Commit | Line | Data |
---|---|---|
c35738c1 | 1 | /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002, 2003 Free Software Foundation, Inc. |
a00c95d9 | 2 | * |
0f2d19dd JB |
3 | * This program is free software; you can redistribute it and/or modify |
4 | * it under the terms of the GNU General Public License as published by | |
5 | * the Free Software Foundation; either version 2, or (at your option) | |
6 | * any later version. | |
a00c95d9 | 7 | * |
0f2d19dd JB |
8 | * This program is distributed in the hope that it will be useful, |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
a00c95d9 | 12 | * |
0f2d19dd JB |
13 | * You should have received a copy of the GNU General Public License |
14 | * along with this software; see the file COPYING. If not, write to | |
82892bed JB |
15 | * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, |
16 | * Boston, MA 02111-1307 USA | |
0f2d19dd JB |
17 | * |
18 | * As a special exception, the Free Software Foundation gives permission | |
19 | * for additional uses of the text contained in its release of GUILE. | |
20 | * | |
21 | * The exception is that, if you link the GUILE library with other files | |
22 | * to produce an executable, this does not by itself cause the | |
23 | * resulting executable to be covered by the GNU General Public License. | |
24 | * Your use of that executable is in no way restricted on account of | |
25 | * linking the GUILE library code into it. | |
26 | * | |
27 | * This exception does not however invalidate any other reasons why | |
28 | * the executable file might be covered by the GNU General Public License. | |
29 | * | |
30 | * This exception applies only to the code released by the | |
31 | * Free Software Foundation under the name GUILE. If you copy | |
32 | * code from other Free Software Foundation releases into a copy of | |
33 | * GUILE, as the General Public License permits, the exception does | |
34 | * not apply to the code that you add in this way. To avoid misleading | |
35 | * anyone as to the status of such modified files, you must delete | |
36 | * this exception notice from them. | |
37 | * | |
38 | * If you write modifications of your own for GUILE, it is your choice | |
39 | * whether to permit this exception to apply to your modifications. | |
82892bed | 40 | * If you do not wish that, delete this exception notice. */ |
1bbd0b84 | 41 | |
1bbd0b84 | 42 | |
37ddcaf6 MD |
43 | /* #define DEBUGINFO */ |
44 | ||
aa54a9b0 RB |
45 | #if HAVE_CONFIG_H |
46 | # include <config.h> | |
47 | #endif | |
56495472 | 48 | |
0f2d19dd | 49 | #include <stdio.h> |
e6e2e95a | 50 | #include <errno.h> |
783e7774 | 51 | #include <string.h> |
c8a1bdc4 | 52 | #include <assert.h> |
e6e2e95a | 53 | |
d9189652 RB |
54 | #ifdef __ia64__ |
55 | #include <ucontext.h> | |
bb1180ef | 56 | extern unsigned long * __libc_ia64_register_backing_store_base; |
d9189652 RB |
57 | #endif |
58 | ||
a0599745 | 59 | #include "libguile/_scm.h" |
0a7a7445 | 60 | #include "libguile/eval.h" |
a0599745 MD |
61 | #include "libguile/stime.h" |
62 | #include "libguile/stackchk.h" | |
63 | #include "libguile/struct.h" | |
a0599745 MD |
64 | #include "libguile/smob.h" |
65 | #include "libguile/unif.h" | |
66 | #include "libguile/async.h" | |
67 | #include "libguile/ports.h" | |
68 | #include "libguile/root.h" | |
69 | #include "libguile/strings.h" | |
70 | #include "libguile/vectors.h" | |
801cb5e7 | 71 | #include "libguile/weaks.h" |
686765af | 72 | #include "libguile/hashtab.h" |
ecf470a2 | 73 | #include "libguile/tags.h" |
a0599745 | 74 | |
c8a1bdc4 | 75 | #include "libguile/private-gc.h" |
a0599745 | 76 | #include "libguile/validate.h" |
1be6b49c | 77 | #include "libguile/deprecation.h" |
a0599745 | 78 | #include "libguile/gc.h" |
fce59c93 | 79 | |
bc9d9bb2 | 80 | #ifdef GUILE_DEBUG_MALLOC |
a0599745 | 81 | #include "libguile/debug-malloc.h" |
bc9d9bb2 MD |
82 | #endif |
83 | ||
0f2d19dd | 84 | #ifdef HAVE_MALLOC_H |
95b88819 | 85 | #include <malloc.h> |
0f2d19dd JB |
86 | #endif |
87 | ||
88 | #ifdef HAVE_UNISTD_H | |
95b88819 | 89 | #include <unistd.h> |
0f2d19dd JB |
90 | #endif |
91 | ||
406c7d90 | 92 | |
8c494e99 | 93 | |
406c7d90 DH |
94 | unsigned int scm_gc_running_p = 0; |
95 | ||
fb50ef08 MD |
96 | /* Lock this mutex before doing lazy sweeping. |
97 | */ | |
98 | scm_t_rec_mutex scm_i_sweep_mutex; | |
99 | ||
eae33935 | 100 | /* Set this to != 0 if every cell that is accessed shall be checked: |
61045190 | 101 | */ |
eab1b259 HWN |
102 | int scm_debug_cell_accesses_p = 0; |
103 | int scm_expensive_debug_cell_accesses_p = 0; | |
406c7d90 | 104 | |
e81d98ec DH |
105 | /* Set this to 0 if no additional gc's shall be performed, otherwise set it to |
106 | * the number of cell accesses after which a gc shall be called. | |
107 | */ | |
eab1b259 | 108 | int scm_debug_cells_gc_interval = 0; |
e81d98ec | 109 | |
eab1b259 HWN |
110 | /* |
111 | Global variable, so you can switch it off at runtime by setting | |
112 | scm_i_cell_validation_already_running. | |
406c7d90 | 113 | */ |
eab1b259 HWN |
114 | int scm_i_cell_validation_already_running ; |
115 | ||
116 | #if (SCM_DEBUG_CELL_ACCESSES == 1) | |
117 | ||
118 | ||
119 | /* | |
120 | ||
121 | Assert that the given object is a valid reference to a valid cell. This | |
