1/* $NetBSD: tpool.c,v 1.2 2021/08/14 16:14:56 christos Exp $ */ 2 3/* $OpenLDAP$ */ 4/* This work is part of OpenLDAP Software <http://www.openldap.org/>. 5 * 6 * Copyright 1998-2021 The OpenLDAP Foundation. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted only as authorized by the OpenLDAP 11 * Public License. 12 * 13 * A copy of this license is available in file LICENSE in the 14 * top-level directory of the distribution or, alternatively, at 15 * <http://www.OpenLDAP.org/license.html>. 16 */ 17 18#include <sys/cdefs.h> 19__RCSID("$NetBSD: tpool.c,v 1.2 2021/08/14 16:14:56 christos Exp $"); 20 21#include "portable.h" 22 23#include <stdio.h> 24 25#include <ac/signal.h> 26#include <ac/stdarg.h> 27#include <ac/stdlib.h> 28#include <ac/string.h> 29#include <ac/time.h> 30#include <ac/errno.h> 31 32#include "ldap-int.h" 33 34#ifdef LDAP_R_COMPILE 35 36#include "ldap_pvt_thread.h" /* Get the thread interface */ 37#include "ldap_queue.h" 38#define LDAP_THREAD_POOL_IMPLEMENTATION 39#include "ldap_thr_debug.h" /* May rename symbols defined below */ 40 41#ifndef LDAP_THREAD_HAVE_TPOOL 42 43#ifndef CACHELINE 44#define CACHELINE 64 45#endif 46 47/* Thread-specific key with data and optional free function */ 48typedef struct ldap_int_tpool_key_s { 49 void *ltk_key; 50 void *ltk_data; 51 ldap_pvt_thread_pool_keyfree_t *ltk_free; 52} ldap_int_tpool_key_t; 53 54/* Max number of thread-specific keys we store per thread. 55 * We don't expect to use many... 56 */ 57#define MAXKEYS 32 58 59/* Max number of threads */ 60#define LDAP_MAXTHR 1024 /* must be a power of 2 */ 61 62/* (Theoretical) max number of pending requests */ 63#define MAX_PENDING (INT_MAX/2) /* INT_MAX - (room to avoid overflow) */ 64 65/* pool->ltp_pause values */ 66enum { NOT_PAUSED = 0, WANT_PAUSE = 1, PAUSED = 2 }; 67 68/* Context: thread ID and thread-specific key/data pairs */ 69typedef struct ldap_int_thread_userctx_s { 70 struct ldap_int_thread_poolq_s *ltu_pq; 71 ldap_pvt_thread_t ltu_id; 72 ldap_int_tpool_key_t ltu_key[MAXKEYS]; 73} ldap_int_thread_userctx_t; 74 75 76/* Simple {thread ID -> context} hash table; key=ctx->ltu_id. 77 * Protected by ldap_pvt_thread_pool_mutex. 78 */ 79static struct { 80 ldap_int_thread_userctx_t *ctx; 81 /* ctx is valid when not NULL or DELETED_THREAD_CTX */ 82# define DELETED_THREAD_CTX (&ldap_int_main_thrctx + 1) /* dummy addr */ 83} thread_keys[LDAP_MAXTHR]; 84 85#define TID_HASH(tid, hash) do { \ 86 unsigned const char *ptr_ = (unsigned const char *)&(tid); \ 87 unsigned i_; \ 88 for (i_ = 0, (hash) = ptr_[0]; ++i_ < sizeof(tid);) \ 89 (hash) += ((hash) << 5) ^ ptr_[i_]; \ 90} while(0) 91 92 93/* Task for a thread to perform */ 94typedef struct ldap_int_thread_task_s { 95 union { 96 LDAP_STAILQ_ENTRY(ldap_int_thread_task_s) q; 97 LDAP_SLIST_ENTRY(ldap_int_thread_task_s) l; 98 } ltt_next; 99 ldap_pvt_thread_start_t *ltt_start_routine; 100 void *ltt_arg; 101 struct ldap_int_thread_poolq_s *ltt_queue; 102} ldap_int_thread_task_t; 103 104typedef LDAP_STAILQ_HEAD(tcq, ldap_int_thread_task_s) ldap_int_tpool_plist_t; 105 106struct ldap_int_thread_poolq_s { 107 