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 2003-2018 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)
 141                 return;
 142
 143         if (!sh->sh_stack) {
 144                 for (i = 0; i <= sh->sh_maxorder - order_start; i++) {
 145                         so = LDAP_LIST_FIRST(&sh->sh_free[i]);
 146                         while (so) {
 147                                 struct slab_object *so_tmp = so;
 148                                 so = LDAP_LIST_NEXT(so, so_link);
 149                                 LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_tmp, so_link);
 150                         }
 151                         ch_free(sh->sh_map[i]);
 152                 }
 153                 ch_free(sh->sh_free);
 154                 ch_free(sh->sh_map);
 155
 156                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 157                 while (so) {
 158                         struct slab_object *so_tmp = so;
 159                         so = LDAP_LIST_NEXT(so, so_link);
 160                         if (!so_tmp->so_blockhead) {
 161                                 LDAP_LIST_REMOVE(so_tmp, so_link);
 162                         }
 163                 }
 164                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 165                 while (so) {
 166                         struct slab_object *so_tmp = so;
 167                         so = LDAP_LIST_NEXT(so, so_link);
 168                         ch_free(so_tmp);
 169                 }
 170         }
 171
 172         if (key != NULL) {
 173                 ber_memfree_x(sh->sh_base, NULL);
 174                 ber_memfree_x(sh, NULL);
 175         }
 176 }
 177
 178 BerMemoryFunctions slap_sl_mfuncs =
 179         { slap_sl_malloc, slap_sl_calloc, slap_sl_realloc, slap_sl_free };
 180
 181 void
 182 slap_sl_mem_init()
 183 {
 184         assert( Align == 1 << Align_log2 );
 185
 186         ber_set_option( NULL, LBER_OPT_MEMORY_FNS, &slap_sl_mfuncs );
 187 }
 188
 189 /* Create, reset or just return the memory context of the current thread. */
 190 void *
 191 slap_sl_mem_create(
 192         ber_len_t size,
 193         int stack,
 194         void *thrctx,
 195         int new
 196 )
 197 {
 198         void *memctx;
 199         struct slab_heap *sh;
 200         ber_len_t size_shift;
 201         struct slab_object *so;
 202         char *base, *newptr;
 203         enum { Base_offset = (unsigned) -sizeof(ber_len_t) % Align };
 204
 205         sh = GET_MEMCTX(thrctx, &memctx);
 206         if ( sh && !new )
 207                 return sh;
 208
 209         /* Round up to doubleword boundary, then make room for initial
 210          * padding, preserving expected available size for pool version */
 211         size = ((size + Align-1) & -Align) + Base_offset;
 212
 213         if (!sh) {
 214                 sh = ch_malloc(sizeof(struct slab_heap));
 215                 base = ch_malloc(size);
 216                 SET_MEMCTX(thrctx, sh, slap_sl_mem_destroy);
 217                 VGMEMP_MARK(base, size);
 218                 VGMEMP_CREATE(sh, 0, 0);
 219         } else {
 220                 slap_sl_mem_destroy(NULL, sh);
 221                 base = sh->sh_base;
 222                 if (size > (ber_len_t) ((char *) sh->sh_end - base)) {
 223                         newptr = ch_realloc(base, size);
 224                         if ( newptr == NULL ) return NULL;
 225                         VGMEMP_CHANGE(sh, base, newptr, size);
 226                         base = newptr;
 227                 }
 228                 VGMEMP_TRIM(sh, base, 0);
 229         }
 230         sh->sh_base = base;
 231         sh->sh_end = base + size;
 232
 233         /* Align (base + head of first block) == first returned block */
 234         base += Base_offset;
 235         size -= Base_offset;
 236
 237         sh->sh_stack = stack;
 238         if (stack) {
 239                 sh->sh_last = base;
 240
 241         } else {
