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c35738c1 | 1 | /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002, 2003 Free Software Foundation, Inc. |
a00c95d9 | 2 | * |
73be1d9e MV |
3 | * This library is free software; you can redistribute it and/or |
4 | * modify it under the terms of the GNU Lesser General Public | |
5 | * License as published by the Free Software Foundation; either | |
6 | * version 2.1 of the License, or (at your option) any later version. | |
a00c95d9 | 7 | * |
73be1d9e | 8 | * This library is distributed in the hope that it will be useful, |
0f2d19dd | 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
73be1d9e MV |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
11 | * Lesser General Public License for more details. | |
a00c95d9 | 12 | * |
73be1d9e MV |
13 | * You should have received a copy of the GNU Lesser General Public |
14 | * License along with this library; if not, write to the Free Software | |
15 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
16 | */ | |
1bbd0b84 | 17 | |
1bbd0b84 | 18 | |
37ddcaf6 MD |
19 | /* #define DEBUGINFO */ |
20 | ||
aa54a9b0 RB |
21 | #if HAVE_CONFIG_H |
22 | # include <config.h> | |
23 | #endif | |
56495472 | 24 | |
0f2d19dd | 25 | #include <stdio.h> |
e6e2e95a | 26 | #include <errno.h> |
783e7774 | 27 | #include <string.h> |
c8a1bdc4 | 28 | #include <assert.h> |
e6e2e95a | 29 | |
d9189652 RB |
30 | #ifdef __ia64__ |
31 | #include <ucontext.h> | |
bb1180ef | 32 | extern unsigned long * __libc_ia64_register_backing_store_base; |
d9189652 RB |
33 | #endif |
34 | ||
a0599745 | 35 | #include "libguile/_scm.h" |
0a7a7445 | 36 | #include "libguile/eval.h" |
a0599745 MD |
37 | #include "libguile/stime.h" |
38 | #include "libguile/stackchk.h" | |
39 | #include "libguile/struct.h" | |
a0599745 MD |
40 | #include "libguile/smob.h" |
41 | #include "libguile/unif.h" | |
42 | #include "libguile/async.h" | |
43 | #include "libguile/ports.h" | |
44 | #include "libguile/root.h" | |
45 | #include "libguile/strings.h" | |
46 | #include "libguile/vectors.h" | |
801cb5e7 | 47 | #include "libguile/weaks.h" |
686765af | 48 | #include "libguile/hashtab.h" |
ecf470a2 | 49 | #include "libguile/tags.h" |
a0599745 | 50 | |
c8a1bdc4 | 51 | #include "libguile/private-gc.h" |
a0599745 | 52 | #include "libguile/validate.h" |
1be6b49c | 53 | #include "libguile/deprecation.h" |
a0599745 | 54 | #include "libguile/gc.h" |
fce59c93 | 55 | |
bc9d9bb2 | 56 | #ifdef GUILE_DEBUG_MALLOC |
a0599745 | 57 | #include "libguile/debug-malloc.h" |
bc9d9bb2 MD |
58 | #endif |
59 | ||
0f2d19dd | 60 | #ifdef HAVE_MALLOC_H |
95b88819 | 61 | #include <malloc.h> |
0f2d19dd JB |
62 | #endif |
63 | ||
64 | #ifdef HAVE_UNISTD_H | |
95b88819 | 65 | #include <unistd.h> |
0f2d19dd JB |
66 | #endif |
67 | ||
406c7d90 | 68 | |
8c494e99 | 69 | |
406c7d90 DH |
70 | unsigned int scm_gc_running_p = 0; |
71 | ||
fb50ef08 MD |
72 | /* Lock this mutex before doing lazy sweeping. |
73 | */ | |
76da80e7 | 74 | scm_t_rec_mutex scm_i_sweep_mutex; |
fb50ef08 | 75 | |
eae33935 | 76 | /* Set this to != 0 if every cell that is accessed shall be checked: |
61045190 | 77 | */ |
eab1b259 HWN |
78 | int scm_debug_cell_accesses_p = 0; |
79 | int scm_expensive_debug_cell_accesses_p = 0; | |
406c7d90 | 80 | |
e81d98ec DH |
81 | /* Set this to 0 if no additional gc's shall be performed, otherwise set it to |
82 | * the number of cell accesses after which a gc shall be called. | |
83 | */ | |
eab1b259 | 84 | int scm_debug_cells_gc_interval = 0; |
e81d98ec | 85 | |
eab1b259 HWN |
86 | /* |
87 | Global variable, so you can switch it off at runtime by setting | |
88 | scm_i_cell_validation_already_running. | |
406c7d90 | 89 | */ |
eab1b259 HWN |
90 | int scm_i_cell_validation_already_running ; |
91 | ||
92 | #if (SCM_DEBUG_CELL_ACCESSES == 1) | |
93 | ||
94 | ||
95 | /* | |
96 | ||
97 | Assert that the given object is a valid reference to a valid cell. This | |
98 | test involves to determine whether the object is a cell pointer, whether | |
99 | this pointer actually points into a heap segment and whether the cell | |
100 | pointed to is not a free cell. Further, additional garbage collections may | |
101 | get executed after a user defined number of cell accesses. This helps to | |
102 | find places in the C code where references are dropped for extremely short | |
103 | periods. | |
104 | ||
105 | */ | |
406c7d90 | 106 | void |
eab1b259 | 107 | scm_i_expensive_validation_check (SCM cell) |
406c7d90 | 108 | { |
eab1b259 HWN |
109 | if (!scm_in_heap_p (cell)) |
110 | { | |
111 | fprintf (stderr, "scm_assert_cell_valid: this object does not live in the heap: %lux\n", | |
112 | (unsigned long) SCM_UNPACK (cell)); | |
113 | abort (); | |
114 | } | |
115 | ||
116 | /* If desired, perform additional garbage collections after a user | |
117 | * defined number of cell accesses. | |
118 | */ | |
119 | if (scm_debug_cells_gc_interval) | |
120 | { | |
121 | static unsigned int counter = 0; | |
61045190 | 122 | |
eab1b259 HWN |
123 | if (counter != 0) |
124 | { | |
125 | --counter; | |
126 | } | |
127 | else | |
128 | { | |
129 | counter = scm_debug_cells_gc_interval; | |
130 | scm_igc ("scm_assert_cell_valid"); | |
131 | } | |
132 | } | |
133 | } | |
134 | ||
135 | void | |
136 | scm_assert_cell_valid (SCM cell) | |
137 | { | |