122 | test involves to determine whether the object is a cell pointer, whether | |
123 | this pointer actually points into a heap segment and whether the cell | |
124 | pointed to is not a free cell. Further, additional garbage collections may | |
125 | get executed after a user defined number of cell accesses. This helps to | |
126 | find places in the C code where references are dropped for extremely short | |
127 | periods. | |
128 | ||
129 | */ | |
406c7d90 | 130 | void |
eab1b259 | 131 | scm_i_expensive_validation_check (SCM cell) |
406c7d90 | 132 | { |
eab1b259 HWN |
133 | if (!scm_in_heap_p (cell)) |
134 | { | |
135 | fprintf (stderr, "scm_assert_cell_valid: this object does not live in the heap: %lux\n", | |
136 | (unsigned long) SCM_UNPACK (cell)); | |
137 | abort (); | |
138 | } | |
139 | ||
140 | /* If desired, perform additional garbage collections after a user | |
141 | * defined number of cell accesses. | |
142 | */ | |
143 | if (scm_debug_cells_gc_interval) | |
144 | { | |
145 | static unsigned int counter = 0; | |
61045190 | 146 | |
eab1b259 HWN |
147 | if (counter != 0) |
148 | { | |
149 | --counter; | |
150 | } | |
151 | else | |
152 | { | |
153 | counter = scm_debug_cells_gc_interval; | |
154 | scm_igc ("scm_assert_cell_valid"); | |
155 | } | |
156 | } | |
157 | } | |
158 | ||
159 | void | |
160 | scm_assert_cell_valid (SCM cell) | |
161 | { | |
162 | if (!scm_i_cell_validation_already_running && scm_debug_cell_accesses_p) | |
406c7d90 | 163 | { |
eab1b259 | 164 | scm_i_cell_validation_already_running = 1; /* set to avoid recursion */ |
406c7d90 | 165 | |
c8a1bdc4 | 166 | /* |
eab1b259 HWN |
167 | During GC, no user-code should be run, and the guile core |
168 | should use non-protected accessors. | |
169 | */ | |
c8a1bdc4 | 170 | if (scm_gc_running_p) |
eab1b259 | 171 | return; |
c8a1bdc4 HWN |
172 | |
173 | /* | |
eab1b259 HWN |
174 | Only scm_in_heap_p and rescanning the heap is wildly |
175 | expensive. | |
176 | */ | |
177 | if (scm_expensive_debug_cell_accesses_p) | |
178 | scm_i_expensive_validation_check (cell); | |
c8a1bdc4 HWN |
179 | |
180 | if (!SCM_GC_MARK_P (cell)) | |
406c7d90 | 181 | { |
c8a1bdc4 HWN |
182 | fprintf (stderr, |
183 | "scm_assert_cell_valid: this object is unmarked. \n" | |
184 | "It has been garbage-collected in the last GC run: " | |
185 | "%lux\n", | |
1be6b49c | 186 | (unsigned long) SCM_UNPACK (cell)); |
406c7d90 DH |
187 | abort (); |
188 | } | |
c8a1bdc4 | 189 | |
eab1b259 | 190 | scm_i_cell_validation_already_running = 0; /* re-enable */ |
406c7d90 DH |
191 | } |
192 | } | |
193 | ||
194 | ||
eab1b259 | 195 | |
406c7d90 DH |
196 | SCM_DEFINE (scm_set_debug_cell_accesses_x, "set-debug-cell-accesses!", 1, 0, 0, |
197 | (SCM flag), | |
1e6808ea | 198 | "If @var{flag} is @code{#f}, cell access checking is disabled.\n" |
eab1b259 | 199 | "If @var{flag} is @code{#t}, cheap cell access checking is enabled,\n" |
e81d98ec | 200 | "but no additional calls to garbage collection are issued.\n" |
eab1b259 | 201 | "If @var{flag} is a number, strict cell access checking is enabled,\n" |
e81d98ec DH |
202 | "with an additional garbage collection after the given\n" |
203 | "number of cell accesses.\n" | |
1e6808ea MG |
204 | "This procedure only exists when the compile-time flag\n" |
205 | "@code{SCM_DEBUG_CELL_ACCESSES} was set to 1.") | |
406c7d90 DH |
206 | #define FUNC_NAME s_scm_set_debug_cell_accesses_x |
207 | { | |
eab1b259 HWN |
208 | if (SCM_FALSEP (flag)) |
209 | { | |
210 | scm_debug_cell_accesses_p = 0; | |
211 | } | |
212 | else if (SCM_EQ_P (flag, SCM_BOOL_T)) | |
213 | { | |
214 | scm_debug_cells_gc_interval = 0; | |
215 | scm_debug_cell_accesses_p = 1; | |
216 | scm_expensive_debug_cell_accesses_p = 0; | |
217 | } | |
218 | else if (SCM_INUMP (flag)) | |
219 | { | |
220 | long int f = SCM_INUM (flag); | |
221 | if (f <= 0) | |
222 | SCM_OUT_OF_RANGE (1, flag); | |
223 | scm_debug_cells_gc_interval = f; | |
224 | scm_debug_cell_accesses_p = 1; | |
225 | scm_expensive_debug_cell_accesses_p = 1; | |
226 | } | |
227 | else | |
228 | { | |
229 | SCM_WRONG_TYPE_ARG (1, flag); | |
230 | } | |
406c7d90 DH |
231 | return SCM_UNSPECIFIED; |
232 | } | |
233 | #undef FUNC_NAME | |
c8a1bdc4 | 234 | #else |
0f2d19dd | 235 | |
8fef55a8 | 236 | /* |
c8a1bdc4 HWN |
237 | Provide a stub, so people can use their Scheme code on non-debug |
238 | versions of GUILE as well. | |
4c48ba06 | 239 | */ |
c8a1bdc4 HWN |
240 | SCM_DEFINE (scm_set_debug_cell_accesses_x, "set-debug-cell-accesses!", 1, 0, 0, |
241 | (SCM flag), | |
242 | "This function is used to turn on checking for a debug version of GUILE. This version does not support this functionality\n") | |
243 | #define FUNC_NAME s_scm_set_debug_cell_accesses_x | |
244 | { | |
245 | ||
246 | /* | |
247 | do nothing | |
248 | */ | |
1e71eafb | 249 | fprintf (stderr, "\nWARNING: GUILE was not compiled with SCM_DEBUG_CELL_ACCESSES"); |
c8a1bdc4 HWN |
250 | scm_remember_upto_here (flag); |
251 | return SCM_UNSPECIFIED; | |
252 | } | |
253 | #undef FUNC_NAME | |
ecf470a2 | 254 | |
c8a1bdc4 | 255 | #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */ |
0f2d19dd JB |
256 | |
257 | \f | |
945fec60 | 258 | |
9bc4701c MD |
259 | scm_t_key scm_i_freelist; |
260 | scm_t_key scm_i_freelist2; | |
c8a1bdc4 | 261 | |
0f2d19dd JB |
262 | |
263 | /* scm_mtrigger | |
