git.sur5r.net Git - openldap/blob - servers/slapd/sl_malloc.c

   1 /* sl_malloc.c - malloc routines using a per-thread slab */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 2003-2011 The OpenLDAP Foundation.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted only as authorized by the OpenLDAP
  10  * Public License.
  11  *
  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>.
  15  */
  16
  17 #include "portable.h"
  18
  19 #include <stdio.h>
  20 #include <ac/string.h>
  21
  22 #include "slap.h"
  23
  24 /*
  25  * This allocator returns temporary memory from a slab in a given memory
  26  * context, aligned on a 2-int boundary.  It cannot be used for data
  27  * which will outlive the task allocating it.
  28  *
  29  * A new memory context attaches to the creator's thread context, if any.
  30  * Threads cannot use other threads' memory contexts; there are no locks.
  31  *
  32  * The caller of slap_sl_malloc, usually a thread pool task, must
  33  * slap_sl_free the memory before finishing: New tasks reuse the context
  34  * and normally reset it, reclaiming memory left over from last task.
  35  *
  36  * The allocator helps memory fragmentation, speed and memory leaks.
  37  * It is not (yet) reliable as a garbage collector:
  38  *
  39  * It falls back to context NULL - plain ber_memalloc() - when the
  40  * context's slab is full.  A reset does not reclaim such memory.
  41  * Conversely, free/realloc of data not from the given context assumes
  42  * context NULL.  The data must not belong to another memory context.
  43  *
  44  * Code which has lost track of the current memory context can try
  45  * slap_sl_context() or ch_malloc.c:ch_free/ch_realloc().
  46  *
  47  * Allocations cannot yet return failure.  Like ch_malloc, they succeed
  48  * or abort slapd.  This will change, do fix code which assumes success.
  49  */
  50
  51 /*
  52  * The stack-based allocator stores (ber_len_t)sizeof(head+block) at
  53  * allocated blocks' head - and in freed blocks also at the tail, marked
  54  * by ORing *next* block's head with 1.  Freed blocks are only reclaimed
  55  * from the last block forward.  This is fast, but when a block is never
  56  * freed, older blocks will not be reclaimed until the slab is reset...
  57  */
  58
  59 #ifdef SLAP_NO_SL_MALLOC /* Useful with memory debuggers like Valgrind */
  60 enum { No_sl_malloc = 1 };
  61 #else
  62 enum { No_sl_malloc = 0 };
  63 #endif
  64
  65 #define SLAP_SLAB_SOBLOCK 64
  66
  67 struct slab_object {
  68     void *so_ptr;
  69         int so_blockhead;
  70     LDAP_LIST_ENTRY(slab_object) so_link;
  71 };
  72
  73 struct slab_heap {
  74     void *sh_base;
  75     void *sh_last;
  76     void *sh_end;
  77         int sh_stack;
  78         int sh_maxorder;
  79     unsigned char **sh_map;
  80     LDAP_LIST_HEAD(sh_freelist, slab_object) *sh_free;
  81         LDAP_LIST_HEAD(sh_so, slab_object) sh_sopool;
  82 };
  83
  84 enum {
  85         Align = sizeof(ber_len_t) > 2*sizeof(int)
  86                 ? sizeof(ber_len_t) : 2*sizeof(int),
  87         Align_log2 = 1 + (Align>2) + (Align>4) + (Align>8) + (Align>16),
  88         order_start = Align_log2 - 1,
  89         pad = Align - 1
  90 };
  91
  92 static struct slab_object * slap_replenish_sopool(struct slab_heap* sh);
  93 #ifdef SLAPD_UNUSED
  94 static void print_slheap(int level, void *ctx);
  95 #endif
  96
  97 /* Keep memory context in a thread-local var, or in a global when no threads */
  98 #ifdef NO_THREADS
  99 static struct slab_heap *slheap;
 100 # define SET_MEMCTX(thrctx, memctx, sfree)      ((void) (slheap = (memctx)))
 101 # define GET_MEMCTX(thrctx, memctxp)            (*(memctxp) = slheap)
 102 #else
 103 # define memctx_key ((void *) slap_sl_mem_init)
 104 # define SET_MEMCTX(thrctx, memctx, kfree) \
 105         ldap_pvt_thread_pool_setkey(thrctx,memctx_key, memctx,kfree, NULL,NULL)
 106 # define GET_MEMCTX(thrctx, memctxp) \
 107         ((void) (*(memctxp) = NULL), \
 108          (void) ldap_pvt_thread_pool_getkey(thrctx,memctx_key, memctxp,NULL), \
 109          *(memctxp))
 110 #endif /* NO_THREADS */
 111
 112
 113 /* Destroy the context, or if key==NULL clean it up for reuse. */
 114 void
 115 slap_sl_mem_destroy(
 116         void *key,
 117         void *data
 118 )
 119 {
 120         struct slab_heap *sh = data;
 121         struct slab_object *so;
 122         int i;
 123
 124         if (!sh->sh_stack) {
 125                 for (i = 0; i <= sh->sh_maxorder - order_start; i++) {
 126                         so = LDAP_LIST_FIRST(&sh->sh_free[i]);
 127                         while (so) {
 128                                 struct slab_object *so_tmp = so;
 129                                 so = LDAP_LIST_NEXT(so, so_link);
 130                                 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_tmp, so_link);
 131                         }
 132                         ch_free(sh->sh_map[i]);
 133                 }
