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 2003-2013 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 #ifdef USE_VALGRIND
  25 /* Get debugging help from Valgrind */
  26 #include <valgrind/memcheck.h>
  27 #define VGMEMP_MARK(m,s)        VALGRIND_MAKE_MEM_NOACCESS(m,s)
  28 #define VGMEMP_CREATE(h,r,z)    VALGRIND_CREATE_MEMPOOL(h,r,z)
  29 #define VGMEMP_TRIM(h,a,s)      VALGRIND_MEMPOOL_TRIM(h,a,s)
  30 #define VGMEMP_ALLOC(h,a,s)     VALGRIND_MEMPOOL_ALLOC(h,a,s)
  31 #define VGMEMP_CHANGE(h,a,b,s)  VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
  32 #else
  33 #define VGMEMP_MARK(m,s)
  34 #define VGMEMP_CREATE(h,r,z)
  35 #define VGMEMP_TRIM(h,a,s)
  36 #define VGMEMP_ALLOC(h,a,s)
  37 #define VGMEMP_CHANGE(h,a,b,s)
  38 #endif
  39
  40 /*
  41  * This allocator returns temporary memory from a slab in a given memory
  42  * context, aligned on a 2-int boundary.  It cannot be used for data
  43  * which will outlive the task allocating it.
  44  *
  45  * A new memory context attaches to the creator's thread context, if any.
  46  * Threads cannot use other threads' memory contexts; there are no locks.
  47  *
  48  * The caller of slap_sl_malloc, usually a thread pool task, must
  49  * slap_sl_free the memory before finishing: New tasks reuse the context
  50  * and normally reset it, reclaiming memory left over from last task.
  51  *
  52  * The allocator helps memory fragmentation, speed and memory leaks.
  53  * It is not (yet) reliable as a garbage collector:
  54  *
  55  * It falls back to context NULL - plain ber_memalloc() - when the
  56  * context's slab is full.  A reset does not reclaim such memory.
  57  * Conversely, free/realloc of data not from the given context assumes
  58  * context NULL.  The data must not belong to another memory context.
  59  *
  60  * Code which has lost track of the current memory context can try
  61  * slap_sl_context() or ch_malloc.c:ch_free/ch_realloc().
  62  *
  63  * Allocations cannot yet return failure.  Like ch_malloc, they succeed
  64  * or abort slapd.  This will change, do fix code which assumes success.
  65  */
  66
  67 /*
  68  * The stack-based allocator stores (ber_len_t)sizeof(head+block) at
  69  * allocated blocks' head - and in freed blocks also at the tail, marked
  70  * by ORing *next* block's head with 1.  Freed blocks are only reclaimed
  71  * from the last block forward.  This is fast, but when a block is never
  72  * freed, older blocks will not be reclaimed until the slab is reset...
  73  */
  74
  75 #ifdef SLAP_NO_SL_MALLOC /* Useful with memory debuggers like Valgrind */
  76 enum { No_sl_malloc = 1 };
  77 #else
  78 enum { No_sl_malloc = 0 };
  79 #endif
  80
  81 #define SLAP_SLAB_SOBLOCK 64
  82
  83 struct slab_object {
  84     void *so_ptr;
  85         int so_blockhead;
  86     LDAP_LIST_ENTRY(slab_object) so_link;
  87 };
  88
  89 struct slab_heap {
  90     void *sh_base;
  91     void *sh_last;
  92     void *sh_end;
  93         int sh_stack;
  94         int sh_maxorder;
  95     unsigned char **sh_map;
  96     LDAP_LIST_HEAD(sh_freelist, slab_object) *sh_free;
  97         LDAP_LIST_HEAD(sh_so, slab_object) sh_sopool;
  98 };
  99
 100 enum {
 101         Align = sizeof(ber_len_t) > 2*sizeof(int)
 102                 ? sizeof(ber_len_t) : 2*sizeof(int),
 103         Align_log2 = 1 + (Align>2) + (Align>4) + (Align>8) + (Align>16),
 104         order_start = Align_log2 - 1,
 105         pad = Align - 1
 106 };