539b08a4 | 264 | * is the number of bytes of malloc allocation needed to trigger gc. |
0f2d19dd | 265 | */ |
c014a02e | 266 | unsigned long scm_mtrigger; |
0f2d19dd | 267 | |
0f2d19dd JB |
268 | /* scm_gc_heap_lock |
269 | * If set, don't expand the heap. Set only during gc, during which no allocation | |
270 | * is supposed to take place anyway. | |
271 | */ | |
272 | int scm_gc_heap_lock = 0; | |
273 | ||
274 | /* GC Blocking | |
275 | * Don't pause for collection if this is set -- just | |
276 | * expand the heap. | |
277 | */ | |
0f2d19dd JB |
278 | int scm_block_gc = 1; |
279 | ||
0f2d19dd JB |
280 | /* During collection, this accumulates objects holding |
281 | * weak references. | |
282 | */ | |
ab4bef85 | 283 | SCM scm_weak_vectors; |
0f2d19dd JB |
284 | |
285 | /* GC Statistics Keeping | |
286 | */ | |
f2893a25 | 287 | unsigned long scm_cells_allocated = 0; |
c014a02e ML |
288 | unsigned long scm_mallocated = 0; |
289 | unsigned long scm_gc_cells_collected; | |
c8a1bdc4 | 290 | unsigned long scm_gc_cells_collected_1 = 0; /* previous GC yield */ |
c014a02e ML |
291 | unsigned long scm_gc_malloc_collected; |
292 | unsigned long scm_gc_ports_collected; | |
0f2d19dd | 293 | unsigned long scm_gc_time_taken = 0; |
c014a02e | 294 | static unsigned long t_before_gc; |
c9b0d4b0 | 295 | unsigned long scm_gc_mark_time_taken = 0; |
c014a02e ML |
296 | unsigned long scm_gc_times = 0; |
297 | unsigned long scm_gc_cells_swept = 0; | |
c9b0d4b0 ML |
298 | double scm_gc_cells_marked_acc = 0.; |
299 | double scm_gc_cells_swept_acc = 0.; | |
c2cbcc57 HWN |
300 | int scm_gc_cell_yield_percentage =0; |
301 | int scm_gc_malloc_yield_percentage = 0; | |
302 | ||
0f2d19dd JB |
303 | |
304 | SCM_SYMBOL (sym_cells_allocated, "cells-allocated"); | |
305 | SCM_SYMBOL (sym_heap_size, "cell-heap-size"); | |
306 | SCM_SYMBOL (sym_mallocated, "bytes-malloced"); | |
307 | SCM_SYMBOL (sym_mtrigger, "gc-malloc-threshold"); | |
308 | SCM_SYMBOL (sym_heap_segments, "cell-heap-segments"); | |
309 | SCM_SYMBOL (sym_gc_time_taken, "gc-time-taken"); | |
c9b0d4b0 | 310 | SCM_SYMBOL (sym_gc_mark_time_taken, "gc-mark-time-taken"); |
c9b0d4b0 ML |
311 | SCM_SYMBOL (sym_times, "gc-times"); |
312 | SCM_SYMBOL (sym_cells_marked, "cells-marked"); | |
313 | SCM_SYMBOL (sym_cells_swept, "cells-swept"); | |
c2cbcc57 HWN |
314 | SCM_SYMBOL (sym_malloc_yield, "malloc-yield"); |
315 | SCM_SYMBOL (sym_cell_yield, "cell-yield"); | |
0f2d19dd | 316 | |
bb2c57fa | 317 | |
cf2d30f6 | 318 | |
d3dd80ab | 319 | |
cf2d30f6 | 320 | /* Number of calls to SCM_NEWCELL since startup. */ |
c8a1bdc4 HWN |
321 | unsigned scm_newcell_count; |
322 | unsigned scm_newcell2_count; | |
b37fe1c5 | 323 | |
b37fe1c5 | 324 | |
0f2d19dd JB |
325 | /* {Scheme Interface to GC} |
326 | */ | |
c2cbcc57 | 327 | extern int scm_gc_malloc_yield_percentage; |
a00c95d9 | 328 | SCM_DEFINE (scm_gc_stats, "gc-stats", 0, 0, 0, |
1bbd0b84 | 329 | (), |
1e6808ea | 330 | "Return an association list of statistics about Guile's current\n" |
c8a1bdc4 | 331 | "use of storage.\n") |
1bbd0b84 | 332 | #define FUNC_NAME s_scm_gc_stats |
0f2d19dd | 333 | { |
c8a1bdc4 HWN |
334 | long i = 0; |
335 | SCM heap_segs = SCM_EOL ; | |
c014a02e ML |
336 | unsigned long int local_scm_mtrigger; |
337 | unsigned long int local_scm_mallocated; | |
338 | unsigned long int local_scm_heap_size; | |
c2cbcc57 HWN |
339 | int local_scm_gc_cell_yield_percentage; |
340 | int local_scm_gc_malloc_yield_percentage; | |
f2893a25 | 341 | unsigned long int local_scm_cells_allocated; |
c014a02e ML |
342 | unsigned long int local_scm_gc_time_taken; |
343 | unsigned long int local_scm_gc_times; | |
344 | unsigned long int local_scm_gc_mark_time_taken; | |
c9b0d4b0 ML |
345 | double local_scm_gc_cells_swept; |
346 | double local_scm_gc_cells_marked; | |
0f2d19dd | 347 | SCM answer; |
c8a1bdc4 HWN |
348 | unsigned long *bounds = 0; |
349 | int table_size = scm_i_heap_segment_table_size; | |
0f2d19dd | 350 | SCM_DEFER_INTS; |
939794ce | 351 | |
c8a1bdc4 HWN |
352 | /* |
353 | temporarily store the numbers, so as not to cause GC. | |
7febb4a2 | 354 | */ |
c8a1bdc4 HWN |
355 | |
356 | bounds = malloc (sizeof (int) * table_size * 2); | |
357 | if (!bounds) | |
358 | abort(); | |
359 | for (i = table_size; i--; ) | |
360 | { | |
361 | bounds[2*i] = (unsigned long)scm_i_heap_segment_table[i]->bounds[0]; | |
362 | bounds[2*i+1] = (unsigned long)scm_i_heap_segment_table[i]->bounds[1]; | |
363 | } | |
0f2d19dd | 364 | |
4c9419ac | 365 | |
c8a1bdc4 HWN |
366 | /* Below, we cons to produce the resulting list. We want a snapshot of |
367 | * the heap situation before consing. | |
368 | */ | |
369 | local_scm_mtrigger = scm_mtrigger; | |
370 | local_scm_mallocated = scm_mallocated; | |
371 | local_scm_heap_size = SCM_HEAP_SIZE; | |
539b08a4 | 372 | |
c8a1bdc4 HWN |
373 | local_scm_cells_allocated = scm_cells_allocated; |
374 | ||
375 | local_scm_gc_time_taken = scm_gc_time_taken; | |
376 | local_scm_gc_mark_time_taken = scm_gc_mark_time_taken; | |
377 | local_scm_gc_times = scm_gc_times; | |
c2cbcc57 HWN |
378 | local_scm_gc_malloc_yield_percentage = scm_gc_malloc_yield_percentage; |
379 | local_scm_gc_cell_yield_percentage= scm_gc_cell_yield_percentage; | |
380 | ||
381 | local_scm_gc_cells_swept = | |
382 | (double) scm_gc_cells_swept_acc | |
