added = 1; } if (ref_added && (ref_to->int_refs + ref_to->la_refs == *(INT32 *) thing)) { MC_DEBUG_MSG (ref_to, "refs got complete"); check_new_candidate = 1; if (ref_to_flags & MC_FLAG_LA_VISITED) { /* Move to mc_complete if it has been lookahead visited. In other * cases this is handled after the lookahead visit is done. */ DL_REMOVE (ref_to); DL_ADD_LAST (mc_complete, ref_to); MC_DEBUG_MSG (ref_to, "moved to complete list"); } } /* Handle the target becoming a candidate. */ if (check_new_candidate && (ref_to_flags & MC_FLAG_CANDIDATE_REF) && ref_to->int_refs + ref_to->la_refs == *(INT32 *) thing) { assert (!(ref_to_flags & MC_FLAG_CANDIDATE)); assert (ref_to->la_refs > 0); ref_to_flags |= MC_FLAG_CANDIDATE; MC_DEBUG_MSG (ref_to, "made candidate"); ref_to->flags = ref_to_flags; ref_to->la_count = ref_to_la_count; if (mc_block_lookahead & (1 << type_from_visit_fn (visit_fn))) { MC_DEBUG_MSG (ref_to, "type is blocked - not enqueued"); return; } if (ref_to_la_count > 0) { /* Always enqueue if the count allows it, even if it hasn't * increased. That since MC_FLAG_CANDIDATE_REF must be propagated. */ if (ref_to->queuepos != MAX_UINT32 && old_la_count == ref_to_la_count) MC_DEBUG_MSG (ref_to, "already in queue"); else { assert (ref_to->la_count >= old_la_count); mc_wq_enqueue (ref_to); MC_DEBUG_MSG (ref_to, "enqueued candidate"); mc_enqueued_noninternal = 1; } } else MC_DEBUG_MSG (ref_to, "candidate not enqueued due to zero count"); return; } /* Normal handling. */ if (mc_block_lookahead & (1 << type_from_visit_fn (visit_fn))) { ref_to->flags = ref_to_flags; ref_to->la_count = ref_to_la_count; MC_DEBUG_MSG (ref_to, "type is blocked - not enqueued"); return; } if (!la_count_handled && !(ref_to_flags & MC_FLAG_LA_COUNT_FIXED)) { int cycle_depth; int count_from_source = ref_type & REF_TYPE_INTERNAL ? mc_ref_from->la_count : mc_ref_from->la_count - 1; if (ref_to_la_count < count_from_source) { ref_to_la_count = count_from_source; MC_DEBUG_MSG (ref_to, count_from_source == mc_ref_from->la_count ? "la_count raised to source count" : "la_count raised to source count - 1"); } if (visit_fn == (visit_thing_fn *) &visit_object && !mc_block_pike_cycle_depth && (cycle_depth = mc_cycle_depth_from_obj ((struct object *) thing)) >= 0 && cycle_depth < ref_to_la_count) { /* pike_cycle_depth is only allowed to lower the lookahead count * for things that aren't internal, candidates, or candidate ref'd. */ ref_to_la_count = cycle_depth; ref_to_flags |= MC_FLAG_LA_COUNT_FIXED; MC_DEBUG_MSG (ref_to, "la_count lowered to pike_cycle_depth"); } } ref_to->flags = ref_to_flags; ref_to->la_count = ref_to_la_count; assert (ref_to->la_count >= old_la_count); if (ref_to->la_count > old_la_count) { mc_wq_enqueue (ref_to); MC_DEBUG_MSG (ref_to, "enqueued"); mc_enqueued_noninternal = 1; } else MC_DEBUG_MSG (ref_to, "not enqueued"); } static void pass_mark_external_visit_ref (void *thing, int ref_type, visit_thing_fn *visit_fn, void *extra) { struct mc_marker *ref_to = find_mc_marker (thing); assert (mc_pass == MC_PASS_MARK_EXTERNAL); if (ref_to) { if ((ref_to->flags & (MC_FLAG_INT_VISITED | MC_FLAG_LA_VISITED)) == MC_FLAG_LA_VISITED) { /* Only interested in existing lookahead things, except those on * the "fringe" that haven't been visited. */ if (IS_EXTERNAL (ref_to)) MC_DEBUG_MSG (ref_to, "already external"); else { FLAG_EXTERNAL (ref_to); DL_REMOVE (ref_to); DL_ADD_LAST (mc_indirect, ref_to); MC_DEBUG_MSG (ref_to, "marked external - moved to indirect list"); assert (ref_to->int_refs + ref_to->la_refs == *(INT32 *) thing); } } else MC_DEBUG_MSG (ref_to, ref_to->flags & MC_FLAG_INTERNAL ? "ignored internal" : "ignored fringe thing"); } } static void current_only_visit_ref (void *thing, int ref_type, visit_thing_fn *visit_fn, void *extra) /* This is used when count_memory has a negative lookahead. It only * recurses through REF_TYPE_INTERNAL references. Note that most * fields in mc_marker aren't used. */ { struct mc_marker *ref_to = find_mc_marker (thing); int ref_from_flags; assert (mc_lookahead < 0); #ifdef PIKE_DEBUG assert (mc_ref_from != (void *) (ptrdiff_t) -1); #endif ref_from_flags = mc_ref_from->flags; assert (ref_from_flags & MC_FLAG_INTERNAL); assert (!