 107
 108 static struct slab_object * slap_replenish_sopool(struct slab_heap* sh);
 109 #ifdef SLAPD_UNUSED
 110 static void print_slheap(int level, void *ctx);
 111 #endif
 112
 113 /* Keep memory context in a thread-local var, or in a global when no threads */
 114 #ifdef NO_THREADS
 115 static struct slab_heap *slheap;
 116 # define SET_MEMCTX(thrctx, memctx, sfree)      ((void) (slheap = (memctx)))
 117 # define GET_MEMCTX(thrctx, memctxp)            (*(memctxp) = slheap)
 118 #else
 119 # define memctx_key ((void *) slap_sl_mem_init)
 120 # define SET_MEMCTX(thrctx, memctx, kfree) \
 121         ldap_pvt_thread_pool_setkey(thrctx,memctx_key, memctx,kfree, NULL,NULL)
 122 # define GET_MEMCTX(thrctx, memctxp) \
 123         ((void) (*(memctxp) = NULL), \
 124          (void) ldap_pvt_thread_pool_getkey(thrctx,memctx_key, memctxp,NULL), \
 125          *(memctxp))
 126 #endif /* NO_THREADS */
 127
 128
 129 /* Destroy the context, or if key==NULL clean it up for reuse. */
 130 void
 131 slap_sl_mem_destroy(
 132         void *key,
 133         void *data
 134 )
 135 {
 136         struct slab_heap *sh = data;
 137         struct slab_object *so;
 138         int i;
 139
 140         if (!sh->sh_stack) {
 141                 for (i = 0; i <= sh->sh_maxorder - order_start; i++) {
 142                         so = LDAP_LIST_FIRST(&sh->sh_free[i]);
 143                         while (so) {
 144                                 struct slab_object *so_tmp = so;
 145                                 so = LDAP_LIST_NEXT(so, so_link);
 146                                 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_tmp, so_link);
 147                         }
 148                         ch_free(sh->sh_map[i]);
 149                 }
 150                 ch_free(sh->sh_free);
 151                 ch_free(sh->sh_map);
 152
 153                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 154                 while (so) {
 155                         struct slab_object *so_tmp = so;
 156                         so = LDAP_LIST_NEXT(so, so_link);
 157                         if (!so_tmp->so_blockhead) {
 158                                 LDAP_LIST_REMOVE(so_tmp, so_link);
 159                         }
 160                 }
 161                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 162                 while (so) {
 163                         struct slab_object *so_tmp = so;
 164                         so = LDAP_LIST_NEXT(so, so_link);
 165                         ch_free(so_tmp);
 166                 }
 167         }
 168
 169         if (key != NULL) {
 170                 ber_memfree_x(sh->sh_base, NULL);
 171                 ber_memfree_x(sh, NULL);
 172         }
 173 }
 174
 175 BerMemoryFunctions slap_sl_mfuncs =
 176         { slap_sl_malloc, slap_sl_calloc, slap_sl_realloc, slap_sl_free };
 177
 178 void
 179 slap_sl_mem_init()
 180 {
 181         assert( Align == 1 << Align_log2 );
 182
 183         ber_set_option( NULL, LBER_OPT_MEMORY_FNS, &slap_sl_mfuncs );
 184 }
 185
 186 /* Create, reset or just return the memory context of the current thread. */
 187 void *
 188 slap_sl_mem_create(
 189         ber_len_t size,
 190         int stack,
 191         void *thrctx,
 192         int new
 193 )
 194 {
 195         void *memctx;
 196         struct slab_heap *sh;
 197         ber_len_t size_shift;
 198         struct slab_object *so;
 199         char *base, *newptr;
 200         enum { Base_offset = (unsigned) -sizeof(ber_len_t) % Align };