 242                 int i, order = -1, order_end = -1;
 243
 244                 size_shift = size - 1;
 245                 do {
 246                         order_end++;
 247                 } while (size_shift >>= 1);
 248                 order = order_end - order_start + 1;
 249                 sh->sh_maxorder = order_end;
 250
 251                 sh->sh_free = (struct sh_freelist *)
 252                                                 ch_malloc(order * sizeof(struct sh_freelist));
 253                 for (i = 0; i < order; i++) {
 254                         LDAP_LIST_INIT(&sh->sh_free[i]);
 255                 }
 256
 257                 LDAP_LIST_INIT(&sh->sh_sopool);
 258
 259                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 260                         slap_replenish_sopool(sh);
 261                 }
 262                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 263                 LDAP_LIST_REMOVE(so, so_link);
 264                 so->so_ptr = base;
 265
 266                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[order-1], so, so_link);
 267
 268                 sh->sh_map = (unsigned char **)
 269                                         ch_malloc(order * sizeof(unsigned char *));
 270                 for (i = 0; i < order; i++) {
 271                         int shiftamt = order_start + 1 + i;
 272                         int nummaps = size >> shiftamt;
 273                         assert(nummaps);
 274                         nummaps >>= 3;
 275                         if (!nummaps) nummaps = 1;
 276                         sh->sh_map[i] = (unsigned char *) ch_malloc(nummaps);
 277                         memset(sh->sh_map[i], 0, nummaps);
 278                 }
 279         }
 280
 281         return sh;
 282 }
 283
 284 /*
 285  * Assign memory context to thread context. Use NULL to detach
 286  * current memory context from thread. Future users must
 287  * know the context, since ch_free/slap_sl_context() cannot find it.
 288  */
 289 void
 290 slap_sl_mem_setctx(
 291         void *thrctx,
 292         void *memctx
 293 )
 294 {
 295         SET_MEMCTX(thrctx, memctx, slap_sl_mem_destroy);
 296 }
 297
 298 void *
 299 slap_sl_malloc(
 300     ber_len_t   size,
 301     void *ctx
 302 )
 303 {
 304         struct slab_heap *sh = ctx;
 305         ber_len_t *ptr, *newptr;
 306
 307         /* ber_set_option calls us like this */
 308         if (No_sl_malloc || !ctx) {
 309                 newptr = ber_memalloc_x( size, NULL );
 310                 if ( newptr ) return newptr;
 311                 Debug(LDAP_DEBUG_ANY, "slap_sl_malloc of %lu bytes failed\n",
 312                         (unsigned long) size, 0, 0);
 313                 assert( 0 );
 314                 exit( EXIT_FAILURE );
 315         }
 316
 317         /* Add room for head, ensure room for tail when freed, and
 318          * round up to doubleword boundary. */
 319         size = (size + sizeof(ber_len_t) + Align-1 + !size) & -Align;
 320
 321         if (sh->sh_stack) {
 322                 if (size < (ber_len_t) ((char *) sh->sh_end - (char *) sh->sh_last)) {
 323                         newptr = sh->sh_last;
 324                         sh->sh_last = (char *) sh->sh_last + size;
 325                         VGMEMP_ALLOC(sh, newptr, size);
 326                         *newptr++ = size;
 327                         return( (void *)newptr );
 328                 }
 329
 330                 size -= sizeof(ber_len_t);
 331
 332         } else {
 333                 struct slab_object *so_new, *so_left, *so_right;
 334                 ber_len_t size_shift;
 335                 unsigned long diff;
 336                 int i, j, order = -1;
 337
 338                 size_shift = size - 1;
 339                 do {
 340                         order++;
 341                 } while (size_shift >>= 1);
 342
 343                 size -= sizeof(ber_len_t);
 344
 345                 for (i = order; i <= sh->sh_maxorder &&