138 | if (!scm_i_cell_validation_already_running && scm_debug_cell_accesses_p) | |
406c7d90 | 139 | { |
eab1b259 | 140 | scm_i_cell_validation_already_running = 1; /* set to avoid recursion */ |
406c7d90 | 141 | |
c8a1bdc4 | 142 | /* |
eab1b259 HWN |
143 | During GC, no user-code should be run, and the guile core |
144 | should use non-protected accessors. | |
145 | */ | |
c8a1bdc4 | 146 | if (scm_gc_running_p) |
eab1b259 | 147 | return; |
c8a1bdc4 HWN |
148 | |
149 | /* | |
eab1b259 HWN |
150 | Only scm_in_heap_p and rescanning the heap is wildly |
151 | expensive. | |
152 | */ | |
153 | if (scm_expensive_debug_cell_accesses_p) | |
154 | scm_i_expensive_validation_check (cell); | |
c8a1bdc4 HWN |
155 | |
156 | if (!SCM_GC_MARK_P (cell)) | |
406c7d90 | 157 | { |
c8a1bdc4 HWN |
158 | fprintf (stderr, |
159 | "scm_assert_cell_valid: this object is unmarked. \n" | |
160 | "It has been garbage-collected in the last GC run: " | |
161 | "%lux\n", | |
1be6b49c | 162 | (unsigned long) SCM_UNPACK (cell)); |
406c7d90 DH |
163 | abort (); |
164 | } | |
c8a1bdc4 | 165 | |
eab1b259 | 166 | scm_i_cell_validation_already_running = 0; /* re-enable */ |
406c7d90 DH |
167 | } |
168 | } | |
169 | ||
170 | ||
eab1b259 | 171 | |
406c7d90 DH |
172 | SCM_DEFINE (scm_set_debug_cell_accesses_x, "set-debug-cell-accesses!", 1, 0, 0, |
173 | (SCM flag), | |
1e6808ea | 174 | "If @var{flag} is @code{#f}, cell access checking is disabled.\n" |
eab1b259 | 175 | "If @var{flag} is @code{#t}, cheap cell access checking is enabled,\n" |
e81d98ec | 176 | "but no additional calls to garbage collection are issued.\n" |
eab1b259 | 177 | "If @var{flag} is a number, strict cell access checking is enabled,\n" |
e81d98ec DH |
178 | "with an additional garbage collection after the given\n" |
179 | "number of cell accesses.\n" | |
1e6808ea MG |
180 | "This procedure only exists when the compile-time flag\n" |
181 | "@code{SCM_DEBUG_CELL_ACCESSES} was set to 1.") | |
406c7d90 DH |
182 | #define FUNC_NAME s_scm_set_debug_cell_accesses_x |
183 | { | |
7888309b | 184 | if (scm_is_false (flag)) |
eab1b259 HWN |
185 | { |
186 | scm_debug_cell_accesses_p = 0; | |
187 | } | |
bc36d050 | 188 | else if (scm_is_eq (flag, SCM_BOOL_T)) |
eab1b259 HWN |
189 | { |
190 | scm_debug_cells_gc_interval = 0; | |
191 | scm_debug_cell_accesses_p = 1; | |
192 | scm_expensive_debug_cell_accesses_p = 0; | |
193 | } | |
e11e83f3 | 194 | else |
eab1b259 | 195 | { |
e11e83f3 | 196 | scm_debug_cells_gc_interval = scm_to_signed_integer (flag, 0, INT_MAX); |
eab1b259 HWN |
197 | scm_debug_cell_accesses_p = 1; |
198 | scm_expensive_debug_cell_accesses_p = 1; | |
199 | } | |
406c7d90 DH |
200 | return SCM_UNSPECIFIED; |
201 | } | |
202 | #undef FUNC_NAME | |
0f2d19dd | 203 | |
ecf470a2 | 204 | |
c8a1bdc4 | 205 | #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */ |
0f2d19dd JB |
206 | |
207 | \f | |
945fec60 | 208 | |
76da80e7 MV |
209 | scm_t_key scm_i_freelist; |
210 | scm_t_key scm_i_freelist2; | |
211 | ||
0f2d19dd JB |
212 | |
213 | /* scm_mtrigger | |
539b08a4 | 214 | * is the number of bytes of malloc allocation needed to trigger gc. |
0f2d19dd | 215 | */ |
c014a02e | 216 | unsigned long scm_mtrigger; |
0f2d19dd | 217 | |
0f2d19dd JB |
218 | /* scm_gc_heap_lock |
219 | * If set, don't expand the heap. Set only during gc, during which no allocation | |
220 | * is supposed to take place anyway. | |
221 | */ | |
222 | int scm_gc_heap_lock = 0; | |
223 | ||
224 | /* GC Blocking | |
225 | * Don't pause for collection if this is set -- just | |
226 | * expand the heap. | |
227 | */ | |
0f2d19dd JB |
228 | int scm_block_gc = 1; |
229 | ||
0f2d19dd JB |
230 | /* During collection, this accumulates objects holding |
231 | * weak references. | |
232 | */ | |
ab4bef85 | 233 | SCM scm_weak_vectors; |
0f2d19dd JB |
234 | |
235 | /* GC Statistics Keeping | |
236 | */ | |
f2893a25 | 237 | unsigned long scm_cells_allocated = 0; |
c014a02e ML |
238 | unsigned long scm_mallocated = 0; |
239 | unsigned long scm_gc_cells_collected; | |
c8a1bdc4 | 240 | unsigned long scm_gc_cells_collected_1 = 0; /* previous GC yield */ |
c014a02e ML |
241 | unsigned long scm_gc_malloc_collected; |
242 | unsigned long scm_gc_ports_collected; | |
0f2d19dd | 243 | unsigned long scm_gc_time_taken = 0; |
c014a02e | 244 | static unsigned long t_before_gc; |
c9b0d4b0 | 245 | unsigned long scm_gc_mark_time_taken = 0; |
c014a02e ML |
246 | unsigned long scm_gc_times = 0; |
247 | unsigned long scm_gc_cells_swept = 0; | |
c9b0d4b0 ML |
248 | double scm_gc_cells_marked_acc = 0.; |
249 | double scm_gc_cells_swept_acc = 0.; | |
c2cbcc57 HWN |
250 | int scm_gc_cell_yield_percentage =0; |
251 | int scm_gc_malloc_yield_percentage = 0; | |
7eec4c37 | 252 | unsigned long protected_obj_count = 0; |
c2cbcc57 | 253 | |
0f2d19dd JB |
254 | |
255 | SCM_SYMBOL (sym_cells_allocated, "cells-allocated"); | |
256 | SCM_SYMBOL (sym_heap_size, "cell-heap-size"); | |
257 | SCM_SYMBOL (sym_mallocated, "bytes-malloced"); | |
258 | SCM_SYMBOL (sym_mtrigger, "gc-malloc-threshold"); | |
259 | SCM_SYMBOL (sym_heap_segments, "cell-heap-segments"); | |
260 | SCM_SYMBOL (sym_gc_time_taken, "gc-time-taken"); | |
c9b0d4b0 | 261 | SCM_SYMBOL (sym_gc_mark_time_taken, "gc-mark-time-taken"); |
c9b0d4b0 ML |
262 | SCM_SYMBOL (sym_times, "gc-times"); |
263 | SCM_SYMBOL (sym_cells_marked, "cells-marked"); | |
264 | SCM_SYMBOL (sym_cells_swept, "cells-swept"); | |