 134                 ch_free(sh->sh_free);
 135                 ch_free(sh->sh_map);
 136
 137                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 138                 while (so) {
 139                         struct slab_object *so_tmp = so;
 140                         so = LDAP_LIST_NEXT(so, so_link);
 141                         if (!so_tmp->so_blockhead) {
 142                                 LDAP_LIST_REMOVE(so_tmp, so_link);
 143                         }
 144                 }
 145                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 146                 while (so) {
 147                         struct slab_object *so_tmp = so;
 148                         so = LDAP_LIST_NEXT(so, so_link);
 149                         ch_free(so_tmp);
 150                 }
 151         }
 152
 153         if (key != NULL) {
 154                 ber_memfree_x(sh->sh_base, NULL);
 155                 ber_memfree_x(sh, NULL);
 156         }
 157 }
 158
 159 BerMemoryFunctions slap_sl_mfuncs =
 160         { slap_sl_malloc, slap_sl_calloc, slap_sl_realloc, slap_sl_free };
 161
 162 void
 163 slap_sl_mem_init()
 164 {
 165         assert( Align == 1 << Align_log2 );
 166
 167         ber_set_option( NULL, LBER_OPT_MEMORY_FNS, &slap_sl_mfuncs );
 168 }
 169
 170 /* Create, reset or just return the memory context of the current thread. */
 171 void *
 172 slap_sl_mem_create(
 173         ber_len_t size,
 174         int stack,
 175         void *thrctx,
 176         int new
 177 )
 178 {
 179         void *memctx;
 180         struct slab_heap *sh;
 181         ber_len_t size_shift;
 182         struct slab_object *so;
 183         char *base, *newptr;
 184         enum { Base_offset = (unsigned) -sizeof(ber_len_t) % Align };
 185
 186         sh = GET_MEMCTX(thrctx, &memctx);
 187         if ( sh && !new )
 188                 return sh;
 189
 190         /* Round up to doubleword boundary, then make room for initial
 191          * padding, preserving expected available size for pool version */
 192         size = ((size + Align-1) & -Align) + Base_offset;
 193
 194         if (!sh) {
 195                 sh = ch_malloc(sizeof(struct slab_heap));
 196                 base = ch_malloc(size);
 197                 SET_MEMCTX(thrctx, sh, slap_sl_mem_destroy);
 198         } else {
 199                 slap_sl_mem_destroy(NULL, sh);
 200                 base = sh->sh_base;
 201                 if (size > (ber_len_t) ((char *) sh->sh_end - base)) {
 202                         newptr = ch_realloc(base, size);
 203                         if ( newptr == NULL ) return NULL;
 204                         base = newptr;
 205                 }
 206         }
 207         sh->sh_base = base;
 208         sh->sh_end = base + size;
 209
 210         /* Align (base + head of first block) == first returned block */
 211         base += Base_offset;
 212         size -= Base_offset;
 213
 214         sh->sh_stack = stack;
 215         if (stack) {
 216                 sh->sh_last = base;
 217
 218         } else {
 219                 int i, order = -1, order_end = -1;
 220
 221                 size_shift = size - 1;
 222                 do {
 223                         order_end++;
 224                 } while (size_shift >>= 1);
 225                 order = order_end - order_start + 1;
 226                 sh->sh_maxorder = order_end;
 227
 228                 sh->sh_free = (struct sh_freelist *)
 229                                                 ch_malloc(order * sizeof(struct sh_freelist));
 230                 for (i = 0; i < order; i++) {
 231                         LDAP_LIST_INIT(&sh->sh_free[i]);
 232                 }
 233
 234                 LDAP_LIST_INIT(&sh->sh_sopool);
 235
 236                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 237                         slap_replenish_sopool(sh);
 238                 }
 239                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 240                 LDAP_LIST_REMOVE(so, so_link);
 241                 so->so_ptr = base;
 242
 243                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[order-1], so, so_link);
 244
 245                 sh->sh_map = (unsigned char **)
 246                                         ch_malloc(order * sizeof(unsigned char *));
 247                 for (i = 0; i < order; i++) {
 248                         int shiftamt = order_start + 1 + i;
 249                         int nummaps = size >> shiftamt;
 250                         assert(nummaps);
 251                         nummaps >>= 3;
 252                         if (!nummaps) nummaps = 1;
 253                         sh->sh_map[i] = (unsigned char *) ch_malloc(nummaps);
 254                         memset(sh->sh_map[i], 0, nummaps);
 255                 }
 256         }
 257
 258         return sh;
 259 }
 260
 261 /*
 262  * Separate memory context from thread context.  Future users must
 263  * know the context, since ch_free/slap_sl_context() cannot find it.