 201
 202         sh = GET_MEMCTX(thrctx, &memctx);
 203         if ( sh && !new )
 204                 return sh;
 205
 206         /* Round up to doubleword boundary, then make room for initial
 207          * padding, preserving expected available size for pool version */
 208         size = ((size + Align-1) & -Align) + Base_offset;
 209
 210         if (!sh) {
 211                 sh = ch_malloc(sizeof(struct slab_heap));
 212                 base = ch_malloc(size);
 213                 SET_MEMCTX(thrctx, sh, slap_sl_mem_destroy);
 214                 VGMEMP_MARK(base, size);
 215                 VGMEMP_CREATE(sh, 0, 0);
 216         } else {
 217                 slap_sl_mem_destroy(NULL, sh);
 218                 base = sh->sh_base;
 219                 if (size > (ber_len_t) ((char *) sh->sh_end - base)) {
 220                         newptr = ch_realloc(base, size);
 221                         if ( newptr == NULL ) return NULL;
 222                         VGMEMP_CHANGE(sh, base, newptr, size);
 223                         base = newptr;
 224                 }
 225                 VGMEMP_TRIM(sh, base, 0);
 226         }
 227         sh->sh_base = base;
 228         sh->sh_end = base + size;
 229
 230         /* Align (base + head of first block) == first returned block */
 231         base += Base_offset;
 232         size -= Base_offset;
 233
 234         sh->sh_stack = stack;
 235         if (stack) {
 236                 sh->sh_last = base;
 237
 238         } else {
 239                 int i, order = -1, order_end = -1;
 240
 241                 size_shift = size - 1;
 242                 do {
 243                         order_end++;
 244                 } while (size_shift >>= 1);
 245                 order = order_end - order_start + 1;
 246                 sh->sh_maxorder = order_end;
 247
 248                 sh->sh_free = (struct sh_freelist *)
 249                                                 ch_malloc(order * sizeof(struct sh_freelist));
 250                 for (i = 0; i < order; i++) {
 251                         LDAP_LIST_INIT(&sh->sh_free[i]);
 252                 }
 253
 254                 LDAP_LIST_INIT(&sh->sh_sopool);
 255
 256                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 257                         slap_replenish_sopool(sh);
 258                 }
 259                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 260                 LDAP_LIST_REMOVE(so, so_link);
 261                 so->so_ptr = base;
 262
 263                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[order-1], so, so_link);
 264
 265                 sh->sh_map = (unsigned char **)
 266                                         ch_malloc(order * sizeof(unsigned char *));
 267                 for (i = 0; i < order; i++) {
 268                         int shiftamt = order_start + 1 + i;
 269                         int nummaps = size >> shiftamt;
 270                         assert(nummaps);
 271                         nummaps >>= 3;
 272                         if (!nummaps) nummaps = 1;
 273                         sh->sh_map[i] = (unsigned char *) ch_malloc(nummaps);
 274                         memset(sh->sh_map[i], 0, nummaps);
 275                 }
 276         }
 277
 278         return sh;
 279 }
 280
 281 /*
 282  * Separate memory context from thread context.  Future users must
 283  * know the context, since ch_free/slap_sl_context() cannot find it.