void *ltp_free; 108 109 struct ldap_int_thread_pool_s *ltp_pool; 110 111 /* protect members below */ 112 ldap_pvt_thread_mutex_t ltp_mutex; 113 114 /* not paused and something to do for pool_<wrapper/pause/destroy>() 115 * Used for normal pool operation, to synch between submitter and 116 * worker threads. Not used for pauses. In normal operation multiple 117 * queues can rendezvous without acquiring the main pool lock. 118 */ 119 ldap_pvt_thread_cond_t ltp_cond; 120 121 /* ltp_pause == 0 ? <p_pending_list : &empty_pending_list, 122 * maintained to reduce work for pool_wrapper() 123 */ 124 ldap_int_tpool_plist_t *ltp_work_list; 125 126 /* pending tasks, and unused task objects */ 127 ldap_int_tpool_plist_t ltp_pending_list; 128 LDAP_SLIST_HEAD(tcl, ldap_int_thread_task_s) ltp_free_list; 129 130 /* Max number of threads in this queue */ 131 int ltp_max_count; 132 133 /* Max pending + paused + idle tasks, negated when ltp_finishing */ 134 int ltp_max_pending; 135 136 int ltp_pending_count; /* Pending + paused + idle tasks */ 137 int ltp_active_count; /* Active, not paused/idle tasks */ 138 int ltp_open_count; /* Number of threads */ 139 int ltp_starting; /* Currently starting threads */ 140}; 141 142struct ldap_int_thread_pool_s { 143 LDAP_STAILQ_ENTRY(ldap_int_thread_pool_s) ltp_next; 144 145 struct ldap_int_thread_poolq_s **ltp_wqs; 146 147 /* number of poolqs */ 148 int ltp_numqs; 149 150 /* protect members below */ 151 ldap_pvt_thread_mutex_t ltp_mutex; 152 153 /* paused and waiting for resume 154 * When a pause is in effect all workers switch to waiting on 155 * this cond instead of their per-queue cond. 156 */ 157 ldap_pvt_thread_cond_t ltp_cond; 158 159 /* ltp_active_queues < 1 && ltp_pause */ 160 ldap_pvt_thread_cond_t ltp_pcond; 161 162 /* number of active queues */ 163 int ltp_active_queues; 164 165 /* The pool is finishing, waiting for its threads to close. 166 * They close when ltp_pending_list is done. pool_submit() 167 * rejects new tasks. ltp_max_pending = -(its old value). 168 */ 169 int ltp_finishing; 170 171 /* Some active task needs to be the sole active task. 172 * Atomic variable so ldap_pvt_thread_pool_pausing() can read it. 173 */ 174 volatile sig_atomic_t ltp_pause; 175 176 /* Max number of threads in pool */ 177 int ltp_max_count; 178 179 /* Configured max number of threads in pool, 0 for default (LDAP_MAXTHR) */ 180 int ltp_conf_max_count; 181 182 /* Max pending + paused + idle tasks, negated when ltp_finishing */ 183 int ltp_max_pending; 184}; 185 186static ldap_int_tpool_plist_t empty_pending_list = 187 LDAP_STAILQ_HEAD_INITIALIZER(empty_pending_list); 188 189static int ldap_int_has_thread_pool = 0; 190static LDAP_STAILQ_HEAD(tpq, ldap_int_thread_pool_s) 191 ldap_int_thread_pool_list = 192 LDAP_STAILQ_HEAD_INITIALIZER(ldap_int_thread_pool_list); 193 194static ldap_pvt_thread_mutex_t ldap_pvt_thread_pool_mutex; 195 196static void *ldap_int_thread_pool_wrapper( void *pool ); 197 198static ldap_pvt_thread_key_t ldap_tpool_key; 199 200/* Context of the main thread */ 201static ldap_int_thread_userctx_t ldap_int_main_thrctx; 202 