 264  */
 265 void
 266 slap_sl_mem_detach(
 267         void *thrctx,
 268         void *memctx
 269 )
 270 {
 271         SET_MEMCTX(thrctx, NULL, 0);
 272 }
 273
 274 void *
 275 slap_sl_malloc(
 276     ber_len_t   size,
 277     void *ctx
 278 )
 279 {
 280         struct slab_heap *sh = ctx;
 281         ber_len_t *ptr, *newptr;
 282
 283         /* ber_set_option calls us like this */
 284         if (No_sl_malloc || !ctx) {
 285                 newptr = ber_memalloc_x( size, NULL );
 286                 if ( newptr ) return newptr;
 287                 Debug(LDAP_DEBUG_ANY, "slap_sl_malloc of %lu bytes failed\n",
 288                         (unsigned long) size, 0, 0);
 289                 assert( 0 );
 290                 exit( EXIT_FAILURE );
 291         }
 292
 293         /* Add room for head, ensure room for tail when freed, and
 294          * round up to doubleword boundary. */
 295         size = (size + sizeof(ber_len_t) + Align-1 + !size) & -Align;
 296
 297         if (sh->sh_stack) {
 298                 if (size < (ber_len_t) ((char *) sh->sh_end - (char *) sh->sh_last)) {
 299                         newptr = sh->sh_last;
 300                         sh->sh_last = (char *) sh->sh_last + size;
 301                         *newptr++ = size;
 302                         return( (void *)newptr );
 303                 }
 304
 305                 size -= sizeof(ber_len_t);
 306
 307         } else {
 308                 struct slab_object *so_new, *so_left, *so_right;
 309                 ber_len_t size_shift;
 310                 unsigned long diff;
 311                 int i, j, order = -1;
 312
 313                 size_shift = size - 1;
 314                 do {
 315                         order++;
 316                 } while (size_shift >>= 1);
 317
 318                 size -= sizeof(ber_len_t);
 319
 320                 for (i = order; i <= sh->sh_maxorder &&
 321                                 LDAP_LIST_EMPTY(&sh->sh_free[i-order_start]); i++);
 322
 323                 if (i == order) {
 324                         so_new = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 325                         LDAP_LIST_REMOVE(so_new, so_link);
 326                         ptr = so_new->so_ptr;
 327                         diff = (unsigned long)((char*)ptr -
 328                                         (char*)sh->sh_base) >> (order + 1);
 329                         sh->sh_map[order-order_start][diff>>3] |= (1 << (diff & 0x7));
 330                         *ptr++ = size;
 331                         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_new, so_link);
 332                         return((void*)ptr);
 333                 } else if (i <= sh->sh_maxorder) {
 334                         for (j = i; j > order; j--) {
 335                                 so_left = LDAP_LIST_FIRST(&sh->sh_free[j-order_start]);
 336                                 LDAP_LIST_REMOVE(so_left, so_link);
 337                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 338                                         slap_replenish_sopool(sh);
 339                                 }
 340                                 so_right = LDAP_LIST_FIRST(&sh->sh_sopool);
 341                                 LDAP_LIST_REMOVE(so_right, so_link);
 342                                 so_right->so_ptr = (void *)((char *)so_left->so_ptr + (1 << j));
 343                                 if (j == order + 1) {
 344                                         ptr = so_left->so_ptr;
 345                                         diff = (unsigned long)((char*)ptr -
 346                                                         (char*)sh->sh_base) >> (order+1);
 347                                         sh->sh_map[order-order_start][diff>>3] |=
 348                                                         (1 << (diff & 0x7));
 349                                         *ptr++ = size;
 350                                         LDAP_LIST_INSERT_HEAD(
 351                                                         &sh->sh_free[j-1-order_start], so_right, so_link);
 352                                         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_left, so_link);
 353                                         return((void*)ptr);
 354                                 } else {
 355                                         LDAP_LIST_INSERT_HEAD(
 356                                                         &sh->sh_free[j-1-order_start], so_right, so_link);
 357                                         LDAP_LIST_INSERT_HEAD(
 358                                                         &sh->sh_free[j-1-order_start], so_left, so_link);
 359                                 }
 360                         }
 361                 }
 362                 /* FIXME: missing return; guessing we failed... */
 363         }
 364
 365         Debug(LDAP_DEBUG_TRACE,
 366                 "sl_malloc %lu: ch_malloc\n",
 367                 (unsigned long) size, 0, 0);
 368         return ch_malloc(size);
 369 }
 370
 371 #define LIM_SQRT(t) /* some value < sqrt(max value of unsigned type t) */ \