c2cbcc57 HWN |
265 | SCM_SYMBOL (sym_malloc_yield, "malloc-yield"); |
266 | SCM_SYMBOL (sym_cell_yield, "cell-yield"); | |
7eec4c37 | 267 | SCM_SYMBOL (sym_protected_objects, "protected-objects"); |
0f2d19dd | 268 | |
bb2c57fa | 269 | |
cf2d30f6 | 270 | |
d3dd80ab | 271 | |
cf2d30f6 | 272 | /* Number of calls to SCM_NEWCELL since startup. */ |
c8a1bdc4 HWN |
273 | unsigned scm_newcell_count; |
274 | unsigned scm_newcell2_count; | |
b37fe1c5 | 275 | |
b37fe1c5 | 276 | |
0f2d19dd JB |
277 | /* {Scheme Interface to GC} |
278 | */ | |
1367aa5e HWN |
279 | static SCM |
280 | tag_table_to_type_alist (void *closure, SCM key, SCM val, SCM acc) | |
281 | { | |
282 | scm_t_bits c_tag = scm_to_int (key); | |
283 | key = scm_from_locale_string (scm_i_tag_name (c_tag)); | |
284 | return scm_cons (scm_cons (key, val), acc); | |
285 | } | |
286 | ||
287 | SCM_DEFINE (scm_gc_live_object_stats, "gc-live-object-stats", 0, 0, 0, | |
288 | (), | |
289 | "Return an alist of statistics of the current live objects. ") | |
290 | #define FUNC_NAME s_scm_gc_live_object_stats | |
291 | { | |
292 | SCM tab = scm_make_hash_table (scm_from_int (57)); | |
293 | scm_i_all_segments_statistics (tab); | |
294 | ||
295 | SCM alist | |
296 | = scm_internal_hash_fold (&tag_table_to_type_alist, NULL, SCM_EOL, tab); | |
297 | ||
298 | return alist; | |
299 | } | |
300 | #undef FUNC_NAME | |
301 | ||
c2cbcc57 | 302 | extern int scm_gc_malloc_yield_percentage; |
a00c95d9 | 303 | SCM_DEFINE (scm_gc_stats, "gc-stats", 0, 0, 0, |
1bbd0b84 | 304 | (), |
1e6808ea | 305 | "Return an association list of statistics about Guile's current\n" |
c8a1bdc4 | 306 | "use of storage.\n") |
1bbd0b84 | 307 | #define FUNC_NAME s_scm_gc_stats |
0f2d19dd | 308 | { |
c8a1bdc4 HWN |
309 | long i = 0; |
310 | SCM heap_segs = SCM_EOL ; | |
c014a02e ML |
311 | unsigned long int local_scm_mtrigger; |
312 | unsigned long int local_scm_mallocated; | |
313 | unsigned long int local_scm_heap_size; | |
c2cbcc57 HWN |
314 | int local_scm_gc_cell_yield_percentage; |
315 | int local_scm_gc_malloc_yield_percentage; | |
f2893a25 | 316 | unsigned long int local_scm_cells_allocated; |
c014a02e ML |
317 | unsigned long int local_scm_gc_time_taken; |
318 | unsigned long int local_scm_gc_times; | |
319 | unsigned long int local_scm_gc_mark_time_taken; | |
7eec4c37 | 320 | unsigned long int local_protected_obj_count; |
c9b0d4b0 ML |
321 | double local_scm_gc_cells_swept; |
322 | double local_scm_gc_cells_marked; | |
0f2d19dd | 323 | SCM answer; |
c8a1bdc4 HWN |
324 | unsigned long *bounds = 0; |
325 | int table_size = scm_i_heap_segment_table_size; | |
0f2d19dd | 326 | SCM_DEFER_INTS; |
939794ce | 327 | |
c8a1bdc4 HWN |
328 | /* |
329 | temporarily store the numbers, so as not to cause GC. | |
7febb4a2 | 330 | */ |
c8a1bdc4 HWN |
331 | |
332 | bounds = malloc (sizeof (int) * table_size * 2); | |
333 | if (!bounds) | |
334 | abort(); | |
335 | for (i = table_size; i--; ) | |
336 | { | |
337 | bounds[2*i] = (unsigned long)scm_i_heap_segment_table[i]->bounds[0]; | |
338 | bounds[2*i+1] = (unsigned long)scm_i_heap_segment_table[i]->bounds[1]; | |
339 | } | |
0f2d19dd | 340 | |
4c9419ac | 341 | |
c8a1bdc4 HWN |
342 | /* Below, we cons to produce the resulting list. We want a snapshot of |
343 | * the heap situation before consing. | |
344 | */ | |
345 | local_scm_mtrigger = scm_mtrigger; | |
346 | local_scm_mallocated = scm_mallocated; | |
347 | local_scm_heap_size = SCM_HEAP_SIZE; | |
539b08a4 | 348 | |
c8a1bdc4 HWN |
349 | local_scm_cells_allocated = scm_cells_allocated; |
350 | ||
351 | local_scm_gc_time_taken = scm_gc_time_taken; | |
352 | local_scm_gc_mark_time_taken = scm_gc_mark_time_taken; | |
353 | local_scm_gc_times = scm_gc_times; | |
c2cbcc57 HWN |
354 | local_scm_gc_malloc_yield_percentage = scm_gc_malloc_yield_percentage; |
355 | local_scm_gc_cell_yield_percentage= scm_gc_cell_yield_percentage; | |
7eec4c37 | 356 | local_protected_obj_count = protected_obj_count; |
c2cbcc57 HWN |
357 | local_scm_gc_cells_swept = |
358 | (double) scm_gc_cells_swept_acc | |
359 | + (double) scm_gc_cells_swept; | |
c8a1bdc4 HWN |
360 | local_scm_gc_cells_marked = scm_gc_cells_marked_acc |
361 | +(double) scm_gc_cells_swept | |
362 | -(double) scm_gc_cells_collected; | |
0f2d19dd | 363 | |
c8a1bdc4 HWN |
364 | for (i = table_size; i--;) |
365 | { | |
b9bd8526 MV |
366 | heap_segs = scm_cons (scm_cons (scm_from_ulong (bounds[2*i]), |
367 | scm_from_ulong (bounds[2*i+1])), | |
c8a1bdc4 HWN |
368 | heap_segs); |
369 | } | |
370 | ||
b9bd8526 MV |
371 | answer = |
372 | scm_list_n (scm_cons (sym_gc_time_taken, | |
373 | scm_from_ulong (local_scm_gc_time_taken)), | |
374 | scm_cons (sym_cells_allocated, | |
375 | scm_from_ulong (local_scm_cells_allocated)), | |
376 | scm_cons (sym_heap_size, | |
377 | scm_from_ulong (local_scm_heap_size)), | |
378 | scm_cons (sym_mallocated, | |
379 | scm_from_ulong (local_scm_mallocated)), | |
380 | scm_cons (sym_mtrigger, | |
381 | scm_from_ulong (local_scm_mtrigger)), | |
382 | scm_cons (sym_times, | |
383 | scm_from_ulong (local_scm_gc_times)), | |
384 | scm_cons (sym_gc_mark_time_taken, | |
385 | scm_from_ulong (local_scm_gc_mark_time_taken)), | |
386 | scm_cons (sym_cells_marked, | |
387 | scm_from_double (local_scm_gc_cells_marked)), | |
388 | scm_cons (sym_cells_swept, | |