383 | + (double) scm_gc_cells_swept; | |
c8a1bdc4 HWN |
384 | local_scm_gc_cells_marked = scm_gc_cells_marked_acc |
385 | +(double) scm_gc_cells_swept | |
386 | -(double) scm_gc_cells_collected; | |
0f2d19dd | 387 | |
c8a1bdc4 HWN |
388 | for (i = table_size; i--;) |
389 | { | |
390 | heap_segs = scm_cons (scm_cons (scm_ulong2num (bounds[2*i]), | |
391 | scm_ulong2num (bounds[2*i+1])), | |
392 | heap_segs); | |
393 | } | |
394 | ||
395 | answer = scm_list_n (scm_cons (sym_gc_time_taken, scm_ulong2num (local_scm_gc_time_taken)), | |
f2893a25 | 396 | scm_cons (sym_cells_allocated, scm_ulong2num (local_scm_cells_allocated)), |
c8a1bdc4 HWN |
397 | scm_cons (sym_heap_size, scm_ulong2num (local_scm_heap_size)), |
398 | scm_cons (sym_mallocated, scm_ulong2num (local_scm_mallocated)), | |
399 | scm_cons (sym_mtrigger, scm_ulong2num (local_scm_mtrigger)), | |
400 | scm_cons (sym_times, scm_ulong2num (local_scm_gc_times)), | |
401 | scm_cons (sym_gc_mark_time_taken, scm_ulong2num (local_scm_gc_mark_time_taken)), | |
402 | scm_cons (sym_cells_marked, scm_i_dbl2big (local_scm_gc_cells_marked)), | |
403 | scm_cons (sym_cells_swept, scm_i_dbl2big (local_scm_gc_cells_swept)), | |
c2cbcc57 HWN |
404 | scm_cons (sym_malloc_yield, scm_long2num (local_scm_gc_malloc_yield_percentage)), |
405 | scm_cons (sym_cell_yield, scm_long2num (local_scm_gc_cell_yield_percentage)), | |
c8a1bdc4 HWN |
406 | scm_cons (sym_heap_segments, heap_segs), |
407 | SCM_UNDEFINED); | |
408 | SCM_ALLOW_INTS; | |
409 | ||
410 | free (bounds); | |
411 | return answer; | |
0f2d19dd | 412 | } |
c8a1bdc4 | 413 | #undef FUNC_NAME |
0f2d19dd | 414 | |
c8a1bdc4 HWN |
415 | static void |
416 | gc_start_stats (const char *what SCM_UNUSED) | |
e4a7824f | 417 | { |
c8a1bdc4 | 418 | t_before_gc = scm_c_get_internal_run_time (); |
539b08a4 | 419 | |
c8a1bdc4 HWN |
420 | scm_gc_cells_marked_acc += (double) scm_gc_cells_swept |
421 | - (double) scm_gc_cells_collected; | |
c2cbcc57 | 422 | scm_gc_cells_swept_acc += (double) scm_gc_cells_swept; |
e4a7824f | 423 | |
c2cbcc57 HWN |
424 | scm_gc_cell_yield_percentage = ( scm_gc_cells_collected * 100 ) / SCM_HEAP_SIZE; |
425 | ||
c8a1bdc4 HWN |
426 | scm_gc_cells_swept = 0; |
427 | scm_gc_cells_collected_1 = scm_gc_cells_collected; | |
539b08a4 | 428 | |
c8a1bdc4 HWN |
429 | /* |
430 | CELLS SWEPT is another word for the number of cells that were | |
431 | examined during GC. YIELD is the number that we cleaned | |
432 | out. MARKED is the number that weren't cleaned. | |
433 | */ | |
434 | scm_gc_cells_collected = 0; | |
435 | scm_gc_malloc_collected = 0; | |
436 | scm_gc_ports_collected = 0; | |
e4a7824f | 437 | } |
acf4331f | 438 | |
c8a1bdc4 HWN |
439 | static void |
440 | gc_end_stats () | |
0f2d19dd | 441 | { |
c8a1bdc4 HWN |
442 | unsigned long t = scm_c_get_internal_run_time (); |
443 | scm_gc_time_taken += (t - t_before_gc); | |
539b08a4 | 444 | |
c8a1bdc4 | 445 | ++scm_gc_times; |
0f2d19dd | 446 | } |
acf4331f | 447 | |
0f2d19dd | 448 | |
c8a1bdc4 HWN |
449 | SCM_DEFINE (scm_object_address, "object-address", 1, 0, 0, |
450 | (SCM obj), | |
451 | "Return an integer that for the lifetime of @var{obj} is uniquely\n" | |
452 | "returned by this function for @var{obj}") | |
453 | #define FUNC_NAME s_scm_object_address | |
c68296f8 | 454 | { |
c8a1bdc4 | 455 | return scm_ulong2num ((unsigned long) SCM_UNPACK (obj)); |
c68296f8 | 456 | } |
c8a1bdc4 | 457 | #undef FUNC_NAME |
c68296f8 | 458 | |
1be6b49c | 459 | |
c8a1bdc4 HWN |
460 | SCM_DEFINE (scm_gc, "gc", 0, 0, 0, |
461 | (), | |
462 | "Scans all of SCM objects and reclaims for further use those that are\n" | |
463 | "no longer accessible.") | |
464 | #define FUNC_NAME s_scm_gc | |
465 | { | |
c8a1bdc4 | 466 | scm_igc ("call"); |
c8a1bdc4 | 467 | return SCM_UNSPECIFIED; |
9d47a1e6 | 468 | } |
c8a1bdc4 | 469 | #undef FUNC_NAME |
9d47a1e6 | 470 | |
c68296f8 MV |
471 | |
472 | \f | |
0f2d19dd | 473 | |
c8a1bdc4 HWN |
474 | /* When we get POSIX threads support, the master will be global and |
475 | * common while the freelist will be individual for each thread. | |
0f2d19dd JB |
476 | */ |
477 | ||
c8a1bdc4 HWN |
478 | SCM |
479 | scm_gc_for_newcell (scm_t_cell_type_statistics *freelist, SCM *free_cells) | |
0f2d19dd | 480 | { |
c8a1bdc4 HWN |
481 | SCM cell; |
482 | ||
fb50ef08 | 483 | scm_rec_mutex_lock (&scm_i_sweep_mutex); |
9bc4701c | 484 | |
c8a1bdc4 HWN |
485 | *free_cells = scm_i_sweep_some_segments (freelist); |
486 | if (*free_cells == SCM_EOL && scm_i_gc_grow_heap_p (freelist)) | |
487 | { | |
488 | freelist->heap_segment_idx = scm_i_get_new_heap_segment (freelist, abort_on_error); | |
489 | *free_cells = scm_i_sweep_some_segments (freelist); | |
490 | } | |
acb0a19c | 491 | |
c8a1bdc4 HWN |
492 | if (*free_cells == SCM_EOL && !scm_block_gc) |
493 | { | |
494 | /* | |
495 | with the advent of lazy sweep, GC yield is only know just | |
496 | before doing the GC. | |
497 | */ | |
498 | scm_i_adjust_min_yield (freelist); | |
499 | ||
500 | /* | |
501 | out of fresh cells. Try to get some new ones. | |
502 | */ | |
0f2d19dd | 503 | |
c8a1bdc4 | 504 | scm_igc ("cells"); |
a00c95d9 | 505 | |
c8a1bdc4 HWN |
506 | *free_cells = scm_i_sweep_some_segments (freelist); |
507 | } | |
508 | ||
509 | if (*free_cells == SCM_EOL) | |
510 | { | |
511 | /* | |