 284  */
 285 void
 286 slap_sl_mem_detach(
 287         void *thrctx,
 288         void *memctx
 289 )
 290 {
 291         SET_MEMCTX(thrctx, NULL, 0);
 292 }
 293
 294 void *
 295 slap_sl_malloc(
 296     ber_len_t   size,
 297     void *ctx
 298 )
 299 {
 300         struct slab_heap *sh = ctx;
 301         ber_len_t *ptr, *newptr;
 302
 303         /* ber_set_option calls us like this */
 304         if (No_sl_malloc || !ctx) {
 305                 newptr = ber_memalloc_x( size, NULL );
 306                 if ( newptr ) return newptr;
 307                 Debug(LDAP_DEBUG_ANY, "slap_sl_malloc of %lu bytes failed\n",
 308                         (unsigned long) size, 0, 0);
 309                 assert( 0 );
 310                 exit( EXIT_FAILURE );
 311         }
 312
 313         /* Add room for head, ensure room for tail when freed, and
 314          * round up to doubleword boundary. */
 315         size = (size + sizeof(ber_len_t) + Align-1 + !size) & -Align;
 316
 317         if (sh->sh_stack) {
 318                 if (size < (ber_len_t) ((char *) sh->sh_end - (char *) sh->sh_last)) {
 319                         newptr = sh->sh_last;
 320                         sh->sh_last = (char *) sh->sh_last + size;
 321                         VGMEMP_ALLOC(sh, newptr, size);
 322                         *newptr++ = size;
 323                         return( (void *)newptr );
 324                 }
 325
 326                 size -= sizeof(ber_len_t);
 327
 328         } else {
 329                 struct slab_object *so_new, *so_left, *so_right;
 330                 ber_len_t size_shift;
 331                 unsigned long diff;
 332                 int i, j, order = -1;
 333
 334                 size_shift = size - 1;
 335                 do {
 336                         order++;
 337                 } while (size_shift >>= 1);
 338
 339                 size -= sizeof(ber_len_t);
 340
 341                 for (i = order; i <= sh->sh_maxorder &&
 342                                 LDAP_LIST_EMPTY(&sh->sh_free[i-order_start]); i++);
 343
 344                 if (i == order) {
 345                         so_new = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 346                         LDAP_LIST_REMOVE(so_new, so_link);
 347                         ptr = so_new->so_ptr;
 348                         diff = (unsigned long)((char*)ptr -
 349                                         (char*)sh->sh_base) >> (order + 1);
 350                         sh->sh_map[order-order_start][diff>>3] |= (1 << (diff & 0x7));
 351                         *ptr++ = size;
 352                         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_new, so_link);
 353                         return((void*)ptr);
 354                 } else if (i <= sh->sh_maxorder) {
 355                         for (j = i; j > order; j--) {
 356                                 so_left = LDAP_LIST_FIRST(&sh->sh_free[j-order_start]);
 357                                 LDAP_LIST_REMOVE(so_left, so_link);
 358                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 359                                         slap_replenish_sopool(sh);
 360                                 }
 361                                 so_right = LDAP_LIST_FIRST(&sh->sh_sopool);
 362                                 LDAP_LIST_REMOVE(so_right, so_link);
 363                                 so_right->so_ptr = (void *)((char *)so_left->so_ptr + (1 << j));
 364                                 if (j == order + 1) {
 365                                         ptr = so_left->so_ptr;
 366                                         diff = (unsigned long)((char*)ptr -
 367                                                         (char*)sh->sh_base) >> (order+1);
 368                                         sh->sh_map[order-order_start][diff>>3] |=
 369                                                         (1 << (diff & 0x7));
 370                                         *ptr++ = size;
 371                                         LDAP_LIST_INSERT_HEAD(
 372                                                         &sh->sh_free[j-1-order_start], so_right, so_link);
 373                                         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_left, so_link);
 374                                         return((void*)ptr);
 375                                 } else {
 376                                         LDAP_LIST_INSERT_HEAD(
 377                                                         &sh->sh_free[j-1-order_start], so_right, so_link);
 378                                         LDAP_LIST_INSERT_HEAD(
 379                                                         &sh->sh_free[j-1-order_start], so_left, so_link);
 380                                 }
 381                         }
 382                 }
 383                 /* FIXME: missing return; guessing we failed... */
 384         }
 385
 386         Debug(LDAP_DEBUG_TRACE,
 387                 "sl_malloc %lu: ch_malloc\n",