(ref_from_flags & MC_FLAG_INT_VISITED)); if (!ref_to) { ref_to = my_make_mc_marker (thing, visit_fn, extra); MC_DEBUG_MSG (ref_to, "got new thing"); } else if (ref_to->flags & MC_FLAG_INTERNAL) { /* Ignore refs to the starting points. Can't treat them like other * things anyway since the int_refs aren't valid. */ MC_DEBUG_MSG (ref_to, "ignored starting point"); return; } else MC_DEBUG_MSG (ref_to, "got old thing"); if (!(ref_type & REF_TYPE_INTERNAL)) { MC_DEBUG_MSG (ref_to, "ignored non-internal ref"); return; } ref_to->int_refs++; MC_DEBUG_MSG (ref_to, "added really internal ref"); assert (ref_to->int_refs <= *(INT32 *) thing); if (ref_to->int_refs == *(INT32 *) thing) { ref_to->flags |= MC_FLAG_INTERNAL; mc_wq_enqueue (ref_to); MC_DEBUG_MSG (ref_to, "enqueued internal"); } } PMOD_EXPORT int mc_count_bytes (void *thing) { if (mc_pass == MC_PASS_LOOKAHEAD) { struct mc_marker *m = find_mc_marker (thing); #ifdef PIKE_DEBUG if (!m) Pike_fatal ("mc_marker not found for %p.\n", thing); #endif if ((m->flags & (MC_FLAG_INTERNAL|MC_FLAG_INT_VISITED)) == MC_FLAG_INTERNAL) return 1; } return 0; } /*! @decl int count_memory (int|mapping(string:int) options, @ *! array|multiset|mapping|object|program|string|type|int... things) *! @appears Pike.count_memory *! *! In brief, if you call @expr{Pike.count_memory(0,x)@} you get back *! the number of bytes @expr{x@} occupies in memory. *! *! The detailed story is a bit longer: *! *! This function calculates the number of bytes that all @[things] *! occupy. Or put another way, it calculates the number of bytes that *! would be freed if all those things would lose their references at *! the same time, i.e. not only the memory in the things themselves, *! but also in all the things that are directly and indirectly *! referenced from those things and not from anywhere else. *! *! The memory counted is only that which is directly occupied by the *! things in question, including any overallocation for mappings, *! multisets and arrays. Other memory overhead that they give rise to *! is not counted. This means that if you would count the memory *! occupied by all the pike accessible things you would get a figure *! significantly lower than what the OS gives for the pike process. *! *! Also, if you were to actually free the things, you should not *! expect the size of the pike process to drop the amount of bytes *! returned by this function. That since Pike often retains the *! memory to be reused later. *! *! However, what you should expect is that if you actually free the *! things and then later allocates some more things for which this *! function returns the same size, there should be essentially no *! increase in the size of the pike process (some increase might *! occur due to internal fragmentation and memory pooling, but it *! should be small in general and over time). *! *! The search for things only referenced from @[things] can handle *! limited cyclic structures. That is done by doing a "lookahead", *! i.e. searching through referenced things that apparently have *! other outside references. You can control how long this lookahead *! should be through @[options] (see below). If the lookahead is too *! short to cover the cycles in a structure then a too low value is *! returned. If the lookahead is made gradually longer then the *! returned value will eventually become accurate and not increase *! anymore. If the lookahead is too long then unnecessary time might *! be spent searching through things that really have external *! references. *! *! Objects that are known to be part of cyclic structures are *! encouraged to have an integer constant or variable *! @expr{pike_cycle_depth@} that specifies the lookahead needed to *! discover those cycles. When @[Pike.count_memory] visits such *! objects, it uses that as the lookahead when going through the *! references emanating from them. Thus, assuming objects adhere to *! this convention, you should rarely have to specify a lookahead *! higher than zero to this function. *! *! Note that @expr{pike_cycle_depth@} can also be set to zero to *! effectively stop the lookahead from continuing through the object. *! That can be useful to put in objects you know have global *! references, to speed up the traversal. *! *! @param options *! If this is an integer, it specifies the maximum lookahead *! distance. -1 counts only the memory of the given @[things], *! without following any references. 