389 | scm_from_double (local_scm_gc_cells_swept)), | |
390 | scm_cons (sym_malloc_yield, | |
391 | scm_from_long(local_scm_gc_malloc_yield_percentage)), | |
392 | scm_cons (sym_cell_yield, | |
393 | scm_from_long (local_scm_gc_cell_yield_percentage)), | |
394 | scm_cons (sym_protected_objects, | |
395 | scm_from_ulong (local_protected_obj_count)), | |
396 | scm_cons (sym_heap_segments, heap_segs), | |
397 | SCM_UNDEFINED); | |
c8a1bdc4 HWN |
398 | SCM_ALLOW_INTS; |
399 | ||
400 | free (bounds); | |
401 | return answer; | |
0f2d19dd | 402 | } |
c8a1bdc4 | 403 | #undef FUNC_NAME |
0f2d19dd | 404 | |
c8a1bdc4 HWN |
405 | static void |
406 | gc_start_stats (const char *what SCM_UNUSED) | |
e4a7824f | 407 | { |
c8a1bdc4 | 408 | t_before_gc = scm_c_get_internal_run_time (); |
539b08a4 | 409 | |
c8a1bdc4 HWN |
410 | scm_gc_cells_marked_acc += (double) scm_gc_cells_swept |
411 | - (double) scm_gc_cells_collected; | |
c2cbcc57 | 412 | scm_gc_cells_swept_acc += (double) scm_gc_cells_swept; |
e4a7824f | 413 | |
c2cbcc57 HWN |
414 | scm_gc_cell_yield_percentage = ( scm_gc_cells_collected * 100 ) / SCM_HEAP_SIZE; |
415 | ||
c8a1bdc4 HWN |
416 | scm_gc_cells_swept = 0; |
417 | scm_gc_cells_collected_1 = scm_gc_cells_collected; | |
539b08a4 | 418 | |
c8a1bdc4 HWN |
419 | /* |
420 | CELLS SWEPT is another word for the number of cells that were | |
421 | examined during GC. YIELD is the number that we cleaned | |
422 | out. MARKED is the number that weren't cleaned. | |
423 | */ | |
424 | scm_gc_cells_collected = 0; | |
425 | scm_gc_malloc_collected = 0; | |
426 | scm_gc_ports_collected = 0; | |
e4a7824f | 427 | } |
acf4331f | 428 | |
c8a1bdc4 HWN |
429 | static void |
430 | gc_end_stats () | |
0f2d19dd | 431 | { |
c8a1bdc4 HWN |
432 | unsigned long t = scm_c_get_internal_run_time (); |
433 | scm_gc_time_taken += (t - t_before_gc); | |
539b08a4 | 434 | |
c8a1bdc4 | 435 | ++scm_gc_times; |
0f2d19dd | 436 | } |
acf4331f | 437 | |
0f2d19dd | 438 | |
c8a1bdc4 HWN |
439 | SCM_DEFINE (scm_object_address, "object-address", 1, 0, 0, |
440 | (SCM obj), | |
441 | "Return an integer that for the lifetime of @var{obj} is uniquely\n" | |
442 | "returned by this function for @var{obj}") | |
443 | #define FUNC_NAME s_scm_object_address | |
c68296f8 | 444 | { |
b9bd8526 | 445 | return scm_from_ulong (SCM_UNPACK (obj)); |
c68296f8 | 446 | } |
c8a1bdc4 | 447 | #undef FUNC_NAME |
c68296f8 | 448 | |
1be6b49c | 449 | |
c8a1bdc4 HWN |
450 | SCM_DEFINE (scm_gc, "gc", 0, 0, 0, |
451 | (), | |
452 | "Scans all of SCM objects and reclaims for further use those that are\n" | |
453 | "no longer accessible.") | |
454 | #define FUNC_NAME s_scm_gc | |
455 | { | |
c8a1bdc4 | 456 | scm_igc ("call"); |
c8a1bdc4 | 457 | return SCM_UNSPECIFIED; |
9d47a1e6 | 458 | } |
c8a1bdc4 | 459 | #undef FUNC_NAME |
9d47a1e6 | 460 | |
c68296f8 MV |
461 | |
462 | \f | |
0f2d19dd | 463 | |
c8a1bdc4 HWN |
464 | /* When we get POSIX threads support, the master will be global and |
465 | * common while the freelist will be individual for each thread. | |
0f2d19dd JB |
466 | */ |
467 | ||
c8a1bdc4 HWN |
468 | SCM |
469 | scm_gc_for_newcell (scm_t_cell_type_statistics *freelist, SCM *free_cells) | |
0f2d19dd | 470 | { |
c8a1bdc4 HWN |
471 | SCM cell; |
472 | ||
76da80e7 | 473 | scm_rec_mutex_lock (&scm_i_sweep_mutex); |
9bc4701c | 474 | |
c8a1bdc4 HWN |
475 | *free_cells = scm_i_sweep_some_segments (freelist); |
476 | if (*free_cells == SCM_EOL && scm_i_gc_grow_heap_p (freelist)) | |
477 | { | |
478 | freelist->heap_segment_idx = scm_i_get_new_heap_segment (freelist, abort_on_error); | |
479 | *free_cells = scm_i_sweep_some_segments (freelist); | |
480 | } | |
acb0a19c | 481 | |
c8a1bdc4 HWN |
482 | if (*free_cells == SCM_EOL && !scm_block_gc) |
483 | { | |
484 | /* | |
485 | with the advent of lazy sweep, GC yield is only know just | |
486 | before doing the GC. | |
487 | */ | |
488 | scm_i_adjust_min_yield (freelist); | |
489 | ||
490 | /* | |
491 | out of fresh cells. Try to get some new ones. | |
492 | */ | |
0f2d19dd | 493 | |
c8a1bdc4 | 494 | scm_igc ("cells"); |
a00c95d9 | 495 | |
c8a1bdc4 HWN |
496 | *free_cells = scm_i_sweep_some_segments (freelist); |
497 | } | |
498 | ||
499 | if (*free_cells == SCM_EOL) | |
500 | { | |
501 | /* | |
502 | failed getting new cells. Get new juice or die. | |
503 | */ | |
504 | freelist->heap_segment_idx = scm_i_get_new_heap_segment (freelist, abort_on_error); | |
505 | *free_cells = scm_i_sweep_some_segments (freelist); | |
506 | } | |
507 | ||
508 | if (*free_cells == SCM_EOL) | |
509 | abort (); | |
0f2d19dd | 510 | |
c8a1bdc4 | 511 | cell = *free_cells; |
0f2d19dd | 512 | |
c8a1bdc4 | 513 | *free_cells = SCM_FREE_CELL_CDR (cell); |
eab1b259 | 514 | |
76da80e7 | 515 | scm_rec_mutex_unlock (&scm_i_sweep_mutex); |
eab1b259 | 516 | |
c8a1bdc4 HWN |
517 | return cell; |
518 | } | |
4a4c9785 | 519 | |
4a4c9785 | 520 | |
c8a1bdc4 HWN |
521 | scm_t_c_hook scm_before_gc_c_hook; |
522 | scm_t_c_hook scm_before_mark_c_hook; | |
523 | scm_t_c_hook scm_before_sweep_c_hook; | |
524 | scm_t_c_hook scm_after_sweep_c_hook; | |
525 | scm_t_c_hook scm_after_gc_c_hook; | |
4a4c9785 | 526 | |
c8a1bdc4 HWN |
527 | void |
528 | scm_igc (const char *what) | |
529 | { | |
76da80e7 | 530 | scm_rec_mutex_lock (&scm_i_sweep_mutex); |
c8a1bdc4 HWN |
531 | ++scm_gc_running_p; |
532 | scm_c_hook_run (&scm_before_gc_c_hook, 0); | |
a00c95d9 | 533 | |
