1 /* sl_malloc.c - malloc routines using a per-thread slab */
3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
5 * Copyright 2003-2011 The OpenLDAP Foundation.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted only as authorized by the OpenLDAP
12 * A copy of this license is available in the file LICENSE in the
13 * top-level directory of the distribution or, alternatively, at
14 * <http://www.OpenLDAP.org/license.html>.
20 #include <ac/string.h>
25 Align = 2 * sizeof(int),
26 Align_log2 = 1 + (Align>2) + (Align>4) + (Align>8) + (Align>16),
27 order_start = Align_log2 - 1,
31 static struct slab_object * slap_replenish_sopool(struct slab_heap* sh);
33 static void print_slheap(int level, void *ctx);
36 /* Destroy the context, or if key==NULL clean it up for reuse. */
43 struct slab_heap *sh = data;
44 struct slab_object *so;
48 for (i = 0; i <= sh->sh_maxorder - order_start; i++) {
49 so = LDAP_LIST_FIRST(&sh->sh_free[i]);
51 struct slab_object *so_tmp = so;
52 so = LDAP_LIST_NEXT(so, so_link);
53 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_tmp, so_link);
55 ch_free(sh->sh_map[i]);
60 so = LDAP_LIST_FIRST(&sh->sh_sopool);
62 struct slab_object *so_tmp = so;
63 so = LDAP_LIST_NEXT(so, so_link);
64 if (!so_tmp->so_blockhead) {
65 LDAP_LIST_REMOVE(so_tmp, so_link);
68 so = LDAP_LIST_FIRST(&sh->sh_sopool);
70 struct slab_object *so_tmp = so;
71 so = LDAP_LIST_NEXT(so, so_link);
77 ber_memfree_x(sh->sh_base, NULL);
78 ber_memfree_x(sh, NULL);
82 BerMemoryFunctions slap_sl_mfuncs =
83 { slap_sl_malloc, slap_sl_calloc, slap_sl_realloc, slap_sl_free };
88 assert( Align == 1 << Align_log2 );
89 /* Adding head+tail preserves alignment */
90 assert( 2*sizeof(ber_len_t) % Align == 0 );
92 ber_set_option( NULL, LBER_OPT_MEMORY_FNS, &slap_sl_mfuncs );
96 static struct slab_heap *slheap;
99 /* This allocator always returns memory aligned on a 2-int boundary.
101 * The stack-based allocator stores the size as a ber_len_t at both
102 * the head and tail of the allocated block. When freeing a block, the
103 * tail length is ORed with 1 to mark it as free. Freed space can only
104 * be reclaimed from the tail forward. If the tail block is never freed,
105 * nothing else will be reclaimed until the slab is reset...
115 struct slab_heap *sh;
116 ber_len_t size_shift;
117 struct slab_object *so;
123 ldap_pvt_thread_pool_getkey(
124 ctx, (void *)slap_sl_mem_init, &sh_tmp, NULL );
131 /* round up to doubleword boundary */
132 size = (size + Align-1) & -Align;
135 sh = ch_malloc(sizeof(struct slab_heap));
136 sh->sh_base = ch_malloc(size);
140 ldap_pvt_thread_pool_setkey(ctx, (void *)slap_sl_mem_init,
141 (void *)sh, slap_sl_mem_destroy, NULL, NULL);
144 slap_sl_mem_destroy(NULL, sh);
145 if ( size > (char *)sh->sh_end - (char *)sh->sh_base ) {
148 newptr = ch_realloc( sh->sh_base, size );
149 if ( newptr == NULL ) return NULL;
150 sh->sh_base = newptr;
153 sh->sh_end = (char *) sh->sh_base + size;
155 sh->sh_stack = stack;
157 /* insert dummy len */
159 ber_len_t *i = sh->sh_base;
164 int i, order = -1, order_end = -1;
166 size_shift = size - 1;
169 } while (size_shift >>= 1);
170 order = order_end - order_start + 1;
171 sh->sh_maxorder = order_end;