 388                 (unsigned long) size, 0, 0);
 389         return ch_malloc(size);
 390 }
 391
 392 #define LIM_SQRT(t) /* some value < sqrt(max value of unsigned type t) */ \
 393         ((0UL|(t)-1) >>31>>31 > 1 ? ((t)1 <<32) - 1 : \
 394          (0UL|(t)-1) >>31 ? 65535U : (0UL|(t)-1) >>15 ? 255U : 15U)
 395
 396 void *
 397 slap_sl_calloc( ber_len_t n, ber_len_t size, void *ctx )
 398 {
 399         void *newptr;
 400         ber_len_t total = n * size;
 401
 402         /* The sqrt test is a slight optimization: often avoids the division */
 403         if ((n | size) <= LIM_SQRT(ber_len_t) || n == 0 || total/n == size) {
 404                 newptr = slap_sl_malloc( total, ctx );
 405                 memset( newptr, 0, n*size );
 406         } else {
 407                 Debug(LDAP_DEBUG_ANY, "slap_sl_calloc(%lu,%lu) out of range\n",
 408                         (unsigned long) n, (unsigned long) size, 0);
 409                 assert(0);
 410                 exit(EXIT_FAILURE);
 411         }
 412         return newptr;
 413 }
 414
 415 void *
 416 slap_sl_realloc(void *ptr, ber_len_t size, void *ctx)
 417 {
 418         struct slab_heap *sh = ctx;
 419         ber_len_t oldsize, *p = (ber_len_t *) ptr, *nextp;
 420         void *newptr;
 421
 422         if (ptr == NULL)
 423                 return slap_sl_malloc(size, ctx);
 424
 425         /* Not our memory? */
 426         if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
 427                 /* Like ch_realloc(), except not trying a new context */
 428                 newptr = ber_memrealloc_x(ptr, size, NULL);
 429                 if (newptr) {
 430                         return newptr;
 431                 }
 432                 Debug(LDAP_DEBUG_ANY, "slap_sl_realloc of %lu bytes failed\n",
 433                         (unsigned long) size, 0, 0);
 434                 assert(0);
 435                 exit( EXIT_FAILURE );
 436         }
 437
 438         if (size == 0) {
 439                 slap_sl_free(ptr, ctx);
 440                 return NULL;
 441         }
 442
 443         oldsize = p[-1];
 444
 445         if (sh->sh_stack) {
 446                 /* Add room for head, round up to doubleword boundary */
 447                 size = (size + sizeof(ber_len_t) + Align-1) & -Align;
 448
 449                 p--;
 450
 451                 /* Never shrink blocks */
 452                 if (size <= oldsize) {
 453                         return ptr;
 454                 }
 455
 456                 oldsize &= -2;
 457                 nextp = (ber_len_t *) ((char *) p + oldsize);
 458
 459                 /* If reallocing the last block, try to grow it */
 460                 if (nextp == sh->sh_last) {
 461                         if (size < (ber_len_t) ((char *) sh->sh_end - (char *) p)) {
 462                                 sh->sh_last = (char *) p + size;
 463                                 p[0] = (p[0] & 1) | size;
 464                                 return ptr;
 465                         }
 466
 467                 /* Nowhere to grow, need to alloc and copy */
 468                 } else {
 469                         /* Slight optimization of the final realloc variant */
 470                         newptr = slap_sl_malloc(size-sizeof(ber_len_t), ctx);
 471                         AC_MEMCPY(newptr, ptr, oldsize-sizeof(ber_len_t));
 472                         /* Not last block, can just mark old region as free */
 473                         nextp[-1] = oldsize;
 474                         nextp[0] |= 1;
 475                         return newptr;
 476                 }
 477
 478                 size -= sizeof(ber_len_t);
 479                 oldsize -= sizeof(ber_len_t);
 480
 481         } else if (oldsize > size) {
 482                 oldsize = size;
 483         }
 484
 485         newptr = slap_sl_malloc(size, ctx);
 486         AC_MEMCPY(newptr, ptr, oldsize);
 487         slap_sl_free(ptr, ctx);
 488         return newptr;
 489 }
 490
 491 void
 492 slap_sl_free(void *ptr, void *ctx)
 493 {
 494         struct slab_heap *sh = ctx;
 495         ber_len_t size;
 496         ber_len_t *p = ptr, *nextp, *tmpp;
 497
 498         if (!ptr)
 499                 return;
 500
 501         if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
 502                 ber_memfree_x(ptr, NULL);
 503                 return;
 504         }
 505
 506         size = *(--p);
 507
 508         if (sh->sh_stack) {
 509                 size &= -2;
 510                 nextp = (ber_len_t *) ((char *) p + size);
 511                 if (sh->sh_last != nextp) {
 512                         /* Mark it free: tail = size, head of next block |= 1 */
 513                         nextp[-1] = size;
 514                         nextp[0] |= 1;
 515                         /* We can't tell Valgrind about it yet, because we
 516                          * still need read/write access to this block for
 517                          * when we eventually get to reclaim it.