512 | failed getting new cells. Get new juice or die. | |
513 | */ | |
514 | freelist->heap_segment_idx = scm_i_get_new_heap_segment (freelist, abort_on_error); | |
515 | *free_cells = scm_i_sweep_some_segments (freelist); | |
516 | } | |
517 | ||
518 | if (*free_cells == SCM_EOL) | |
519 | abort (); | |
0f2d19dd | 520 | |
c8a1bdc4 | 521 | cell = *free_cells; |
0f2d19dd | 522 | |
c8a1bdc4 | 523 | *free_cells = SCM_FREE_CELL_CDR (cell); |
eab1b259 | 524 | |
fb50ef08 | 525 | scm_rec_mutex_unlock (&scm_i_sweep_mutex); |
eab1b259 | 526 | |
c8a1bdc4 HWN |
527 | return cell; |
528 | } | |
4a4c9785 | 529 | |
4a4c9785 | 530 | |
c8a1bdc4 HWN |
531 | scm_t_c_hook scm_before_gc_c_hook; |
532 | scm_t_c_hook scm_before_mark_c_hook; | |
533 | scm_t_c_hook scm_before_sweep_c_hook; | |
534 | scm_t_c_hook scm_after_sweep_c_hook; | |
535 | scm_t_c_hook scm_after_gc_c_hook; | |
4a4c9785 | 536 | |
c8a1bdc4 HWN |
537 | void |
538 | scm_igc (const char *what) | |
539 | { | |
fb50ef08 | 540 | scm_rec_mutex_lock (&scm_i_sweep_mutex); |
c8a1bdc4 HWN |
541 | ++scm_gc_running_p; |
542 | scm_c_hook_run (&scm_before_gc_c_hook, 0); | |
a00c95d9 | 543 | |
c8a1bdc4 HWN |
544 | #ifdef DEBUGINFO |
545 | fprintf (stderr,"gc reason %s\n", what); | |
546 | ||
547 | fprintf (stderr, | |
9bc4701c | 548 | SCM_NULLP (*SCM_FREELIST_LOC (scm_i_freelist)) |
c8a1bdc4 | 549 | ? "*" |
9bc4701c | 550 | : (SCM_NULLP (*SCM_FREELIST_LOC (scm_i_freelist2)) ? "o" : "m")); |
c8a1bdc4 | 551 | #endif |
4c48ba06 | 552 | |
c8a1bdc4 | 553 | /* During the critical section, only the current thread may run. */ |
fb50ef08 | 554 | scm_i_thread_put_to_sleep (); |
a00c95d9 | 555 | |
eab1b259 | 556 | if (!scm_root || !scm_stack_base || scm_block_gc) |
d6884e63 | 557 | { |
c8a1bdc4 HWN |
558 | --scm_gc_running_p; |
559 | return; | |
d6884e63 ML |
560 | } |
561 | ||
c8a1bdc4 | 562 | gc_start_stats (what); |
a00c95d9 | 563 | |
c8a1bdc4 HWN |
564 | if (scm_gc_heap_lock) |
565 | /* We've invoked the collector while a GC is already in progress. | |
566 | That should never happen. */ | |
567 | abort (); | |
a00c95d9 | 568 | |
c8a1bdc4 | 569 | ++scm_gc_heap_lock; |
a00c95d9 | 570 | |
c8a1bdc4 HWN |
571 | /* |
572 | Let's finish the sweep. The conservative GC might point into the | |
573 | garbage, and marking that would create a mess. | |
574 | */ | |
575 | scm_i_sweep_all_segments("GC"); | |
576 | if (scm_mallocated < scm_i_deprecated_memory_return) | |
b6efc951 | 577 | { |
c8a1bdc4 HWN |
578 | /* The byte count of allocated objects has underflowed. This is |
579 | probably because you forgot to report the sizes of objects you | |
580 | have allocated, by calling scm_done_malloc or some such. When | |
581 | the GC freed them, it subtracted their size from | |
582 | scm_mallocated, which underflowed. */ | |
583 | fprintf (stderr, | |
584 | "scm_gc_sweep: Byte count of allocated objects has underflowed.\n" | |
585 | "This is probably because the GC hasn't been correctly informed\n" | |
586 | "about object sizes\n"); | |
b6efc951 DH |
587 | abort (); |
588 | } | |
c8a1bdc4 | 589 | scm_mallocated -= scm_i_deprecated_memory_return; |
0f2d19dd | 590 | |
c8a1bdc4 HWN |
591 | |
592 | ||
593 | scm_c_hook_run (&scm_before_mark_c_hook, 0); | |
b6efc951 | 594 | |
c8a1bdc4 HWN |
595 | scm_mark_all (); |
596 | ||
c2cbcc57 | 597 | scm_gc_mark_time_taken += (scm_c_get_internal_run_time () - t_before_gc); |
c8a1bdc4 HWN |
598 | |
599 | scm_c_hook_run (&scm_before_sweep_c_hook, 0); | |
600 | ||
601 | /* | |
602 | Moved this lock upwards so that we can alloc new heap at the end of a sweep. | |
0f2d19dd | 603 | |
c8a1bdc4 | 604 | DOCME: why should the heap be locked anyway? |
0f2d19dd | 605 | */ |
c8a1bdc4 | 606 | --scm_gc_heap_lock; |
a00c95d9 | 607 | |
c8a1bdc4 | 608 | scm_gc_sweep (); |
0f2d19dd | 609 | |
ffd72400 HWN |
610 | |
611 | /* | |
612 | TODO: this hook should probably be moved to just before the mark, | |
613 | since that's where the sweep is finished in lazy sweeping. | |
c35738c1 MD |
614 | |
615 | MDJ 030219 <djurfeldt@nada.kth.se>: No, probably not. The | |
616 | original meaning implied at least two things: that it would be | |
617 | called when | |
618 | ||
619 | 1. the freelist is re-initialized (no evaluation possible, though) | |
620 | ||
621 | and | |
622 | ||
623 | 2. the heap is "fresh" | |
624 | (it is well-defined what data is used and what is not) | |
625 | ||
626 | Neither of these conditions would hold just before the mark phase. | |
627 | ||
628 | Of course, the lazy sweeping has muddled the distinction between | |
629 | scm_before_sweep_c_hook and scm_after_sweep_c_hook, but even if | |
630 | there were no difference, it would still be useful to have two | |
631 | distinct classes of hook functions since this can prevent some | |
632 | bad interference when several modules adds gc hooks. | |
ffd72400 | 633 | */ |
c8a1bdc4 HWN |
634 | scm_c_hook_run (&scm_after_sweep_c_hook, 0); |
635 | gc_end_stats (); | |
636 | ||
fb50ef08 | 637 | scm_i_thread_wake_up (); |
ffd72400 HWN |
638 | |
639 | /* | |
640 | See above. | |
641 | */ | |
c8a1bdc4 HWN |
642 | scm_c_hook_run (&scm_after_gc_c_hook, 0); |
643 | --scm_gc_running_p; | |
fb50ef08 | 644 | scm_rec_mutex_unlock (&scm_i_sweep_mutex); |
a00c95d9 | 645 | |
eab1b259 HWN |
646 | /* |
647 | For debugging purposes, you could do | |