173 sh->sh_free = (struct sh_freelist *)
174 ch_malloc(order * sizeof(struct sh_freelist));
175 for (i = 0; i < order; i++) {
176 LDAP_LIST_INIT(&sh->sh_free[i]);
179 LDAP_LIST_INIT(&sh->sh_sopool);
181 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
182 slap_replenish_sopool(sh);
184 so = LDAP_LIST_FIRST(&sh->sh_sopool);
185 LDAP_LIST_REMOVE(so, so_link);
186 so->so_ptr = sh->sh_base;
188 LDAP_LIST_INSERT_HEAD(&sh->sh_free[order-1], so, so_link);
190 sh->sh_map = (unsigned char **)
191 ch_malloc(order * sizeof(unsigned char *));
192 for (i = 0; i < order; i++) {
193 int shiftamt = order_start + 1 + i;
194 int nummaps = size >> shiftamt;
197 if (!nummaps) nummaps = 1;
198 sh->sh_map[i] = (unsigned char *) ch_malloc(nummaps);
199 memset(sh->sh_map[i], 0, nummaps);
214 /* separate from context */
215 ldap_pvt_thread_pool_setkey( ctx, (void *)slap_sl_mem_init,
216 NULL, 0, NULL, NULL );
226 struct slab_heap *sh = ctx;
227 ber_len_t *ptr, *newptr;
229 #ifdef SLAP_NO_SL_MALLOC
230 newptr = ber_memalloc_x( size, NULL );
231 if ( newptr ) return newptr;
233 exit( EXIT_FAILURE );
236 /* ber_set_option calls us like this */
238 newptr = ber_memalloc_x( size, NULL );
239 if ( newptr ) return newptr;
241 exit( EXIT_FAILURE );
244 /* round up to doubleword boundary, plus space for len at head and tail */
245 size = (size + 2*sizeof(ber_len_t) + Align-1) & -Align;
248 if ((char *)sh->sh_last + size >= (char *)sh->sh_end) {
249 Debug(LDAP_DEBUG_TRACE,
250 "slap_sl_malloc of %lu bytes failed, using ch_malloc\n",
252 return ch_malloc(size);
254 newptr = sh->sh_last;
255 sh->sh_last = (char *) sh->sh_last + size;
256 size -= sizeof(ber_len_t);
258 *(ber_len_t *)((char *)sh->sh_last - sizeof(ber_len_t)) = size;
259 return( (void *)newptr );
261 struct slab_object *so_new, *so_left, *so_right;
262 ber_len_t size_shift;
264 int i, j, order = -1;
266 size_shift = size - 1;
269 } while (size_shift >>= 1);
271 for (i = order; i <= sh->sh_maxorder &&
272 LDAP_LIST_EMPTY(&sh->sh_free[i-order_start]); i++);
275 so_new = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
276 LDAP_LIST_REMOVE(so_new, so_link);
277 ptr = so_new->so_ptr;
278 diff = (unsigned long)((char*)ptr -
279 (char*)sh->sh_base) >> (order + 1);
280 sh->sh_map[order-order_start][diff>>3] |= (1 << (diff & 0x7));
281 *ptr++ = size - sizeof(ber_len_t);
282 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_new, so_link);
284 } else if (i <= sh->sh_maxorder) {
285 for (j = i; j > order; j--) {
286 so_left = LDAP_LIST_FIRST(&sh->sh_free[j-order_start]);
287 LDAP_LIST_REMOVE(so_left, so_link);
288 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
289 slap_replenish_sopool(sh);
291 so_right = LDAP_LIST_FIRST(&sh->sh_sopool);
292 LDAP_LIST_REMOVE(so_right, so_link);
293 so_right->so_ptr = (void *)((char *)so_left->so_ptr + (1 << j));
294 if (j == order + 1) {
295 ptr = so_left->so_ptr;
296 diff = (unsigned long)((char*)ptr -
297 (char*)sh->sh_base) >> (order+1);
298 sh->sh_map[order-order_start][diff>>3] |=
300 *ptr++ = size - sizeof(ber_len_t);
301 LDAP_LIST_INSERT_HEAD(
302 &sh->sh_free[j-1-order_start], so_right, so_link);
303 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_left, so_link);
306 LDAP_LIST_INSERT_HEAD(