c8a1bdc4 HWN |
534 | #ifdef DEBUGINFO |
535 | fprintf (stderr,"gc reason %s\n", what); | |
536 | ||
537 | fprintf (stderr, | |
d2e53ed6 | 538 | scm_is_null (*SCM_FREELIST_LOC (scm_i_freelist)) |
c8a1bdc4 | 539 | ? "*" |
d2e53ed6 | 540 | : (scm_is_null (*SCM_FREELIST_LOC (scm_i_freelist2)) ? "o" : "m")); |
c8a1bdc4 | 541 | #endif |
4c48ba06 | 542 | |
c8a1bdc4 | 543 | /* During the critical section, only the current thread may run. */ |
fb50ef08 | 544 | scm_i_thread_put_to_sleep (); |
a00c95d9 | 545 | |
eab1b259 | 546 | if (!scm_root || !scm_stack_base || scm_block_gc) |
d6884e63 | 547 | { |
c8a1bdc4 HWN |
548 | --scm_gc_running_p; |
549 | return; | |
d6884e63 ML |
550 | } |
551 | ||
c8a1bdc4 | 552 | gc_start_stats (what); |
a00c95d9 | 553 | |
1367aa5e HWN |
554 | |
555 | ||
c8a1bdc4 HWN |
556 | if (scm_gc_heap_lock) |
557 | /* We've invoked the collector while a GC is already in progress. | |
558 | That should never happen. */ | |
559 | abort (); | |
a00c95d9 | 560 | |
1367aa5e HWN |
561 | /* |
562 | Set freelists to NULL so scm_cons() always triggers gc, causing | |
563 | the above abort() to be triggered. | |
564 | */ | |
565 | *SCM_FREELIST_LOC (scm_i_freelist) = SCM_EOL; | |
566 | *SCM_FREELIST_LOC (scm_i_freelist2) = SCM_EOL; | |
567 | ||
c8a1bdc4 | 568 | ++scm_gc_heap_lock; |
a00c95d9 | 569 | |
c8a1bdc4 HWN |
570 | /* |
571 | Let's finish the sweep. The conservative GC might point into the | |
572 | garbage, and marking that would create a mess. | |
573 | */ | |
574 | scm_i_sweep_all_segments("GC"); | |
575 | if (scm_mallocated < scm_i_deprecated_memory_return) | |
b6efc951 | 576 | { |
c8a1bdc4 HWN |
577 | /* The byte count of allocated objects has underflowed. This is |
578 | probably because you forgot to report the sizes of objects you | |
579 | have allocated, by calling scm_done_malloc or some such. When | |
580 | the GC freed them, it subtracted their size from | |
581 | scm_mallocated, which underflowed. */ | |
582 | fprintf (stderr, | |
583 | "scm_gc_sweep: Byte count of allocated objects has underflowed.\n" | |
584 | "This is probably because the GC hasn't been correctly informed\n" | |
585 | "about object sizes\n"); | |
b6efc951 DH |
586 | abort (); |
587 | } | |
c8a1bdc4 | 588 | scm_mallocated -= scm_i_deprecated_memory_return; |
0f2d19dd | 589 | |
c8a1bdc4 HWN |
590 | |
591 | ||
592 | scm_c_hook_run (&scm_before_mark_c_hook, 0); | |
b6efc951 | 593 | |
c8a1bdc4 HWN |
594 | scm_mark_all (); |
595 | ||
c2cbcc57 | 596 | scm_gc_mark_time_taken += (scm_c_get_internal_run_time () - t_before_gc); |
c8a1bdc4 HWN |
597 | |
598 | scm_c_hook_run (&scm_before_sweep_c_hook, 0); | |
599 | ||
600 | /* | |
601 | Moved this lock upwards so that we can alloc new heap at the end of a sweep. | |
0f2d19dd | 602 | |
c8a1bdc4 | 603 | DOCME: why should the heap be locked anyway? |
0f2d19dd | 604 | */ |
c8a1bdc4 | 605 | --scm_gc_heap_lock; |
a00c95d9 | 606 | |
c8a1bdc4 | 607 | scm_gc_sweep (); |
0f2d19dd | 608 | |
ffd72400 HWN |
609 | |
610 | /* | |
611 | TODO: this hook should probably be moved to just before the mark, | |
612 | since that's where the sweep is finished in lazy sweeping. | |
c35738c1 MD |
613 | |
614 | MDJ 030219 <djurfeldt@nada.kth.se>: No, probably not. The | |
615 | original meaning implied at least two things: that it would be | |
616 | called when | |
617 | ||
618 | 1. the freelist is re-initialized (no evaluation possible, though) | |
619 | ||
620 | and | |
621 | ||
622 | 2. the heap is "fresh" | |
623 | (it is well-defined what data is used and what is not) | |
624 | ||
625 | Neither of these conditions would hold just before the mark phase. | |
626 | ||
627 | Of course, the lazy sweeping has muddled the distinction between | |
628 | scm_before_sweep_c_hook and scm_after_sweep_c_hook, but even if | |
629 | there were no difference, it would still be useful to have two | |
630 | distinct classes of hook functions since this can prevent some | |
631 | bad interference when several modules adds gc hooks. | |
ffd72400 | 632 | */ |
c8a1bdc4 HWN |
633 | scm_c_hook_run (&scm_after_sweep_c_hook, 0); |
634 | gc_end_stats (); | |
635 | ||
fb50ef08 | 636 | scm_i_thread_wake_up (); |
ffd72400 HWN |
637 | |
638 | /* | |
639 | See above. | |
640 | */ | |
c8a1bdc4 | 641 | --scm_gc_running_p; |
07b99edb | 642 | scm_c_hook_run (&scm_after_gc_c_hook, 0); |
76da80e7 | 643 | scm_rec_mutex_unlock (&scm_i_sweep_mutex); |
a00c95d9 | 644 | |
eab1b259 HWN |
645 | /* |
646 | For debugging purposes, you could do | |
647 | scm_i_sweep_all_segments("debug"), but then the remains of the | |
648 | cell aren't left to analyse. | |
649 | */ | |
650 | } | |
0f2d19dd | 651 | |
0f2d19dd JB |
652 | \f |
653 | /* {GC Protection Helper Functions} | |
654 | */ | |
655 | ||
656 | ||
5d2b97cd DH |
657 | /* |
658 | * If within a function you need to protect one or more scheme objects from | |
659 | * garbage collection, pass them as parameters to one of the | |
660 | * scm_remember_upto_here* functions below. These functions don't do | |
661 | * anything, but since the compiler does not know that they are actually | |
662 | * no-ops, it will generate code that calls these functions with the given | |
663 | * parameters. Therefore, you can be sure that the compiler will keep those | |
664 | * scheme values alive (on the stack or in a register) up to the point where | |