648 | scm_i_sweep_all_segments("debug"), but then the remains of the | |
649 | cell aren't left to analyse. | |
650 | */ | |
651 | } | |
0f2d19dd | 652 | |
0f2d19dd JB |
653 | \f |
654 | /* {GC Protection Helper Functions} | |
655 | */ | |
656 | ||
657 | ||
5d2b97cd DH |
658 | /* |
659 | * If within a function you need to protect one or more scheme objects from | |
660 | * garbage collection, pass them as parameters to one of the | |
661 | * scm_remember_upto_here* functions below. These functions don't do | |
662 | * anything, but since the compiler does not know that they are actually | |
663 | * no-ops, it will generate code that calls these functions with the given | |
664 | * parameters. Therefore, you can be sure that the compiler will keep those | |
665 | * scheme values alive (on the stack or in a register) up to the point where | |
666 | * scm_remember_upto_here* is called. In other words, place the call to | |
592996c9 | 667 | * scm_remember_upto_here* _behind_ the last code in your function, that |
5d2b97cd DH |
668 | * depends on the scheme object to exist. |
669 | * | |
8c494e99 DH |
670 | * Example: We want to make sure that the string object str does not get |
671 | * garbage collected during the execution of 'some_function' in the code | |
672 | * below, because otherwise the characters belonging to str would be freed and | |
5d2b97cd DH |
673 | * 'some_function' might access freed memory. To make sure that the compiler |
674 | * keeps str alive on the stack or in a register such that it is visible to | |
675 | * the conservative gc we add the call to scm_remember_upto_here_1 _after_ the | |
676 | * call to 'some_function'. Note that this would not be necessary if str was | |
677 | * used anyway after the call to 'some_function'. | |
678 | * char *chars = SCM_STRING_CHARS (str); | |
679 | * some_function (chars); | |
680 | * scm_remember_upto_here_1 (str); // str will be alive up to this point. | |
681 | */ | |
682 | ||
683 | void | |
e81d98ec | 684 | scm_remember_upto_here_1 (SCM obj SCM_UNUSED) |
5d2b97cd DH |
685 | { |
686 | /* Empty. Protects a single object from garbage collection. */ | |
687 | } | |
688 | ||
689 | void | |
e81d98ec | 690 | scm_remember_upto_here_2 (SCM obj1 SCM_UNUSED, SCM obj2 SCM_UNUSED) |
5d2b97cd DH |
691 | { |
692 | /* Empty. Protects two objects from garbage collection. */ | |
693 | } | |
694 | ||
695 | void | |
e81d98ec | 696 | scm_remember_upto_here (SCM obj SCM_UNUSED, ...) |
5d2b97cd DH |
697 | { |
698 | /* Empty. Protects any number of objects from garbage collection. */ | |
699 | } | |
700 | ||
c209c88e | 701 | /* |
41b0806d GB |
702 | These crazy functions prevent garbage collection |
703 | of arguments after the first argument by | |
704 | ensuring they remain live throughout the | |
705 | function because they are used in the last | |
706 | line of the code block. | |
707 | It'd be better to have a nice compiler hint to | |
708 | aid the conservative stack-scanning GC. --03/09/00 gjb */ | |
0f2d19dd JB |
709 | SCM |
710 | scm_return_first (SCM elt, ...) | |
0f2d19dd JB |
711 | { |
712 | return elt; | |
713 | } | |
714 | ||
41b0806d GB |
715 | int |
716 | scm_return_first_int (int i, ...) | |
717 | { | |
718 | return i; | |
719 | } | |
720 | ||
0f2d19dd | 721 | |
0f2d19dd | 722 | SCM |
6e8d25a6 | 723 | scm_permanent_object (SCM obj) |
0f2d19dd JB |
724 | { |
725 | SCM_REDEFER_INTS; | |
726 | scm_permobjs = scm_cons (obj, scm_permobjs); | |
727 | SCM_REALLOW_INTS; | |
728 | return obj; | |
729 | } | |
730 | ||
731 | ||
7bd4fbe2 MD |
732 | /* Protect OBJ from the garbage collector. OBJ will not be freed, even if all |
733 | other references are dropped, until the object is unprotected by calling | |
6b1b030e | 734 | scm_gc_unprotect_object (OBJ). Calls to scm_gc_protect/unprotect_object nest, |
7bd4fbe2 MD |
735 | i. e. it is possible to protect the same object several times, but it is |
736 | necessary to unprotect the object the same number of times to actually get | |
737 | the object unprotected. It is an error to unprotect an object more often | |
738 | than it has been protected before. The function scm_protect_object returns | |
739 | OBJ. | |
740 | */ | |
741 | ||
742 | /* Implementation note: For every object X, there is a counter which | |
6b1b030e | 743 | scm_gc_protect_object(X) increments and scm_gc_unprotect_object(X) decrements. |
7bd4fbe2 | 744 | */ |
686765af | 745 | |
ef290276 | 746 | SCM |
6b1b030e | 747 | scm_gc_protect_object (SCM obj) |
ef290276 | 748 | { |
686765af | 749 | SCM handle; |
9d47a1e6 | 750 | |
686765af | 751 | /* This critical section barrier will be replaced by a mutex. */ |
2dd6a83a | 752 | SCM_REDEFER_INTS; |
9d47a1e6 | 753 | |
0f0f0899 | 754 | handle = scm_hashq_create_handle_x (scm_protects, obj, SCM_MAKINUM (0)); |
1be6b49c | 755 | SCM_SETCDR (handle, scm_sum (SCM_CDR (handle), SCM_MAKINUM (1))); |
9d47a1e6 | 756 | |
2dd6a83a | 757 | SCM_REALLOW_INTS; |
9d47a1e6 | 758 | |
ef290276 JB |
759 | return obj; |
760 | } | |
761 | ||
762 | ||
763 | /* Remove any protection for OBJ established by a prior call to | |
dab7f566 | 764 | scm_protect_object. This function returns OBJ. |
ef290276 | 765 | |
dab7f566 | 766 | See scm_protect_object for more information. */ |
ef290276 | 767 | SCM |
6b1b030e | 768 | scm_gc_unprotect_object (SCM obj) |