203int 204ldap_int_thread_pool_startup ( void ) 205{ 206 ldap_int_main_thrctx.ltu_id = ldap_pvt_thread_self(); 207 ldap_pvt_thread_key_create( &ldap_tpool_key ); 208 return ldap_pvt_thread_mutex_init(&ldap_pvt_thread_pool_mutex); 209} 210 211int 212ldap_int_thread_pool_shutdown ( void ) 213{ 214 struct ldap_int_thread_pool_s *pool; 215 216 while ((pool = LDAP_STAILQ_FIRST(&ldap_int_thread_pool_list)) != NULL) { 217 (ldap_pvt_thread_pool_destroy)(&pool, 0); /* ignore thr_debug macro */ 218 } 219 ldap_pvt_thread_mutex_destroy(&ldap_pvt_thread_pool_mutex); 220 ldap_pvt_thread_key_destroy( ldap_tpool_key ); 221 return(0); 222} 223 224 225/* Create a thread pool */ 226int 227ldap_pvt_thread_pool_init_q ( 228 ldap_pvt_thread_pool_t *tpool, 229 int max_threads, 230 int max_pending, 231 int numqs ) 232{ 233 ldap_pvt_thread_pool_t pool; 234 struct ldap_int_thread_poolq_s *pq; 235 int i, rc, rem_thr, rem_pend; 236 237 /* multiple pools are currently not supported (ITS#4943) */ 238 assert(!ldap_int_has_thread_pool); 239 240 if (! (0 <= max_threads && max_threads <= LDAP_MAXTHR)) 241 max_threads = 0; 242 if (! (1 <= max_pending && max_pending <= MAX_PENDING)) 243 max_pending = MAX_PENDING; 244 245 *tpool = NULL; 246 pool = (ldap_pvt_thread_pool_t) LDAP_CALLOC(1, 247 sizeof(struct ldap_int_thread_pool_s)); 248 249 if (pool == NULL) return(-1); 250 251 pool->ltp_wqs = LDAP_MALLOC(numqs * sizeof(struct ldap_int_thread_poolq_s *)); 252 if (pool->ltp_wqs == NULL) { 253 LDAP_FREE(pool); 254 return(-1); 255 } 256 257 for (i=0; i<numqs; i++) { 258 char *ptr = LDAP_CALLOC(1, sizeof(struct ldap_int_thread_poolq_s) + CACHELINE-1); 259 if (ptr == NULL) { 260 for (--i; i>=0; i--) 261 LDAP_FREE(pool->ltp_wqs[i]->ltp_free); 262 LDAP_FREE(pool->ltp_wqs); 263 LDAP_FREE(pool); 264 return(-1); 265 } 266 pool->ltp_wqs[i] = (struct ldap_int_thread_poolq_s *)(((size_t)ptr + CACHELINE-1) & ~(CACHELINE-1)); 267 pool->ltp_wqs[i]->ltp_free = ptr; 268 } 269 270 pool->ltp_numqs = numqs; 271 pool->ltp_conf_max_count = max_threads; 272 if ( !max_threads ) 273 max_threads = LDAP_MAXTHR; 274 275 rc = ldap_pvt_thread_mutex_init(&pool->ltp_mutex); 276 if (rc != 0) { 277fail: 278 for (i=0; i<numqs; i++) 279 LDAP_FREE(pool->ltp_wqs[i]->ltp_free); 280 LDAP_FREE(pool->ltp_wqs); 281 LDAP_FREE(pool); 282 return(rc); 283 } 284 285 rc = ldap_pvt_thread_cond_init(&pool->ltp_cond); 286 if (rc != 0) 287 goto fail; 288 289 rc = ldap_pvt_thread_cond_init(&pool->ltp_pcond); 290 if (rc != 0) 291 goto fail; 292 293 rem_thr = max_threads % numqs; 294 rem_pend = max_pending % numqs; 295 for ( i=0; i<numqs; i++ ) { 296 pq = pool->ltp_wqs[i]; 297 pq->ltp_pool = pool; 298 rc = ldap_pvt_thread_mutex_init(&pq->ltp_mutex); 299 if (rc != 0) 300 return(rc); 301 rc = ldap_pvt_thread_cond_init(&pq->ltp_cond); 302 if (rc != 0) 303 return(rc); 304 LDAP_STAILQ_INIT(&pq->ltp_pending_list); 305 pq->ltp_work_list = &pq->ltp_pending_list; 306 LDAP_SLIST_INIT(&pq->ltp_free_list); 307 308 pq->ltp_max_count = max_threads / numqs; 309 if ( rem_thr ) { 310 pq->ltp_max_count++; 311 rem_thr--; 312 } 313 pq->ltp_max_pending = max_pending / numqs; 