665 | * scm_remember_upto_here* is called. In other words, place the call to | |
592996c9 | 666 | * scm_remember_upto_here* _behind_ the last code in your function, that |
5d2b97cd DH |
667 | * depends on the scheme object to exist. |
668 | * | |
8c494e99 DH |
669 | * Example: We want to make sure that the string object str does not get |
670 | * garbage collected during the execution of 'some_function' in the code | |
671 | * below, because otherwise the characters belonging to str would be freed and | |
5d2b97cd DH |
672 | * 'some_function' might access freed memory. To make sure that the compiler |
673 | * keeps str alive on the stack or in a register such that it is visible to | |
674 | * the conservative gc we add the call to scm_remember_upto_here_1 _after_ the | |
675 | * call to 'some_function'. Note that this would not be necessary if str was | |
676 | * used anyway after the call to 'some_function'. | |
eb01cb64 | 677 | * char *chars = scm_i_string_chars (str); |
5d2b97cd DH |
678 | * some_function (chars); |
679 | * scm_remember_upto_here_1 (str); // str will be alive up to this point. | |
680 | */ | |
681 | ||
9e1569bd KR |
682 | /* Remove any macro versions of these while defining the functions. |
683 | Functions are always included in the library, for upward binary | |
684 | compatibility and in case combinations of GCC and non-GCC are used. */ | |
685 | #undef scm_remember_upto_here_1 | |
686 | #undef scm_remember_upto_here_2 | |
687 | ||
5d2b97cd | 688 | void |
e81d98ec | 689 | scm_remember_upto_here_1 (SCM obj SCM_UNUSED) |
5d2b97cd DH |
690 | { |
691 | /* Empty. Protects a single object from garbage collection. */ | |
692 | } | |
693 | ||
694 | void | |
e81d98ec | 695 | scm_remember_upto_here_2 (SCM obj1 SCM_UNUSED, SCM obj2 SCM_UNUSED) |
5d2b97cd DH |
696 | { |
697 | /* Empty. Protects two objects from garbage collection. */ | |
698 | } | |
699 | ||
700 | void | |
e81d98ec | 701 | scm_remember_upto_here (SCM obj SCM_UNUSED, ...) |
5d2b97cd DH |
702 | { |
703 | /* Empty. Protects any number of objects from garbage collection. */ | |
704 | } | |
705 | ||
c209c88e | 706 | /* |
41b0806d GB |
707 | These crazy functions prevent garbage collection |
708 | of arguments after the first argument by | |
709 | ensuring they remain live throughout the | |
710 | function because they are used in the last | |
711 | line of the code block. | |
712 | It'd be better to have a nice compiler hint to | |
713 | aid the conservative stack-scanning GC. --03/09/00 gjb */ | |
0f2d19dd JB |
714 | SCM |
715 | scm_return_first (SCM elt, ...) | |
0f2d19dd JB |
716 | { |
717 | return elt; | |
718 | } | |
719 | ||
41b0806d GB |
720 | int |
721 | scm_return_first_int (int i, ...) | |
722 | { | |
723 | return i; | |
724 | } | |
725 | ||
0f2d19dd | 726 | |
0f2d19dd | 727 | SCM |
6e8d25a6 | 728 | scm_permanent_object (SCM obj) |
0f2d19dd JB |
729 | { |
730 | SCM_REDEFER_INTS; | |
731 | scm_permobjs = scm_cons (obj, scm_permobjs); | |
732 | SCM_REALLOW_INTS; | |
733 | return obj; | |
734 | } | |
735 | ||
736 | ||
7bd4fbe2 MD |
737 | /* Protect OBJ from the garbage collector. OBJ will not be freed, even if all |
738 | other references are dropped, until the object is unprotected by calling | |
6b1b030e | 739 | scm_gc_unprotect_object (OBJ). Calls to scm_gc_protect/unprotect_object nest, |
7bd4fbe2 MD |
740 | i. e. it is possible to protect the same object several times, but it is |
741 | necessary to unprotect the object the same number of times to actually get | |
742 | the object unprotected. It is an error to unprotect an object more often | |
743 | than it has been protected before. The function scm_protect_object returns | |
744 | OBJ. | |
745 | */ | |
746 | ||
747 | /* Implementation note: For every object X, there is a counter which | |
6b1b030e | 748 | scm_gc_protect_object(X) increments and scm_gc_unprotect_object(X) decrements. |
7bd4fbe2 | 749 | */ |
686765af | 750 | |
7eec4c37 HWN |
751 | |
752 | ||
ef290276 | 753 | SCM |
6b1b030e | 754 | scm_gc_protect_object (SCM obj) |
ef290276 | 755 | { |
686765af | 756 | SCM handle; |
9d47a1e6 | 757 | |
686765af | 758 | /* This critical section barrier will be replaced by a mutex. */ |
2dd6a83a | 759 | SCM_REDEFER_INTS; |
9d47a1e6 | 760 | |
e11e83f3 MV |
761 | handle = scm_hashq_create_handle_x (scm_protects, obj, scm_from_int (0)); |
762 | SCM_SETCDR (handle, scm_sum (SCM_CDR (handle), scm_from_int (1))); | |
9d47a1e6 | 763 | |
7eec4c37 HWN |
764 | protected_obj_count ++; |
765 | ||
2dd6a83a | 766 | SCM_REALLOW_INTS; |
9d47a1e6 | 767 | |
ef290276 JB |
768 | return obj; |
769 | } | |
770 | ||
771 | ||
772 | /* Remove any protection for OBJ established by a prior call to | |
dab7f566 | 773 | scm_protect_object. This function returns OBJ. |
ef290276 | 774 | |
dab7f566 | 775 | See scm_protect_object for more information. */ |
ef290276 | 776 | SCM |
6b1b030e | 777 | scm_gc_unprotect_object (SCM obj) |
ef290276 | 778 | { |
686765af | 779 | SCM handle; |
9d47a1e6 | 780 | |
686765af | 781 | /* This critical section barrier will be replaced by a mutex. */ |
2dd6a83a | 782 | SCM_REDEFER_INTS; |
9d47a1e6 | 783 | |
0ff7e3ff HWN |
784 | if (scm_gc_running_p) |
785 | { | |
786 | fprintf (stderr, "scm_unprotect_object called during GC.\n"); | |
787 | abort (); | |
788 | } | |
789 | ||
686765af | 790 | handle = scm_hashq_get_handle (scm_protects, obj); |