0 extends the count to all *! their referenced things as long as there are no cycles (except *! if @expr{pike_cycle_depth@} is found in objects - see above). 1 *! makes it cover cycles of length 1 (e.g. a thing points to *! itself), 2 handles cycles of length 2 (e.g. where two things *! point at each other), and so on. *! *! However, the lookahead is by default blocked by programs, i.e. *! it never follows references emanating from programs. That since *! programs seldom are part of dynamic data structures, and they *! also typically contain numerous references to global data which *! would add a lot of work to the lookahead search. *! *! To control the search in more detail, @[options] can be a *! mapping instead: *! *! @mapping *! @member int lookahead *! The maximum lookahead distance, as described above. Defaults *! to 0 if missing. *! *! @member int block_arrays *! @member int block_mappings *! @member int block_multisets *! @member int block_objects *! @member int block_programs *! When any of these are given with a nonzero value, the *! corresponding type is blocked when lookahead references are *! followed. They are unblocked if the flag is given with a *! zero value. Only programs are blocked by default. *! *! These blocks are only active during the lookahead, so *! blocked things are still recursed and memory counted if they *! are given as arguments or only got internal references. *! *! @member int block_pike_cycle_depth *! Do not heed @expr{pike_cycle_depth@} values found in *! objects. This is implicit if the lookahead is negative. *! *! @member int return_count *! Return the number of things that memory was counted for, *! instead of the byte count. (This is the same number *! @expr{internal@} contains if @expr{collect_stats@} is set.) *! *! @member int collect_internals *! If this is nonzero then its value is replaced with an array *! that contains the things that memory was counted for. *! *! @member int collect_externals *! If set then the value is replaced with an array containing *! the things that were visited but turned out to have external *! references (within the limited lookahead). *! *! @member int collect_direct_externals *! If set then the value is replaced with an array containing *! the things found during the lookahead that (appears to) have *! direct external references. This list is a subset of the *! @expr{collect_externals@} list. It is useful if you get *! unexpected global references to your data structure which *! you want to track down. *! *! @member int collect_stats *! If this is nonzero then the mapping is extended with more *! elements containing statistics from the search; see below. *! @endmapping *! *! When the @expr{collect_stats@} flag is set, the mapping is *! extended with these elements: *! *! @mapping *! @member int internal *! Number of things that were marked internal and hence memory *! counted. It includes the things given as arguments. *! *! @member int cyclic *! Number of things that were marked internal only after *! resolving cycles. *! *! @member int external *! Number of things that were visited through the lookahead but *! were found to be external. *! *! @member int visits *! Number of times things were visited in total. This figure *! includes visits to various internal things that aren't *! visible from the pike level, so it might be larger than what *! is apparently motivated by the numbers above. *! *! @member int revisits *! Number of times the same things were revisited. This can *! occur in the lookahead when a thing is encountered through a *! shorter path than the one it first got visited through. It *! also occurs in resolved cycles. Like @expr{visits@}, this *! count can include things that aren't visible from pike. *! *! @member int rounds *! Number of search rounds. This is usually 1 or 2. More rounds *! are necessary only when blocked types turn out to be *! (acyclic) internal, so that they need to be counted and *! recursed anyway. *! *! @member int work_queue_alloc *! The