307 &sh->sh_free[j-1-order_start], so_right, so_link);
308 LDAP_LIST_INSERT_HEAD(
309 &sh->sh_free[j-1-order_start], so_left, so_link);
313 Debug( LDAP_DEBUG_TRACE,
314 "sl_malloc %lu: ch_malloc\n",
316 return (void*)ch_malloc(size);
320 /* FIXME: missing return; guessing... */
325 slap_sl_calloc( ber_len_t n, ber_len_t size, void *ctx )
329 newptr = slap_sl_malloc( n*size, ctx );
331 memset( newptr, 0, n*size );
337 slap_sl_realloc(void *ptr, ber_len_t size, void *ctx)
339 struct slab_heap *sh = ctx;
340 ber_len_t oldsize, *p = (ber_len_t *) ptr;
344 return slap_sl_malloc(size, ctx);
346 #ifdef SLAP_NO_SL_MALLOC
347 newptr = ber_memrealloc_x( ptr, size, NULL );
348 if ( newptr ) return newptr;
350 exit( EXIT_FAILURE );
353 /* Not our memory? */
354 if (!sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
355 /* duplicate of realloc behavior, oh well */
356 newptr = ber_memrealloc_x(ptr, size, NULL);
360 Debug(LDAP_DEBUG_ANY, "ch_realloc of %lu bytes failed\n",
363 exit( EXIT_FAILURE );
367 slap_sl_free(ptr, ctx);
374 /* Round up to doubleword boundary, add room for head */
375 size = ((size + Align-1) & -Align) + sizeof( ber_len_t );
379 /* Never shrink blocks */
380 if (size <= oldsize) {
383 /* If reallocing the last block, try to grow it */
384 } else if ((char *) ptr + oldsize == sh->sh_last) {
385 if (size < (char *) sh->sh_end - (char *) ptr) {
386 sh->sh_last = (char *) ptr + size;
388 p[size/sizeof(ber_len_t)] = size;
392 /* Nowhere to grow, need to alloc and copy */
394 /* Slight optimization of the final realloc variant */
395 size -= sizeof(ber_len_t);
396 oldsize -= sizeof(ber_len_t);
397 newptr = slap_sl_malloc(size, ctx);
398 AC_MEMCPY(newptr, ptr, oldsize);
399 /* Not last block, can just mark old region as free */
400 p[p[0]/sizeof(ber_len_t)] |= 1;
404 size -= sizeof(ber_len_t);
405 oldsize -= sizeof(ber_len_t);
407 } else if (oldsize > size) {
411 newptr = slap_sl_malloc(size, ctx);
412 AC_MEMCPY(newptr, ptr, oldsize);
413 slap_sl_free(ptr, ctx);
418 slap_sl_free(void *ptr, void *ctx)
420 struct slab_heap *sh = ctx;
422 ber_len_t *p = (ber_len_t *)ptr, *tmpp;
427 #ifdef SLAP_NO_SL_MALLOC
428 ber_memfree_x( ptr, NULL );
432 if (!sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
433 ber_memfree_x(ptr, NULL);
435 } else if (sh->sh_stack) {
437 p = (ber_len_t *) ((char *) ptr + size);
440 /* reclaim free space off tail */
441 if (sh->sh_last == p) {
443 p = (ber_len_t *) ((char *) p - size + 1) - 1;
450 int size_shift, order_size;
451 struct slab_object *so;
453 int i, inserted = 0, order = -1;
456 size_shift = size + sizeof(ber_len_t) - 1;
459 } while (size_shift >>= 1);
461 for (i = order, tmpp = p; i <= sh->sh_maxorder; i++) {
462 order_size = 1 << (i+1);
463 diff = (unsigned long)((char*)tmpp - (char*)sh->sh_base) >> (i+1);
464 sh->sh_map[i-order_start][diff>>3] &= (~(1 << (diff & 0x7)));
465 if (diff == ((diff>>1)<<1)) {
466 if (!(sh->sh_map[i-order_start][(diff+1)>>3] &
467 (1<<((diff+1)&0x7)))) {
468 so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
470 if ((char*)so->so_ptr == (char*)tmpp) {
471 LDAP_LIST_REMOVE( so, so_link );
472 } else if ((char*)so->so_ptr ==
473 (char*)tmpp + order_size) {
474 LDAP_LIST_REMOVE(so, so_link);