314 if ( rem_pend ) { 315 pq->ltp_max_pending++; 316 rem_pend--; 317 } 318 } 319 320 ldap_int_has_thread_pool = 1; 321 322 pool->ltp_max_count = max_threads; 323 pool->ltp_max_pending = max_pending; 324 325 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex); 326 LDAP_STAILQ_INSERT_TAIL(&ldap_int_thread_pool_list, pool, ltp_next); 327 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex); 328 329 /* Start no threads just yet. That can break if the process forks 330 * later, as slapd does in order to daemonize. On at least POSIX, 331 * only the forking thread would survive in the child. Yet fork() 332 * can't unlock/clean up other threads' locks and data structures, 333 * unless pthread_atfork() handlers have been set up to do so. 334 */ 335 336 *tpool = pool; 337 return(0); 338} 339 340int 341ldap_pvt_thread_pool_init ( 342 ldap_pvt_thread_pool_t *tpool, 343 int max_threads, 344 int max_pending ) 345{ 346 return ldap_pvt_thread_pool_init_q( tpool, max_threads, max_pending, 1 ); 347} 348 349/* Submit a task to be performed by the thread pool */ 350int 351ldap_pvt_thread_pool_submit ( 352 ldap_pvt_thread_pool_t *tpool, 353 ldap_pvt_thread_start_t *start_routine, void *arg ) 354{ 355 return ldap_pvt_thread_pool_submit2( tpool, start_routine, arg, NULL ); 356} 357 358/* Submit a task to be performed by the thread pool */ 359int 360ldap_pvt_thread_pool_submit2 ( 361 ldap_pvt_thread_pool_t *tpool, 362 ldap_pvt_thread_start_t *start_routine, void *arg, 363 void **cookie ) 364{ 365 struct ldap_int_thread_pool_s *pool; 366 struct ldap_int_thread_poolq_s *pq; 367 ldap_int_thread_task_t *task; 368 ldap_pvt_thread_t thr; 369 int i, j; 370 371 if (tpool == NULL) 372 return(-1); 373 374 pool = *tpool; 375 376 if (pool == NULL) 377 return(-1); 378 379 if ( pool->ltp_numqs > 1 ) { 380 int min = pool->ltp_wqs[0]->ltp_max_pending + pool->ltp_wqs[0]->ltp_max_count; 381 int min_x = 0, cnt; 382 for ( i = 0; i < pool->ltp_numqs; i++ ) { 383 /* take first queue that has nothing active */ 384 if ( !pool->ltp_wqs[i]->ltp_active_count ) { 385 min_x = i; 386 break; 387 } 388 cnt = pool->ltp_wqs[i]->ltp_active_count + pool->ltp_wqs[i]->ltp_pending_count; 389 if ( cnt < min ) { 390 min = cnt; 391 min_x = i; 392 } 393 } 394 i = min_x; 395 } else 396 i = 0; 397 398 j = i; 399 while(1) { 400 ldap_pvt_thread_mutex_lock(&pool->ltp_wqs[i]->ltp_mutex); 401 if (pool->ltp_wqs[i]->ltp_pending_count < pool->ltp_wqs[i]->ltp_max_pending) { 402 break; 403 } 404 ldap_pvt_thread_mutex_unlock(&pool->ltp_wqs[i]->ltp_mutex); 405 i++; 406 i %= pool->ltp_numqs; 407 if ( i == j ) 408 return -1; 409 } 410 411 pq = pool->ltp_wqs[i]; 412 task = LDAP_SLIST_FIRST(&pq->ltp_free_list); 413 if (task) { 414 LDAP_SLIST_REMOVE_HEAD(&pq->ltp_free_list, ltt_next.l); 415 } else { 416 task = (ldap_int_thread_task_t *) LDAP_MALLOC(sizeof(*task)); 417 if (task == NULL) 418 goto failed; 419 } 420 421 task->ltt_start_routine = start_routine; 422 task->ltt_arg = arg; 423 task->ltt_queue = pq; 424 if ( cookie ) 425 *cookie = task; 426 427 pq->ltp_pending_count++; 428 LDAP_STAILQ_INSERT_TAIL(&pq->ltp_pending_list, task, ltt_next.q); 