9d47a1e6 | 791 | |
7888309b | 792 | if (scm_is_false (handle)) |
686765af | 793 | { |
0f0f0899 MD |
794 | fprintf (stderr, "scm_unprotect_object called on unprotected object\n"); |
795 | abort (); | |
686765af | 796 | } |
6a199940 DH |
797 | else |
798 | { | |
e11e83f3 | 799 | SCM count = scm_difference (SCM_CDR (handle), scm_from_int (1)); |
bc36d050 | 800 | if (scm_is_eq (count, scm_from_int (0))) |
6a199940 DH |
801 | scm_hashq_remove_x (scm_protects, obj); |
802 | else | |
1be6b49c | 803 | SCM_SETCDR (handle, count); |
6a199940 | 804 | } |
7eec4c37 | 805 | protected_obj_count --; |
686765af | 806 | |
2dd6a83a | 807 | SCM_REALLOW_INTS; |
ef290276 JB |
808 | |
809 | return obj; | |
810 | } | |
811 | ||
6b1b030e ML |
812 | void |
813 | scm_gc_register_root (SCM *p) | |
814 | { | |
815 | SCM handle; | |
b9bd8526 | 816 | SCM key = scm_from_ulong ((unsigned long) p); |
eae33935 | 817 | |
6b1b030e ML |
818 | /* This critical section barrier will be replaced by a mutex. */ |
819 | SCM_REDEFER_INTS; | |
820 | ||
e11e83f3 MV |
821 | handle = scm_hashv_create_handle_x (scm_gc_registered_roots, key, |
822 | scm_from_int (0)); | |
823 | SCM_SETCDR (handle, scm_sum (SCM_CDR (handle), scm_from_int (1))); | |
6b1b030e ML |
824 | |
825 | SCM_REALLOW_INTS; | |
826 | } | |
827 | ||
828 | void | |
829 | scm_gc_unregister_root (SCM *p) | |
830 | { | |
831 | SCM handle; | |
b9bd8526 | 832 | SCM key = scm_from_ulong ((unsigned long) p); |
6b1b030e ML |
833 | |
834 | /* This critical section barrier will be replaced by a mutex. */ | |
835 | SCM_REDEFER_INTS; | |
836 | ||
837 | handle = scm_hashv_get_handle (scm_gc_registered_roots, key); | |
838 | ||
7888309b | 839 | if (scm_is_false (handle)) |
6b1b030e ML |
840 | { |
841 | fprintf (stderr, "scm_gc_unregister_root called on unregistered root\n"); | |
842 | abort (); | |
843 | } | |
844 | else | |
845 | { | |
e11e83f3 | 846 | SCM count = scm_difference (SCM_CDR (handle), scm_from_int (1)); |
bc36d050 | 847 | if (scm_is_eq (count, scm_from_int (0))) |
6b1b030e ML |
848 | scm_hashv_remove_x (scm_gc_registered_roots, key); |
849 | else | |
850 | SCM_SETCDR (handle, count); | |
851 | } | |
852 | ||
853 | SCM_REALLOW_INTS; | |
854 | } | |
855 | ||
856 | void | |
857 | scm_gc_register_roots (SCM *b, unsigned long n) | |
858 | { | |
859 | SCM *p = b; | |
860 | for (; p < b + n; ++p) | |
861 | scm_gc_register_root (p); | |
862 | } | |
863 | ||
864 | void | |
865 | scm_gc_unregister_roots (SCM *b, unsigned long n) | |
866 | { | |
867 | SCM *p = b; | |
868 | for (; p < b + n; ++p) | |
869 | scm_gc_unregister_root (p); | |
870 | } | |
871 | ||
04a98cff | 872 | int scm_i_terminating; |
c45acc34 JB |
873 | |
874 | /* called on process termination. */ | |
e52ceaac MD |
875 | #ifdef HAVE_ATEXIT |
876 | static void | |
877 | cleanup (void) | |
878 | #else | |
879 | #ifdef HAVE_ON_EXIT | |
51157deb MD |
880 | extern int on_exit (void (*procp) (), int arg); |
881 | ||
e52ceaac MD |
882 | static void |
883 | cleanup (int status, void *arg) | |
884 | #else | |
885 | #error Dont know how to setup a cleanup handler on your system. | |
886 | #endif | |
887 | #endif | |
c45acc34 | 888 | { |
04a98cff | 889 | scm_i_terminating = 1; |
c45acc34 JB |
890 | scm_flush_all_ports (); |
891 | } | |
ef290276 | 892 | |
0f2d19dd | 893 | \f |
a00c95d9 | 894 | |
4c48ba06 | 895 | |
c8a1bdc4 HWN |
896 | /* |
897 | MOVE THIS FUNCTION. IT DOES NOT HAVE ANYTHING TODO WITH GC. | |
898 | */ | |
85db4a2c DH |
899 | |
900 | /* Get an integer from an environment variable. */ | |
c8a1bdc4 HWN |
901 | int |
902 | scm_getenv_int (const char *var, int def) | |
85db4a2c | 903 | { |
c8a1bdc4 HWN |
904 | char *end = 0; |
905 | char *val = getenv (var); | |
906 | long res = def; | |
85db4a2c DH |
907 | if (!val) |
908 | return def; | |
909 | res = strtol (val, &end, 10); | |
910 | if (end == val) | |
911 | return def; | |
912 | return res; | |
913 | } | |
914 | ||
c35738c1 MD |
915 | void |
916 | scm_storage_prehistory () | |
917 | { | |
918 | scm_c_hook_init (&scm_before_gc_c_hook, 0, SCM_C_HOOK_NORMAL); | |
919 | scm_c_hook_init (&scm_before_mark_c_hook, 0, SCM_C_HOOK_NORMAL); | |
920 | scm_c_hook_init (&scm_before_sweep_c_hook, 0, SCM_C_HOOK_NORMAL); | |
921 | scm_c_hook_init (&scm_after_sweep_c_hook, 0, SCM_C_HOOK_NORMAL); | |
922 | scm_c_hook_init (&scm_after_gc_c_hook, 0, SCM_C_HOOK_NORMAL); | |
923 | } | |
85db4a2c | 924 | |
76da80e7 | 925 | scm_t_mutex scm_i_gc_admin_mutex; |
eb01cb64 | 926 | |
4a4c9785 | 927 | int |
85db4a2c | 928 | scm_init_storage () |
0f2d19dd | 929 | { |
1be6b49c | 930 | size_t j; |
0f2d19dd | 931 | |
76da80e7 MV |
932 | /* Fixme: Should use mutexattr from the low-level API. */ |
933 | scm_rec_mutex_init (&scm_i_sweep_mutex, &scm_i_plugin_rec_mutex); | |
934 | ||
935 | scm_i_plugin_mutex_init (&scm_i_gc_admin_mutex, &scm_i_plugin_mutex); | |
936 | ||
0f2d19dd JB |
937 | j = SCM_NUM_PROTECTS; |
938 | while (j) | |
939 | scm_sys_protects[--j] = SCM_BOOL_F; | |
940 | scm_block_gc = 1; | |
4a4c9785 | 941 | |
c8a1bdc4 HWN |
942 | scm_gc_init_freelist(); |
943 | scm_gc_init_malloc (); | |
0f2d19dd JB |
944 | |
945 | j = SCM_HEAP_SEG_SIZE; | |
d6884e63 | 946 | |
c8a1bdc4 | 947 | |
0f2d19dd | 948 | /* Initialise the list of ports. */ |
67329a9e HWN |
949 | scm_i_port_table = (scm_t_port **) |
950 | malloc (sizeof (scm_t_port *) * scm_i_port_table_room); | |