ef290276 | 769 | { |
686765af | 770 | SCM handle; |
9d47a1e6 | 771 | |
686765af | 772 | /* This critical section barrier will be replaced by a mutex. */ |
2dd6a83a | 773 | SCM_REDEFER_INTS; |
9d47a1e6 | 774 | |
686765af | 775 | handle = scm_hashq_get_handle (scm_protects, obj); |
9d47a1e6 | 776 | |
22a52da1 | 777 | if (SCM_FALSEP (handle)) |
686765af | 778 | { |
0f0f0899 MD |
779 | fprintf (stderr, "scm_unprotect_object called on unprotected object\n"); |
780 | abort (); | |
686765af | 781 | } |
6a199940 DH |
782 | else |
783 | { | |
1be6b49c ML |
784 | SCM count = scm_difference (SCM_CDR (handle), SCM_MAKINUM (1)); |
785 | if (SCM_EQ_P (count, SCM_MAKINUM (0))) | |
6a199940 DH |
786 | scm_hashq_remove_x (scm_protects, obj); |
787 | else | |
1be6b49c | 788 | SCM_SETCDR (handle, count); |
6a199940 | 789 | } |
686765af | 790 | |
2dd6a83a | 791 | SCM_REALLOW_INTS; |
ef290276 JB |
792 | |
793 | return obj; | |
794 | } | |
795 | ||
6b1b030e ML |
796 | void |
797 | scm_gc_register_root (SCM *p) | |
798 | { | |
799 | SCM handle; | |
800 | SCM key = scm_long2num ((long) p); | |
eae33935 | 801 | |
6b1b030e ML |
802 | /* This critical section barrier will be replaced by a mutex. */ |
803 | SCM_REDEFER_INTS; | |
804 | ||
805 | handle = scm_hashv_create_handle_x (scm_gc_registered_roots, key, SCM_MAKINUM (0)); | |
806 | SCM_SETCDR (handle, scm_sum (SCM_CDR (handle), SCM_MAKINUM (1))); | |
807 | ||
808 | SCM_REALLOW_INTS; | |
809 | } | |
810 | ||
811 | void | |
812 | scm_gc_unregister_root (SCM *p) | |
813 | { | |
814 | SCM handle; | |
815 | SCM key = scm_long2num ((long) p); | |
816 | ||
817 | /* This critical section barrier will be replaced by a mutex. */ | |
818 | SCM_REDEFER_INTS; | |
819 | ||
820 | handle = scm_hashv_get_handle (scm_gc_registered_roots, key); | |
821 | ||
822 | if (SCM_FALSEP (handle)) | |
823 | { | |
824 | fprintf (stderr, "scm_gc_unregister_root called on unregistered root\n"); | |
825 | abort (); | |
826 | } | |
827 | else | |
828 | { | |
829 | SCM count = scm_difference (SCM_CDR (handle), SCM_MAKINUM (1)); | |
830 | if (SCM_EQ_P (count, SCM_MAKINUM (0))) | |
831 | scm_hashv_remove_x (scm_gc_registered_roots, key); | |
832 | else | |
833 | SCM_SETCDR (handle, count); | |
834 | } | |
835 | ||
836 | SCM_REALLOW_INTS; | |
837 | } | |
838 | ||
839 | void | |
840 | scm_gc_register_roots (SCM *b, unsigned long n) | |
841 | { | |
842 | SCM *p = b; | |
843 | for (; p < b + n; ++p) | |
844 | scm_gc_register_root (p); | |
845 | } | |
846 | ||
847 | void | |
848 | scm_gc_unregister_roots (SCM *b, unsigned long n) | |
849 | { | |
850 | SCM *p = b; | |
851 | for (; p < b + n; ++p) | |
852 | scm_gc_unregister_root (p); | |
853 | } | |
854 | ||
04a98cff | 855 | int scm_i_terminating; |
c45acc34 JB |
856 | |
857 | /* called on process termination. */ | |
e52ceaac MD |
858 | #ifdef HAVE_ATEXIT |
859 | static void | |
860 | cleanup (void) | |
861 | #else | |
862 | #ifdef HAVE_ON_EXIT | |
51157deb MD |
863 | extern int on_exit (void (*procp) (), int arg); |
864 | ||
e52ceaac MD |
865 | static void |
866 | cleanup (int status, void *arg) | |
867 | #else | |
868 | #error Dont know how to setup a cleanup handler on your system. | |
869 | #endif | |
870 | #endif | |
c45acc34 | 871 | { |
04a98cff | 872 | scm_i_terminating = 1; |
c45acc34 JB |
873 | scm_flush_all_ports (); |
874 | } | |
ef290276 | 875 | |
0f2d19dd | 876 | \f |
a00c95d9 | 877 | |
4c48ba06 | 878 | |
c8a1bdc4 HWN |
879 | /* |
880 | MOVE THIS FUNCTION. IT DOES NOT HAVE ANYTHING TODO WITH GC. | |
881 | */ | |
85db4a2c DH |
882 | |
883 | /* Get an integer from an environment variable. */ | |
c8a1bdc4 HWN |
884 | int |
885 | scm_getenv_int (const char *var, int def) | |
85db4a2c | 886 | { |
c8a1bdc4 HWN |
887 | char *end = 0; |
888 | char *val = getenv (var); | |
889 | long res = def; | |
85db4a2c DH |
890 | if (!val) |
891 | return def; | |
892 | res = strtol (val, &end, 10); | |
893 | if (end == val) | |
894 | return def; | |
895 | return res; | |
896 | } | |
897 | ||
c35738c1 MD |
898 | void |
899 | scm_storage_prehistory () | |
900 | { | |
901 | scm_c_hook_init (&scm_before_gc_c_hook, 0, SCM_C_HOOK_NORMAL); | |
902 | scm_c_hook_init (&scm_before_mark_c_hook, 0, SCM_C_HOOK_NORMAL); | |
903 | scm_c_hook_init (&scm_before_sweep_c_hook, 0, SCM_C_HOOK_NORMAL); | |
904 | scm_c_hook_init (&scm_after_sweep_c_hook, 0, SCM_C_HOOK_NORMAL); | |
905 | scm_c_hook_init (&scm_after_gc_c_hook, 0, SCM_C_HOOK_NORMAL); | |
906 | } | |
85db4a2c | 907 | |
4a4c9785 | 908 | int |
85db4a2c | 909 | scm_init_storage () |
0f2d19dd | 910 | { |
1be6b49c | 911 | size_t j; |
0f2d19dd | 912 | |
fb50ef08 MD |
913 | /* Fixme: Should use mutexattr from the low-level API. */ |
914 | scm_rec_mutex_init (&scm_i_sweep_mutex, &scm_i_plugin_rec_mutex); | |
915 | ||
0f2d19dd JB |
916 | j = SCM_NUM_PROTECTS; |
917 | while (j) | |
918 | scm_sys_protects[--j] = SCM_BOOL_F; | |
919 | scm_block_gc = 1; | |
4a4c9785 | 920 | |
c8a1bdc4 HWN |
921 | scm_gc_init_freelist(); |
922 | scm_gc_init_malloc (); | |
0f2d19dd JB |
923 | |
924 | j = SCM_HEAP_SEG_SIZE; | |
d6884e63 | 925 | |
c8a1bdc4 | 926 | |
0f2d19dd | 927 | /* Initialise the list of ports. */ |
67329a9e HWN |
928 | scm_i_port_table = (scm_t_port **) |
929 | malloc (sizeof (scm_t_port *) * scm_i_port_table_room); | |