 518                          */
 519                 } else {
 520                         /* Reclaim freed block(s) off tail */
 521                         while (*p & 1) {
 522                                 p = (ber_len_t *) ((char *) p - p[-1]);
 523                         }
 524                         sh->sh_last = p;
 525                         VGMEMP_TRIM(sh, sh->sh_base,
 526                                 (char *) sh->sh_last - (char *) sh->sh_base);
 527                 }
 528
 529         } else {
 530                 int size_shift, order_size;
 531                 struct slab_object *so;
 532                 unsigned long diff;
 533                 int i, inserted = 0, order = -1;
 534
 535                 size_shift = size + sizeof(ber_len_t) - 1;
 536                 do {
 537                         order++;
 538                 } while (size_shift >>= 1);
 539
 540                 for (i = order, tmpp = p; i <= sh->sh_maxorder; i++) {
 541                         order_size = 1 << (i+1);
 542                         diff = (unsigned long)((char*)tmpp - (char*)sh->sh_base) >> (i+1);
 543                         sh->sh_map[i-order_start][diff>>3] &= (~(1 << (diff & 0x7)));
 544                         if (diff == ((diff>>1)<<1)) {
 545                                 if (!(sh->sh_map[i-order_start][(diff+1)>>3] &
 546                                                 (1<<((diff+1)&0x7)))) {
 547                                         so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 548                                         while (so) {
 549                                                 if ((char*)so->so_ptr == (char*)tmpp) {
 550                                                         LDAP_LIST_REMOVE( so, so_link );
 551                                                 } else if ((char*)so->so_ptr ==
 552                                                                 (char*)tmpp + order_size) {
 553                                                         LDAP_LIST_REMOVE(so, so_link);
 554                                                         break;
 555                                                 }
 556                                                 so = LDAP_LIST_NEXT(so, so_link);
 557                                         }
 558                                         if (so) {
 559                                                 if (i < sh->sh_maxorder) {
 560                                                         inserted = 1;
 561                                                         so->so_ptr = tmpp;
 562                                                         LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1],
 563                                                                         so, so_link);
 564                                                 }
 565                                                 continue;
 566                                         } else {
 567                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 568                                                         slap_replenish_sopool(sh);
 569                                                 }
 570                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 571                                                 LDAP_LIST_REMOVE(so, so_link);
 572                                                 so->so_ptr = tmpp;
 573                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 574                                                                 so, so_link);
 575                                                 break;
 576
 577                                                 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
 578                                                         "free object not found while bit is clear.\n",
 579                                                         0, 0, 0);
 580                                                 assert(so != NULL);
 581
 582                                         }
 583                                 } else {
 584                                         if (!inserted) {
 585                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 586                                                         slap_replenish_sopool(sh);
 587                                                 }
 588                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 589                                                 LDAP_LIST_REMOVE(so, so_link);
 590                                                 so->so_ptr = tmpp;
 591                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 592                                                                 so, so_link);
 593                                         }
 594                                         break;
 595                                 }
 596                         } else {
 597                                 if (!(sh->sh_map[i-order_start][(diff-1)>>3] &
 598                                                 (1<<((diff-1)&0x7)))) {
 599                                         so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 600                                         while (so) {
 601                                                 if ((char*)so->so_ptr == (char*)tmpp) {
 602                                                         LDAP_LIST_REMOVE(so, so_link);
 603                                                 } else if ((char*)tmpp == (char *)so->so_ptr + order_size) {