 346                                 LDAP_LIST_EMPTY(&sh->sh_free[i-order_start]); i++);
 347
 348                 if (i == order) {
 349                         so_new = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 350                         LDAP_LIST_REMOVE(so_new, so_link);
 351                         ptr = so_new->so_ptr;
 352                         diff = (unsigned long)((char*)ptr -
 353                                         (char*)sh->sh_base) >> (order + 1);
 354                         sh->sh_map[order-order_start][diff>>3] |= (1 << (diff & 0x7));
 355                         *ptr++ = size;
 356                         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_new, so_link);
 357                         return((void*)ptr);
 358                 } else if (i <= sh->sh_maxorder) {
 359                         for (j = i; j > order; j--) {
 360                                 so_left = LDAP_LIST_FIRST(&sh->sh_free[j-order_start]);
 361                                 LDAP_LIST_REMOVE(so_left, so_link);
 362                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 363                                         slap_replenish_sopool(sh);
 364                                 }
 365                                 so_right = LDAP_LIST_FIRST(&sh->sh_sopool);
 366                                 LDAP_LIST_REMOVE(so_right, so_link);
 367                                 so_right->so_ptr = (void *)((char *)so_left->so_ptr + (1 << j));
 368                                 if (j == order + 1) {
 369                                         ptr = so_left->so_ptr;
 370                                         diff = (unsigned long)((char*)ptr -
 371                                                         (char*)sh->sh_base) >> (order+1);
 372                                         sh->sh_map[order-order_start][diff>>3] |=
 373                                                         (1 << (diff & 0x7));
 374                                         *ptr++ = size;
 375                                         LDAP_LIST_INSERT_HEAD(
 376                                                         &sh->sh_free[j-1-order_start], so_right, so_link);
 377                                         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_left, so_link);
 378                                         return((void*)ptr);
 379                                 } else {
 380                                         LDAP_LIST_INSERT_HEAD(
 381                                                         &sh->sh_free[j-1-order_start], so_right, so_link);
 382                                         LDAP_LIST_INSERT_HEAD(
 383                                                         &sh->sh_free[j-1-order_start], so_left, so_link);
 384                                 }
 385                         }
 386                 }
 387                 /* FIXME: missing return; guessing we failed... */
 388         }
 389
 390         Debug(LDAP_DEBUG_TRACE,
 391                 "sl_malloc %lu: ch_malloc\n",
 392                 (unsigned long) size, 0, 0);
 393         return ch_malloc(size);
 394 }
 395
 396 #define LIM_SQRT(t) /* some value < sqrt(max value of unsigned type t) */ \
 397         ((0UL|(t)-1) >>31>>31 > 1 ? ((t)1 <<32) - 1 : \
 398          (0UL|(t)-1) >>31 ? 65535U : (0UL|(t)-1) >>15 ? 255U : 15U)
 399
 400 void *
 401 slap_sl_calloc( ber_len_t n, ber_len_t size, void *ctx )
 402 {
 403         void *newptr;
 404         ber_len_t total = n * size;
 405
 406         /* The sqrt test is a slight optimization: often avoids the division */
 407         if ((n | size) <= LIM_SQRT(ber_len_t) || n == 0 || total/n == size) {
 408                 newptr = slap_sl_malloc( total, ctx );
 409                 memset( newptr, 0, n*size );
 410         } else {
 411                 Debug(LDAP_DEBUG_ANY, "slap_sl_calloc(%lu,%lu) out of range\n",
 412                         (unsigned long) n, (unsigned long) size, 0);
 413                 assert(0);
 414                 exit(EXIT_FAILURE);