477 so = LDAP_LIST_NEXT(so, so_link);
480 if (i < sh->sh_maxorder) {
483 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1],
488 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
489 slap_replenish_sopool(sh);
491 so = LDAP_LIST_FIRST(&sh->sh_sopool);
492 LDAP_LIST_REMOVE(so, so_link);
494 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
498 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
499 "free object not found while bit is clear.\n",
506 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
507 slap_replenish_sopool(sh);
509 so = LDAP_LIST_FIRST(&sh->sh_sopool);
510 LDAP_LIST_REMOVE(so, so_link);
512 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
518 if (!(sh->sh_map[i-order_start][(diff-1)>>3] &
519 (1<<((diff-1)&0x7)))) {
520 so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
522 if ((char*)so->so_ptr == (char*)tmpp) {
523 LDAP_LIST_REMOVE(so, so_link);
524 } else if ((char*)tmpp == (char *)so->so_ptr + order_size) {
525 LDAP_LIST_REMOVE(so, so_link);
529 so = LDAP_LIST_NEXT(so, so_link);
532 if (i < sh->sh_maxorder) {
534 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1], so, so_link);
538 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
539 slap_replenish_sopool(sh);
541 so = LDAP_LIST_FIRST(&sh->sh_sopool);
542 LDAP_LIST_REMOVE(so, so_link);
544 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
548 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
549 "free object not found while bit is clear.\n",
556 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
557 slap_replenish_sopool(sh);
559 so = LDAP_LIST_FIRST(&sh->sh_sopool);
560 LDAP_LIST_REMOVE(so, so_link);
562 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
573 slap_sl_context( void *ptr )
575 struct slab_heap *sh;
578 if ( slapMode & SLAP_TOOL_MODE ) return NULL;
583 ctx = ldap_pvt_thread_pool_context();
586 ldap_pvt_thread_pool_getkey(
587 ctx, (void *)slap_sl_mem_init, &sh_tmp, NULL);
591 if (sh && ptr >= sh->sh_base && ptr <= sh->sh_end) {
597 static struct slab_object *
598 slap_replenish_sopool(
602 struct slab_object *so_block;
605 so_block = (struct slab_object *)ch_malloc(
606 SLAP_SLAB_SOBLOCK * sizeof(struct slab_object));
608 if ( so_block == NULL ) {
612 so_block[0].so_blockhead = 1;
613 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[0], so_link);
614 for (i = 1; i < SLAP_SLAB_SOBLOCK; i++) {
615 so_block[i].so_blockhead = 0;
616 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[i], so_link );
624 print_slheap(int level, void *ctx)
626 struct slab_heap *sh = ctx;
627 struct slab_object *so;
631 Debug(level, "NULL memctx\n", 0, 0, 0);
635 Debug(level, "sh->sh_maxorder=%d\n", sh->sh_maxorder, 0, 0);
637 for (i = order_start; i <= sh->sh_maxorder; i++) {
639 Debug(level, "order=%d\n", i, 0, 0);
640 for (j = 0; j < (1<<(sh->sh_maxorder-i))/8; j++) {
641 Debug(level, "%02x ", sh->sh_map[i-order_start][j], 0, 0);
645 Debug(level, "%02x ", sh->sh_map[i-order_start][0], 0, 0);
647 Debug(level, "\n", 0, 0, 0);
648 Debug(level, "free list:\n", 0, 0, 0);
649 so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
651 Debug(level, "%lx\n", (unsigned long) so->so_ptr, 0, 0);
652 so = LDAP_LIST_NEXT(so, so_link);