number of elements that was allocated to store the work *! queue which is used to keep track of the things to visit *! during the lookahead. This is usually bigger than the *! maximum number of things the queue actually held. *! *! @member int size *! The memory occupied by the internal things. This is the same *! as the normal return value, but it's put here too for *! convenience. *! @endmapping *! *! @param things *! One or more things to count memory size for. Only things passed *! by reference are allowed, except for functions which are *! forbidden because a meaningful size calculation can't be done *! for them. *! *! Integers are allowed because they are bignum objects when they *! become sufficiently large. However, passing an integer that is *! small enough to fit into the native integer type will return *! zero. *! *! @returns *! Returns the number of bytes occupied by the counted things. If *! the @expr{return_count@} option is set then the number of things *! are returned instead. *! *! @note *! The result of @expr{Pike.count_memory(0,a,b)@} might be larger *! than the sum of @expr{Pike.count_memory(0,a)@} and *! @expr{Pike.count_memory(0,b)@} since @expr{a@} and @expr{b@} *! together might reference things that aren't referenced from *! anywhere else. *! *! @note *! It's possible that a string that is referenced still isn't *! counted, because strings are always shared in Pike and the same *! string might be in use in some unrelated part of the program. */ void f_count_memory (INT32 args) { struct svalue *collect_internal = NULL; unsigned count_internal, count_cyclic, count_visited; unsigned count_visits, count_revisits, count_rounds; int collect_stats = 0, return_count = 0; if (args < 1) SIMPLE_TOO_FEW_ARGS_ERROR ("count_memory", 1); mc_block_lookahead = mc_block_lookahead_default; mc_block_pike_cycle_depth = 0; if (Pike_sp[-args].type == T_MAPPING) { struct mapping *opts = Pike_sp[-args].u.mapping; struct pike_string *ind; struct svalue *val; MAKE_CONST_STRING (ind, "lookahead"); if ((val = low_mapping_string_lookup (opts, ind))) { if (val->type != T_INT) SIMPLE_ARG_ERROR ("count_memory", 1, "\"lookahead\" must be an integer."); mc_lookahead = val->u.integer > (unsigned INT16) -1 ? (unsigned INT16) -1 : val->u.integer < 0 ? -1 : val->u.integer; } else mc_lookahead = 0; #define CHECK_BLOCK_FLAG(NAME, TYPE_BIT) do { \ MAKE_CONST_STRING (ind, NAME); \ if ((val = low_mapping_string_lookup (opts, ind))) { \ if (UNSAFE_IS_ZERO (val)) \ mc_block_lookahead &= ~TYPE_BIT; \ else \ mc_block_lookahead |= TYPE_BIT; \ } \ } while (0) CHECK_BLOCK_FLAG ("block_arrays", BIT_ARRAY); CHECK_BLOCK_FLAG ("block_mappings", BIT_MAPPING); CHECK_BLOCK_FLAG ("block_multisets", BIT_MULTISET); CHECK_BLOCK_FLAG ("block_objects", BIT_OBJECT); CHECK_BLOCK_FLAG ("block_programs", BIT_PROGRAM); MAKE_CONST_STRING (ind, "block_pike_cycle_depth"); if ((val = low_mapping_string_lookup (opts, ind)) && !UNSAFE_IS_ZERO (val)) mc_block_pike_cycle_depth = 1; MAKE_CONST_STRING (ind, "return_count"); if ((val = low_mapping_string_lookup (opts, ind)) && !UNSAFE_IS_ZERO (val)) return_count = 1; MAKE_CONST_STRING (ind, "collect_internals"); if ((val = low_mapping_string_lookup (opts, ind)) && !UNSAFE_IS_ZERO (val)) collect_internal = Pike_sp; /* Value doesn't matter. */ MAKE_CONST_STRING (ind, "collect_stats"); if ((val = low_mapping_string_lookup (opts, ind)) && !UNSAFE_IS_ZERO (val)) collect_stats = 1; } else { if (Pike_sp[-args].type != T_INT) SIMPLE_ARG_TYPE_ERROR ("count_memory", 1, "int|mapping(string:int)"); mc_lookahead = Pike_sp[-args].u.integer > (unsigned INT16) -1 ? (unsigned INT16) -1 : Pike_sp[-args].u.integer < 0 ? -1 : Pike_sp[-args].u.integer; } init_mc_marker_hash(); if (pike_cycle_depth_str.type == PIKE_T_FREE) { pike_cycle_depth_str.type = T_STRING; MAKE_CONST_STRING (pike_cycle_depth_str.u.string, "pike_cycle_depth"); } assert (mc_work_queue == NULL); mc_work_queue = malloc (MC_WQ_START_SIZE * sizeof (mc_work_queue[0])); if (!mc_work_queue) { exit_mc_marker_hash(); SIMPLE_OUT_OF_MEMORY_ERROR ("Pike.count_memory", MC_WQ_START_SIZE * sizeof (mc_work_queue[0])); } mc_wq_size = MC_WQ_START_SIZE;

pike.git/ src/ gc.c > 6175593b8a88181e4cb41c91c56a9805798f8f18 [Annotate]