 415         }
 416         return newptr;
 417 }
 418
 419 void *
 420 slap_sl_realloc(void *ptr, ber_len_t size, void *ctx)
 421 {
 422         struct slab_heap *sh = ctx;
 423         ber_len_t oldsize, *p = (ber_len_t *) ptr, *nextp;
 424         void *newptr;
 425
 426         if (ptr == NULL)
 427                 return slap_sl_malloc(size, ctx);
 428
 429         /* Not our memory? */
 430         if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
 431                 /* Like ch_realloc(), except not trying a new context */
 432                 newptr = ber_memrealloc_x(ptr, size, NULL);
 433                 if (newptr) {
 434                         return newptr;
 435                 }
 436                 Debug(LDAP_DEBUG_ANY, "slap_sl_realloc of %lu bytes failed\n",
 437                         (unsigned long) size, 0, 0);
 438                 assert(0);
 439                 exit( EXIT_FAILURE );
 440         }
 441
 442         if (size == 0) {
 443                 slap_sl_free(ptr, ctx);
 444                 return NULL;
 445         }
 446
 447         oldsize = p[-1];
 448
 449         if (sh->sh_stack) {
 450                 /* Add room for head, round up to doubleword boundary */
 451                 size = (size + sizeof(ber_len_t) + Align-1) & -Align;
 452
 453                 p--;
 454
 455                 /* Never shrink blocks */
 456                 if (size <= oldsize) {
 457                         return ptr;
 458                 }
 459
 460                 oldsize &= -2;
 461                 nextp = (ber_len_t *) ((char *) p + oldsize);
 462
 463                 /* If reallocing the last block, try to grow it */
 464                 if (nextp == sh->sh_last) {
 465                         if (size < (ber_len_t) ((char *) sh->sh_end - (char *) p)) {
 466                                 sh->sh_last = (char *) p + size;
 467                                 p[0] = (p[0] & 1) | size;
 468                                 return ptr;
 469                         }
 470
 471                 /* Nowhere to grow, need to alloc and copy */
 472                 } else {
 473                         /* Slight optimization of the final realloc variant */
 474                         newptr = slap_sl_malloc(size-sizeof(ber_len_t), ctx);
 475                         AC_MEMCPY(newptr, ptr, oldsize-sizeof(ber_len_t));
 476                         /* Not last block, can just mark old region as free */
 477                         nextp[-1] = oldsize;
 478                         nextp[0] |= 1;
 479                         return newptr;
 480                 }
 481
 482                 size -= sizeof(ber_len_t);
 483                 oldsize -= sizeof(ber_len_t);
 484
 485         } else if (oldsize > size) {
 486                 oldsize = size;
 487         }
 488
 489         newptr = slap_sl_malloc(size, ctx);
 490         AC_MEMCPY(newptr, ptr, oldsize);
 491         slap_sl_free(ptr, ctx);
 492         return newptr;
 493 }
 494
 495 void
 496 slap_sl_free(void *ptr, void *ctx)
 497 {
 498         struct slab_heap *sh = ctx;
 499         ber_len_t size;
 500         ber_len_t *p = ptr, *nextp, *tmpp;
 501
 502         if (!ptr)
 503                 return;
 504
 505         if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) {
 506                 ber_memfree_x(ptr, NULL);
 507                 return;
 508         }
 509
 510         size = *(--p);
 511
 512         if (sh->sh_stack) {
 513                 size &= -2;
 514                 nextp = (ber_len_t *) ((char *) p + size);
 515                 if (sh->sh_last != nextp) {
 516                         /* Mark it free: tail = size, head of next block |= 1 */
 517                         nextp[-1] = size;
 518                         nextp[0] |= 1;
 519                         /* We can't tell Valgrind about it yet, because we
 520                          * still need read/write access to this block for
 521                          * when we eventually get to reclaim it.