 372         ((0UL|(t)-1) >>31>>31 > 1 ? ((t)1 <<32) - 1 : \
 373          (0UL|(t)-1) >>31 ? 65535U : (0UL|(t)-1) >>15 ? 255U : 15U)
 374
 375 void *
 376 slap_sl_calloc( ber_len_t n, ber_len_t size, void *ctx )
 377 {
 378         void *newptr;
 379         ber_len_t total = n * size;
 380
 381         /* The sqrt test is a slight optimization: often avoids the division */
 382         if ((n | size) <= LIM_SQRT(ber_len_t) || n == 0 || total/n == size) {
 383                 newptr = slap_sl_malloc( total, ctx );
 384                 memset( newptr, 0, n*size );
 385         } else {
 386                 Debug(LDAP_DEBUG_ANY, "slap_sl_calloc(%lu,%lu) out of range\n",
 387                         (unsigned long) n, (unsigned long) size, 0);
 388                 assert(0);
 389                 exit(EXIT_FAILURE);
 390         }
 391         return newptr;
 392 }
 393
 394 void *
 395 slap_sl_realloc(void *ptr, ber_len_t size, void *ctx)
 396 {
 397         struct slab_heap *sh = ctx;
 398         ber_len_t oldsize, *p = (ber_len_t *) ptr, *nextp;
 399         void *newptr;
 400
 401         if (ptr == NULL)
 402                 return slap_sl_malloc(size, ctx);
 403
 404         /* Not our memory? */
 405         if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
 406                 /* Like ch_realloc(), except not trying a new context */
 407                 newptr = ber_memrealloc_x(ptr, size, NULL);
 408                 if (newptr) {
 409                         return newptr;
 410                 }
 411                 Debug(LDAP_DEBUG_ANY, "slap_sl_realloc of %lu bytes failed\n",
 412                         (unsigned long) size, 0, 0);
 413                 assert(0);
 414                 exit( EXIT_FAILURE );
 415         }
 416
 417         if (size == 0) {
 418                 slap_sl_free(ptr, ctx);
 419                 return NULL;
 420         }
 421
 422         oldsize = p[-1];
 423
 424         if (sh->sh_stack) {
 425                 /* Add room for head, round up to doubleword boundary */
 426                 size = (size + sizeof(ber_len_t) + Align-1) & -Align;
 427
 428                 p--;
 429
 430                 /* Never shrink blocks */
 431                 if (size <= oldsize) {
 432                         return ptr;
 433                 }
 434
 435                 oldsize &= -2;
 436                 nextp = (ber_len_t *) ((char *) p + oldsize);
 437
 438                 /* If reallocing the last block, try to grow it */
 439                 if (nextp == sh->sh_last) {
 440                         if (size < (ber_len_t) ((char *) sh->sh_end - (char *) p)) {
 441                                 sh->sh_last = (char *) p + size;
 442                                 p[0] = (p[0] & 1) | size;
 443                                 return ptr;
 444                         }
 445
 446                 /* Nowhere to grow, need to alloc and copy */
 447                 } else {
 448                         /* Slight optimization of the final realloc variant */
 449                         newptr = slap_sl_malloc(size-sizeof(ber_len_t), ctx);
 450                         AC_MEMCPY(newptr, ptr, oldsize-sizeof(ber_len_t));
 451                         /* Not last block, can just mark old region as free */
 452                         nextp[-1] = oldsize;
 453                         nextp[0] |= 1;
 454                         return newptr;
 455                 }
 456
 457                 size -= sizeof(ber_len_t);
 458                 oldsize -= sizeof(ber_len_t);
 459
 460         } else if (oldsize > size) {
 461                 oldsize = size;
 462         }
 463
 464         newptr = slap_sl_malloc(size, ctx);
 465         AC_MEMCPY(newptr, ptr, oldsize);
 466         slap_sl_free(ptr, ctx);
 467         return newptr;
 468 }
 469
 470 void
 471 slap_sl_free(void *ptr, void *ctx)
 472 {
 473         struct slab_heap *sh = ctx;
 474         ber_len_t size;
 475         ber_len_t *p = ptr, *nextp, *tmpp;
 476
 477         if (!ptr)
 478                 return;
 479
 480         if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
 481                 ber_memfree_x(ptr, NULL);
 482                 return;
 483         }
 484
 485         size = *(--p);
 486
 487         if (sh->sh_stack) {
 488                 size &= -2;
 489                 nextp = (ber_len_t *) ((char *) p + size);
 490                 if (sh->sh_last != nextp) {
 491                         /* Mark it free: tail = size, head of next block |= 1 */
 492                         nextp[-1] = size;
 493                         nextp[0] |= 1;
 494                 } else {
 495                         /* Reclaim freed block(s) off tail */
 496                         while (*p & 1) {
 497                                 p = (ber_len_t *) ((char *) p - p[-1]);
 498                         }
 499                         sh->sh_last = p;
 500                 }
 501
 502         } else {
 503                 int size_shift, order_size;
 504                 struct slab_object *so;
 505                 unsigned long diff;
 506                 int i, inserted = 0, order = -1;