951 | if (!scm_i_port_table) | |
0f2d19dd JB |
952 | return 1; |
953 | ||
a18bcd0e | 954 | #ifdef HAVE_ATEXIT |
c45acc34 | 955 | atexit (cleanup); |
e52ceaac MD |
956 | #else |
957 | #ifdef HAVE_ON_EXIT | |
958 | on_exit (cleanup, 0); | |
959 | #endif | |
a18bcd0e | 960 | #endif |
0f2d19dd | 961 | |
82c76fd3 | 962 | scm_stand_in_procs = scm_c_make_hash_table (257); |
0f2d19dd | 963 | scm_permobjs = SCM_EOL; |
00ffa0e7 | 964 | scm_protects = scm_c_make_hash_table (31); |
6b1b030e | 965 | scm_gc_registered_roots = scm_c_make_hash_table (31); |
d6884e63 | 966 | |
0f2d19dd JB |
967 | return 0; |
968 | } | |
939794ce | 969 | |
0f2d19dd JB |
970 | \f |
971 | ||
939794ce DH |
972 | SCM scm_after_gc_hook; |
973 | ||
939794ce DH |
974 | static SCM gc_async; |
975 | ||
939794ce DH |
976 | /* The function gc_async_thunk causes the execution of the after-gc-hook. It |
977 | * is run after the gc, as soon as the asynchronous events are handled by the | |
978 | * evaluator. | |
979 | */ | |
980 | static SCM | |
981 | gc_async_thunk (void) | |
982 | { | |
983 | scm_c_run_hook (scm_after_gc_hook, SCM_EOL); | |
939794ce DH |
984 | return SCM_UNSPECIFIED; |
985 | } | |
986 | ||
987 | ||
988 | /* The function mark_gc_async is run by the scm_after_gc_c_hook at the end of | |
989 | * the garbage collection. The only purpose of this function is to mark the | |
990 | * gc_async (which will eventually lead to the execution of the | |
991 | * gc_async_thunk). | |
992 | */ | |
993 | static void * | |
e81d98ec DH |
994 | mark_gc_async (void * hook_data SCM_UNUSED, |
995 | void *func_data SCM_UNUSED, | |
996 | void *data SCM_UNUSED) | |
997 | { | |
998 | /* If cell access debugging is enabled, the user may choose to perform | |
999 | * additional garbage collections after an arbitrary number of cell | |
1000 | * accesses. We don't want the scheme level after-gc-hook to be performed | |
1001 | * for each of these garbage collections for the following reason: The | |
1002 | * execution of the after-gc-hook causes cell accesses itself. Thus, if the | |
1003 | * after-gc-hook was performed with every gc, and if the gc was performed | |
1004 | * after a very small number of cell accesses, then the number of cell | |
1005 | * accesses during the execution of the after-gc-hook will suffice to cause | |
1006 | * the execution of the next gc. Then, guile would keep executing the | |
1007 | * after-gc-hook over and over again, and would never come to do other | |
1008 | * things. | |
eae33935 | 1009 | * |
e81d98ec DH |
1010 | * To overcome this problem, if cell access debugging with additional |
1011 | * garbage collections is enabled, the after-gc-hook is never run by the | |
1012 | * garbage collecter. When running guile with cell access debugging and the | |
1013 | * execution of the after-gc-hook is desired, then it is necessary to run | |
1014 | * the hook explicitly from the user code. This has the effect, that from | |
1015 | * the scheme level point of view it seems that garbage collection is | |
1016 | * performed with a much lower frequency than it actually is. Obviously, | |
1017 | * this will not work for code that depends on a fixed one to one | |
1018 | * relationship between the execution counts of the C level garbage | |
1019 | * collection hooks and the execution count of the scheme level | |
1020 | * after-gc-hook. | |
1021 | */ | |
1022 | #if (SCM_DEBUG_CELL_ACCESSES == 1) | |
eab1b259 | 1023 | if (scm_debug_cells_gc_interval == 0) |
e81d98ec DH |
1024 | scm_system_async_mark (gc_async); |
1025 | #else | |
939794ce | 1026 | scm_system_async_mark (gc_async); |
e81d98ec DH |
1027 | #endif |
1028 | ||
939794ce DH |
1029 | return NULL; |
1030 | } | |
1031 | ||
0f2d19dd JB |
1032 | void |
1033 | scm_init_gc () | |
0f2d19dd | 1034 | { |
c8a1bdc4 | 1035 | scm_gc_init_mark (); |
d678e25c | 1036 | |
fde50407 ML |
1037 | scm_after_gc_hook = scm_permanent_object (scm_make_hook (SCM_INUM0)); |
1038 | scm_c_define ("after-gc-hook", scm_after_gc_hook); | |
939794ce | 1039 | |
2592c4c7 MV |
1040 | gc_async = scm_c_make_subr ("%gc-thunk", scm_tc7_subr_0, |
1041 | gc_async_thunk); | |
939794ce DH |
1042 | |
1043 | scm_c_hook_add (&scm_after_gc_c_hook, mark_gc_async, NULL, 0); | |
1044 | ||
a0599745 | 1045 | #include "libguile/gc.x" |
0f2d19dd | 1046 | } |
89e00824 | 1047 | |
c8a1bdc4 HWN |
1048 | |
1049 | void | |
1050 | scm_gc_sweep (void) | |
1051 | #define FUNC_NAME "scm_gc_sweep" | |
1052 | { | |
1053 | scm_i_deprecated_memory_return = 0; | |
1054 | ||
1055 | scm_i_gc_sweep_freelist_reset (&scm_i_master_freelist); | |
1056 | scm_i_gc_sweep_freelist_reset (&scm_i_master_freelist2); | |
1057 | ||
1058 | /* | |
1059 | NOTHING HERE: LAZY SWEEPING ! | |
1060 | */ | |
1061 | scm_i_reset_segments (); | |
1062 | ||
1063 | /* When we move to POSIX threads private freelists should probably | |
1064 | be GC-protected instead. */ | |
9bc4701c MD |
1065 | *SCM_FREELIST_LOC (scm_i_freelist) = SCM_EOL; |
1066 | *SCM_FREELIST_LOC (scm_i_freelist2) = SCM_EOL; | |
392d2833 MD |
1067 | |
1068 | /* Invalidate the freelists of other threads. */ | |
1069 | scm_i_thread_invalidate_freelists (); | |
c8a1bdc4 HWN |
1070 | } |
1071 | ||
1072 | #undef FUNC_NAME | |
1073 | ||
1074 | ||
56495472 | 1075 | |
89e00824 ML |
1076 | /* |
1077 | Local Variables: | |
1078 | c-file-style: "gnu" | |
1079 | End: | |
1080 | */ |