 604                                                         LDAP_LIST_REMOVE(so, so_link);
 605                                                         tmpp = so->so_ptr;
 606                                                         break;
 607                                                 }
 608                                                 so = LDAP_LIST_NEXT(so, so_link);
 609                                         }
 610                                         if (so) {
 611                                                 if (i < sh->sh_maxorder) {
 612                                                         inserted = 1;
 613                                                         LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1],                                                                    so, so_link);
 614                                                         continue;
 615                                                 }
 616                                         } else {
 617                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 618                                                         slap_replenish_sopool(sh);
 619                                                 }
 620                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 621                                                 LDAP_LIST_REMOVE(so, so_link);
 622                                                 so->so_ptr = tmpp;
 623                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 624                                                                 so, so_link);
 625                                                 break;
 626
 627                                                 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
 628                                                         "free object not found while bit is clear.\n",
 629                                                         0, 0, 0 );
 630                                                 assert(so != NULL);
 631
 632                                         }
 633                                 } else {
 634                                         if ( !inserted ) {
 635                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 636                                                         slap_replenish_sopool(sh);
 637                                                 }
 638                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 639                                                 LDAP_LIST_REMOVE(so, so_link);
 640                                                 so->so_ptr = tmpp;
 641                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 642                                                                 so, so_link);
 643                                         }
 644                                         break;
 645                                 }
 646                         }
 647                 }
 648         }
 649 }
 650
 651 /*
 652  * Return the memory context of the current thread if the given block of
 653  * memory belongs to it, otherwise return NULL.
 654  */
 655 void *
 656 slap_sl_context( void *ptr )
 657 {
 658         void *memctx;
 659         struct slab_heap *sh;
 660
 661         if ( slapMode & SLAP_TOOL_MODE ) return NULL;
 662
 663         sh = GET_MEMCTX(ldap_pvt_thread_pool_context(), &memctx);
 664         if (sh && ptr >= sh->sh_base && ptr <= sh->sh_end) {
 665                 return sh;
 666         }
 667         return NULL;
 668 }
 669
 670 static struct slab_object *
 671 slap_replenish_sopool(
 672     struct slab_heap* sh
 673 )
 674 {
 675     struct slab_object *so_block;
 676     int i;
 677
 678     so_block = (struct slab_object *)ch_malloc(
 679                     SLAP_SLAB_SOBLOCK * sizeof(struct slab_object));
 680
 681     if ( so_block == NULL ) {
 682         return NULL;
 683     }
 684
 685     so_block[0].so_blockhead = 1;
 686     LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[0], so_link);
 687     for (i = 1; i < SLAP_SLAB_SOBLOCK; i++) {
 688         so_block[i].so_blockhead = 0;
 689         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[i], so_link );
 690     }
 691
 692     return so_block;
 693 }
 694
 695 #ifdef SLAPD_UNUSED
 696 static void
 697 print_slheap(int level, void *ctx)
 698 {
 699         struct slab_heap *sh = ctx;
 700         struct slab_object *so;
 701         int i, j, once = 0;
 702
 703         if (!ctx) {
 704                 Debug(level, "NULL memctx\n", 0, 0, 0);
 705                 return;
 706         }
 707
 708         Debug(level, "sh->sh_maxorder=%d\n", sh->sh_maxorder, 0, 0);
 709
 710         for (i = order_start; i <= sh->sh_maxorder; i++) {
 711                 once = 0;
 712                 Debug(level, "order=%d\n", i, 0, 0);
 713                 for (j = 0; j < (1<<(sh->sh_maxorder-i))/8; j++) {
 714                         Debug(level, "%02x ", sh->sh_map[i-order_start][j], 0, 0);
 715                         once = 1;
 716                 }
 717                 if (!once) {
 718                         Debug(level, "%02x ", sh->sh_map[i-order_start][0], 0, 0);
 719                 }
 720                 Debug(level, "\n", 0, 0, 0);
 721                 Debug(level, "free list:\n", 0, 0, 0);
 722                 so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 723                 while (so) {
 724                         Debug(level, "%p\n", so->so_ptr, 0, 0);
 725                         so = LDAP_LIST_NEXT(so, so_link);
 726                 }
 727         }
 728 }
 729 #endif