 522                          */
 523                 } else {
 524                         /* Reclaim freed block(s) off tail */
 525                         while (*p & 1) {
 526                                 p = (ber_len_t *) ((char *) p - p[-1]);
 527                         }
 528                         sh->sh_last = p;
 529                         VGMEMP_TRIM(sh, sh->sh_base,
 530                                 (char *) sh->sh_last - (char *) sh->sh_base);
 531                 }
 532
 533         } else {
 534                 int size_shift, order_size;
 535                 struct slab_object *so;
 536                 unsigned long diff;
 537                 int i, inserted = 0, order = -1;
 538
 539                 size_shift = size + sizeof(ber_len_t) - 1;
 540                 do {
 541                         order++;
 542                 } while (size_shift >>= 1);
 543
 544                 for (i = order, tmpp = p; i <= sh->sh_maxorder; i++) {
 545                         order_size = 1 << (i+1);
 546                         diff = (unsigned long)((char*)tmpp - (char*)sh->sh_base) >> (i+1);
 547                         sh->sh_map[i-order_start][diff>>3] &= (~(1 << (diff & 0x7)));
 548                         if (diff == ((diff>>1)<<1)) {
 549                                 if (!(sh->sh_map[i-order_start][(diff+1)>>3] &
 550                                                 (1<<((diff+1)&0x7)))) {
 551                                         so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 552                                         while (so) {
 553                                                 if ((char*)so->so_ptr == (char*)tmpp) {
 554                                                         LDAP_LIST_REMOVE( so, so_link );
 555                                                 } else if ((char*)so->so_ptr ==
 556                                                                 (char*)tmpp + order_size) {
 557                                                         LDAP_LIST_REMOVE(so, so_link);
 558                                                         break;
 559                                                 }
 560                                                 so = LDAP_LIST_NEXT(so, so_link);
 561                                         }
 562                                         if (so) {
 563                                                 if (i < sh->sh_maxorder) {
 564                                                         inserted = 1;
 565                                                         so->so_ptr = tmpp;
 566                                                         LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1],
 567                                                                         so, so_link);
 568                                                 }
 569                                                 continue;
 570                                         } else {
 571                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 572                                                         slap_replenish_sopool(sh);
 573                                                 }
 574                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 575                                                 LDAP_LIST_REMOVE(so, so_link);
 576                                                 so->so_ptr = tmpp;
 577                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 578                                                                 so, so_link);
 579                                                 break;
 580
 581                                                 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
 582                                                         "free object not found while bit is clear.\n",
 583                                                         0, 0, 0);
 584                                                 assert(so != NULL);
 585
 586                                         }
 587                                 } else {
 588                                         if (!inserted) {
 589                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 590                                                         slap_replenish_sopool(sh);
 591                                                 }
 592                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 593                                                 LDAP_LIST_REMOVE(so, so_link);
 594                                                 so->so_ptr = tmpp;
 595                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 596                                                                 so, so_link);
 597                                         }
 598                                         break;
 599                                 }
 600                         } else {
 601                                 if (!(sh->sh_map[i-order_start][(diff-1)>>3] &
 602                                                 (1<<((diff-1)&0x7)))) {
 603                                         so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 604                                         while (so) {
 605                                                 if ((char*)so->so_ptr == (char*)tmpp) {
 606                                                         LDAP_LIST_REMOVE(so, so_link);
 607                                                 } else if ((char*)tmpp == (char *)so->so_ptr + order_size) {
 608                                                         LDAP_LIST_REMOVE(so, so_link);
 609                                                         tmpp = so->so_ptr;
 610                                                         break;