 507
 508                 size_shift = size + sizeof(ber_len_t) - 1;
 509                 do {
 510                         order++;
 511                 } while (size_shift >>= 1);
 512
 513                 for (i = order, tmpp = p; i <= sh->sh_maxorder; i++) {
 514                         order_size = 1 << (i+1);
 515                         diff = (unsigned long)((char*)tmpp - (char*)sh->sh_base) >> (i+1);
 516                         sh->sh_map[i-order_start][diff>>3] &= (~(1 << (diff & 0x7)));
 517                         if (diff == ((diff>>1)<<1)) {
 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]);
 521                                         while (so) {
 522                                                 if ((char*)so->so_ptr == (char*)tmpp) {
 523                                                         LDAP_LIST_REMOVE( so, so_link );
 524                                                 } else if ((char*)so->so_ptr ==
 525                                                                 (char*)tmpp + order_size) {
 526                                                         LDAP_LIST_REMOVE(so, so_link);
 527                                                         break;
 528                                                 }
 529                                                 so = LDAP_LIST_NEXT(so, so_link);
 530                                         }
 531                                         if (so) {
 532                                                 if (i < sh->sh_maxorder) {
 533                                                         inserted = 1;
 534                                                         so->so_ptr = tmpp;
 535                                                         LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1],
 536                                                                         so, so_link);
 537                                                 }
 538                                                 continue;
 539                                         } else {
 540                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 541                                                         slap_replenish_sopool(sh);
 542                                                 }
 543                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 544                                                 LDAP_LIST_REMOVE(so, so_link);
 545                                                 so->so_ptr = tmpp;
 546                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 547                                                                 so, so_link);
 548                                                 break;
 549
 550                                                 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
 551                                                         "free object not found while bit is clear.\n",
 552                                                         0, 0, 0);
 553                                                 assert(so != NULL);
 554
 555                                         }
 556                                 } else {
 557                                         if (!inserted) {
 558                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 559                                                         slap_replenish_sopool(sh);
 560                                                 }
 561                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 562                                                 LDAP_LIST_REMOVE(so, so_link);
 563                                                 so->so_ptr = tmpp;
 564                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 565                                                                 so, so_link);
 566                                         }
 567                                         break;
 568                                 }
 569                         } else {
 570                                 if (!(sh->sh_map[i-order_start][(diff-1)>>3] &
 571                                                 (1<<((diff-1)&0x7)))) {
 572                                         so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 573                                         while (so) {
 574                                                 if ((char*)so->so_ptr == (char*)tmpp) {
 575                                                         LDAP_LIST_REMOVE(so, so_link);
 576                                                 } else if ((char*)tmpp == (char *)so->so_ptr + order_size) {
 577                                                         LDAP_LIST_REMOVE(so, so_link);
 578                                                         tmpp = so->so_ptr;
 579                                                         break;
 580                                                 }
 581                                                 so = LDAP_LIST_NEXT(so, so_link);
 582                                         }
 583                                         if (so) {