930 | if (!scm_i_port_table) | |
0f2d19dd JB |
931 | return 1; |
932 | ||
a18bcd0e | 933 | #ifdef HAVE_ATEXIT |
c45acc34 | 934 | atexit (cleanup); |
e52ceaac MD |
935 | #else |
936 | #ifdef HAVE_ON_EXIT | |
937 | on_exit (cleanup, 0); | |
938 | #endif | |
a18bcd0e | 939 | #endif |
0f2d19dd | 940 | |
8960e0a0 | 941 | scm_stand_in_procs = SCM_EOL; |
0f2d19dd | 942 | scm_permobjs = SCM_EOL; |
00ffa0e7 | 943 | scm_protects = scm_c_make_hash_table (31); |
6b1b030e | 944 | scm_gc_registered_roots = scm_c_make_hash_table (31); |
d6884e63 | 945 | |
0f2d19dd JB |
946 | return 0; |
947 | } | |
939794ce | 948 | |
0f2d19dd JB |
949 | \f |
950 | ||
939794ce DH |
951 | SCM scm_after_gc_hook; |
952 | ||
939794ce DH |
953 | static SCM gc_async; |
954 | ||
939794ce DH |
955 | /* The function gc_async_thunk causes the execution of the after-gc-hook. It |
956 | * is run after the gc, as soon as the asynchronous events are handled by the | |
957 | * evaluator. | |
958 | */ | |
959 | static SCM | |
960 | gc_async_thunk (void) | |
961 | { | |
962 | scm_c_run_hook (scm_after_gc_hook, SCM_EOL); | |
939794ce DH |
963 | return SCM_UNSPECIFIED; |
964 | } | |
965 | ||
966 | ||
967 | /* The function mark_gc_async is run by the scm_after_gc_c_hook at the end of | |
968 | * the garbage collection. The only purpose of this function is to mark the | |
969 | * gc_async (which will eventually lead to the execution of the | |
970 | * gc_async_thunk). | |
971 | */ | |
972 | static void * | |
e81d98ec DH |
973 | mark_gc_async (void * hook_data SCM_UNUSED, |
974 | void *func_data SCM_UNUSED, | |
975 | void *data SCM_UNUSED) | |
976 | { | |
977 | /* If cell access debugging is enabled, the user may choose to perform | |
978 | * additional garbage collections after an arbitrary number of cell | |
979 | * accesses. We don't want the scheme level after-gc-hook to be performed | |
980 | * for each of these garbage collections for the following reason: The | |
981 | * execution of the after-gc-hook causes cell accesses itself. Thus, if the | |
982 | * after-gc-hook was performed with every gc, and if the gc was performed | |
983 | * after a very small number of cell accesses, then the number of cell | |
984 | * accesses during the execution of the after-gc-hook will suffice to cause | |
985 | * the execution of the next gc. Then, guile would keep executing the | |
986 | * after-gc-hook over and over again, and would never come to do other | |
987 | * things. | |
eae33935 | 988 | * |
e81d98ec DH |
989 | * To overcome this problem, if cell access debugging with additional |
990 | * garbage collections is enabled, the after-gc-hook is never run by the | |
991 | * garbage collecter. When running guile with cell access debugging and the | |
992 | * execution of the after-gc-hook is desired, then it is necessary to run | |
993 | * the hook explicitly from the user code. This has the effect, that from | |
994 | * the scheme level point of view it seems that garbage collection is | |
995 | * performed with a much lower frequency than it actually is. Obviously, | |
996 | * this will not work for code that depends on a fixed one to one | |
997 | * relationship between the execution counts of the C level garbage | |
998 | * collection hooks and the execution count of the scheme level | |
999 | * after-gc-hook. | |
1000 | */ | |
1001 | #if (SCM_DEBUG_CELL_ACCESSES == 1) | |
eab1b259 | 1002 | if (scm_debug_cells_gc_interval == 0) |
e81d98ec DH |
1003 | scm_system_async_mark (gc_async); |
1004 | #else | |
939794ce | 1005 | scm_system_async_mark (gc_async); |
e81d98ec DH |
1006 | #endif |
1007 | ||
939794ce DH |
1008 | return NULL; |
1009 | } | |
1010 | ||
0f2d19dd JB |
1011 | void |
1012 | scm_init_gc () | |
0f2d19dd | 1013 | { |
c8a1bdc4 | 1014 | scm_gc_init_mark (); |
d678e25c | 1015 | |
fde50407 ML |
1016 | scm_after_gc_hook = scm_permanent_object (scm_make_hook (SCM_INUM0)); |
1017 | scm_c_define ("after-gc-hook", scm_after_gc_hook); | |
939794ce | 1018 | |
2592c4c7 MV |
1019 | gc_async = scm_c_make_subr ("%gc-thunk", scm_tc7_subr_0, |
1020 | gc_async_thunk); | |
939794ce DH |
1021 | |
1022 | scm_c_hook_add (&scm_after_gc_c_hook, mark_gc_async, NULL, 0); | |
1023 | ||
a0599745 | 1024 | #include "libguile/gc.x" |
0f2d19dd | 1025 | } |
89e00824 | 1026 | |
c8a1bdc4 HWN |
1027 | |
1028 | void | |
1029 | scm_gc_sweep (void) | |
1030 | #define FUNC_NAME "scm_gc_sweep" | |
1031 | { | |
1032 | scm_i_deprecated_memory_return = 0; | |
1033 | ||
1034 | scm_i_gc_sweep_freelist_reset (&scm_i_master_freelist); | |
1035 | scm_i_gc_sweep_freelist_reset (&scm_i_master_freelist2); | |
1036 | ||
1037 | /* | |
1038 | NOTHING HERE: LAZY SWEEPING ! | |
1039 | */ | |
1040 | scm_i_reset_segments (); | |
1041 | ||
1042 | /* When we move to POSIX threads private freelists should probably | |
1043 | be GC-protected instead. */ | |
9bc4701c MD |
1044 | *SCM_FREELIST_LOC (scm_i_freelist) = SCM_EOL; |
1045 | *SCM_FREELIST_LOC (scm_i_freelist2) = SCM_EOL; | |
392d2833 MD |
1046 | |
1047 | /* Invalidate the freelists of other threads. */ | |
1048 | scm_i_thread_invalidate_freelists (); | |
c8a1bdc4 HWN |
1049 | } |
1050 | ||
1051 | #undef FUNC_NAME | |
1052 | ||
1053 | ||
56495472 | 1054 | |
89e00824 ML |
1055 | /* |
1056 | Local Variables: | |
1057 | c-file-style: "gnu" | |
1058 | End: | |
1059 | */ |