 611                                                 }
 612                                                 so = LDAP_LIST_NEXT(so, so_link);
 613                                         }
 614                                         if (so) {
 615                                                 if (i < sh->sh_maxorder) {
 616                                                         inserted = 1;
 617                                                         LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1],                                                                    so, so_link);
 618                                                         continue;
 619                                                 }
 620                                         } else {
 621                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 622                                                         slap_replenish_sopool(sh);
 623                                                 }
 624                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 625                                                 LDAP_LIST_REMOVE(so, so_link);
 626                                                 so->so_ptr = tmpp;
 627                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 628                                                                 so, so_link);
 629                                                 break;
 630
 631                                                 Debug(LDAP_DEBUG_TRACE, "slap_sl_free: "
 632                                                         "free object not found while bit is clear.\n",
 633                                                         0, 0, 0 );
 634                                                 assert(so != NULL);
 635
 636                                         }
 637                                 } else {
 638                                         if ( !inserted ) {
 639                                                 if (LDAP_LIST_EMPTY(&sh->sh_sopool)) {
 640                                                         slap_replenish_sopool(sh);
 641                                                 }
 642                                                 so = LDAP_LIST_FIRST(&sh->sh_sopool);
 643                                                 LDAP_LIST_REMOVE(so, so_link);
 644                                                 so->so_ptr = tmpp;
 645                                                 LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start],
 646                                                                 so, so_link);
 647                                         }
 648                                         break;
 649                                 }
 650                         }
 651                 }
 652         }
 653 }
 654
 655 void
 656 slap_sl_release( void *ptr, void *ctx )
 657 {
 658         struct slab_heap *sh = ctx;
 659         if ( sh && ptr >= sh->sh_base && ptr <= sh->sh_end )
 660                 sh->sh_last = ptr;
 661 }
 662
 663 void *
 664 slap_sl_mark( void *ctx )
 665 {
 666         struct slab_heap *sh = ctx;
 667         return sh->sh_last;
 668 }
 669
 670 /*
 671  * Return the memory context of the current thread if the given block of
 672  * memory belongs to it, otherwise return NULL.
 673  */
 674 void *
 675 slap_sl_context( void *ptr )
 676 {
 677         void *memctx;
 678         struct slab_heap *sh;
 679
 680         if ( slapMode & SLAP_TOOL_MODE ) return NULL;
 681
 682         sh = GET_MEMCTX(ldap_pvt_thread_pool_context(), &memctx);
 683         if (sh && ptr >= sh->sh_base && ptr <= sh->sh_end) {
 684                 return sh;
 685         }
 686         return NULL;
 687 }
 688
 689 static struct slab_object *
 690 slap_replenish_sopool(
 691     struct slab_heap* sh
 692 )
 693 {
 694     struct slab_object *so_block;
 695     int i;
 696
 697     so_block = (struct slab_object *)ch_malloc(
 698                     SLAP_SLAB_SOBLOCK * sizeof(struct slab_object));
 699
 700     if ( so_block == NULL ) {
 701         return NULL;
 702     }
 703
 704     so_block[0].so_blockhead = 1;
 705     LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[0], so_link);
 706     for (i = 1; i < SLAP_SLAB_SOBLOCK; i++) {
 707         so_block[i].so_blockhead = 0;
 708         LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[i], so_link );
 709     }
 710
 711     return so_block;
 712 }
 713
 714 #ifdef SLAPD_UNUSED
 715 static void
 716 print_slheap(int level, void *ctx)
 717 {
 718         struct slab_heap *sh = ctx;
 719         struct slab_object *so;
 720         int i, j, once = 0;
 721
 722         if (!ctx) {
 723                 Debug(level, "NULL memctx\n", 0, 0, 0);
 724                 return;
 725         }
 726
 727         Debug(level, "sh->sh_maxorder=%d\n", sh->sh_maxorder, 0, 0);
 728
 729         for (i = order_start; i <= sh->sh_maxorder; i++) {
 730                 once = 0;
 731                 Debug(level, "order=%d\n", i, 0, 0);
 732                 for (j = 0; j < (1<<(sh->sh_maxorder-i))/8; j++) {
 733                         Debug(level, "%02x ", sh->sh_map[i-order_start][j], 0, 0);
 734                         once = 1;
 735                 }
 736                 if (!once) {
 737                         Debug(level, "%02x ", sh->sh_map[i-order_start][0], 0, 0);
 738                 }
 739                 Debug(level, "\n", 0, 0, 0);
 740                 Debug(level, "free list:\n", 0, 0, 0);
 741                 so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]);
 742                 while (so) {
 743                         Debug(level, "%p\n", so->so_ptr, 0, 0);
 744                         so = LDAP_LIST_NEXT(so, so_link);
 745                 }
 746         }
 747 }
 748 #endif