 584                                                 if (i < sh->sh_maxorder) {
 585                                                         inserted = 1;
 586                                                         LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1],                                                                    so, so_link);
 587                                                         continue;
 588                                                 }
 589                                         } else {
 590                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 591                                                         slap_replenish_sopool(sh);
 592                                                 }
 593                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 594                                                 LDAP_LIST_REMOVE(so, so_link);
 595                                                 so->so_ptr = tmpp;
 596                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 597                                                                 so, so_link);
 598                                                 break;
 599
 600                                                 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
 601                                                         "free object not found while bit is clear.\n",
 602                                                         0, 0, 0 );
 603                                                 assert(so != NULL);
 604
 605                                         }
 606                                 } else {
 607                                         if ( !inserted ) {
 608                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 609                                                         slap_replenish_sopool(sh);
 610                                                 }
 611                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 612                                                 LDAP_LIST_REMOVE(so, so_link);
 613                                                 so->so_ptr = tmpp;
 614                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 615                                                                 so, so_link);
 616                                         }
 617                                         break;
 618                                 }
 619                         }
 620                 }
 621         }
 622 }
 623
 624 /*
 625  * Return the memory context of the current thread if the given block of
 626  * memory belongs to it, otherwise return NULL.
 627  */
 628 void *
 629 slap_sl_context( void *ptr )
 630 {
 631         void *memctx;
 632         struct slab_heap *sh;
 633
 634         if ( slapMode & SLAP_TOOL_MODE ) return NULL;
 635
 636         sh = GET_MEMCTX(ldap_pvt_thread_pool_context(), &memctx);
 637         if (sh && ptr >= sh->sh_base && ptr <= sh->sh_end) {
 638                 return sh;
 639         }
 640         return NULL;
 641 }
 642
 643 static struct slab_object *
 644 slap_replenish_sopool(
 645     struct slab_heap* sh
 646 )
 647 {
 648     struct slab_object *so_block;
 649     int i;
 650
 651     so_block = (struct slab_object *)ch_malloc(
 652                     SLAP_SLAB_SOBLOCK * sizeof(struct slab_object));
 653
 654     if ( so_block == NULL ) {
 655         return NULL;
 656     }
 657
 658     so_block[0].so_blockhead = 1;
 659     LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[0], so_link);
 660     for (i = 1; i < SLAP_SLAB_SOBLOCK; i++) {
 661         so_block[i].so_blockhead = 0;
 662         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[i], so_link );
 663     }
 664
 665     return so_block;
 666 }
 667
 668 #ifdef SLAPD_UNUSED
 669 static void
 670 print_slheap(int level, void *ctx)
 671 {
 672         struct slab_heap *sh = ctx;
 673         struct slab_object *so;
 674         int i, j, once = 0;
 675
 676         if (!ctx) {
 677                 Debug(level, "NULL memctx\n", 0, 0, 0);
 678                 return;
 679         }
 680
 681         Debug(level, "sh->sh_maxorder=%d\n", sh->sh_maxorder, 0, 0);
 682
 683         for (i = order_start; i <= sh->sh_maxorder; i++) {
 684                 once = 0;
 685                 Debug(level, "order=%d\n", i, 0, 0);
 686                 for (j = 0; j < (1<<(sh->sh_maxorder-i))/8; j++) {
 687                         Debug(level, "%02x ", sh->sh_map[i-order_start][j], 0, 0);
 688                         once = 1;
 689                 }
 690                 if (!once) {
 691                         Debug(level, "%02x ", sh->sh_map[i-order_start][0], 0, 0);
 692                 }
 693                 Debug(level, "\n", 0, 0, 0);
 694                 Debug(level, "free list:\n", 0, 0, 0);
 695                 so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 696                 while (so) {
 697                         Debug(level, "%p\n", so->so_ptr, 0, 0);
 698                         so = LDAP_LIST_NEXT(so, so_link);
 699                 }
 700         }
 701 }
 702 #endif