429 430 if (pool->ltp_pause) 431 goto done; 432 433 /* should we open (create) a thread? */ 434 if (pq->ltp_open_count < pq->ltp_active_count+pq->ltp_pending_count && 435 pq->ltp_open_count < pq->ltp_max_count) 436 { 437 pq->ltp_starting++; 438 pq->ltp_open_count++; 439 440 if (0 != ldap_pvt_thread_create( 441 &thr, 1, ldap_int_thread_pool_wrapper, pq)) 442 { 443 /* couldn't create thread. back out of 444 * ltp_open_count and check for even worse things. 445 */ 446 pq->ltp_starting--; 447 pq->ltp_open_count--; 448 449 if (pq->ltp_open_count == 0) { 450 /* no open threads at all?!? 451 */ 452 ldap_int_thread_task_t *ptr; 453 454 /* let pool_close know there are no more threads */ 455 ldap_pvt_thread_cond_signal(&pq->ltp_cond); 456 457 LDAP_STAILQ_FOREACH(ptr, &pq->ltp_pending_list, ltt_next.q) 458 if (ptr == task) break; 459 if (ptr == task) { 460 /* no open threads, task not handled, so 461 * back out of ltp_pending_count, free the task, 462 * report the error. 463 */ 464 pq->ltp_pending_count--; 465 LDAP_STAILQ_REMOVE(&pq->ltp_pending_list, task, 466 ldap_int_thread_task_s, ltt_next.q); 467 LDAP_SLIST_INSERT_HEAD(&pq->ltp_free_list, task, 468 ltt_next.l); 469 goto failed; 470 } 471 } 472 /* there is another open thread, so this 473 * task will be handled eventually. 474 */ 475 } 476 } 477 ldap_pvt_thread_cond_signal(&pq->ltp_cond); 478 479 done: 480 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 481 return(0); 482 483 failed: 484 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 485 return(-1); 486} 487 488static void * 489no_task( void *ctx, void *arg ) 490{ 491 return NULL; 492} 493 494/* Cancel a pending task that was previously submitted. 495 * Return 1 if the task was successfully cancelled, 0 if 496 * not found, -1 for invalid parameters 497 */ 498int 499ldap_pvt_thread_pool_retract ( 500 void *cookie ) 501{ 502 ldap_int_thread_task_t *task, *ttmp; 503 struct ldap_int_thread_poolq_s *pq; 504 505 if (cookie == NULL) 506 return(-1); 507 508 ttmp = cookie; 509 pq = ttmp->ltt_queue; 510 if (pq == NULL) 511 return(-1); 512 513 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 514 LDAP_STAILQ_FOREACH(task, &pq->ltp_pending_list, ltt_next.q) 515 if (task == ttmp) { 516 /* Could LDAP_STAILQ_REMOVE the task, but that 517 * walks ltp_pending_list again to find it. 518 */ 519 task->ltt_start_routine = no_task; 520 task->ltt_arg = NULL; 521 break; 522 } 523 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 524 return task != NULL; 525} 526 527/* Walk the pool and allow tasks to be retracted, only to be called while the 528 * pool is paused */ 529int 530ldap_pvt_thread_pool_walk( 531 ldap_pvt_thread_pool_t *tpool, 532 ldap_pvt_thread_start_t *start, 533 ldap_pvt_thread_walk_t *cb, void *arg ) 534{ 535 struct ldap_int_thread_pool_s *pool; 536 struct ldap_int_thread_poolq_s *pq; 537 ldap_int_thread_task_t *task; 538 int i; 539 540 if (tpool == NULL) 541 return(-1); 542 543 pool = *tpool; 544 545 if (pool == NULL) 546 return(-1); 547 548 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 549 assert(pool->ltp_pause == PAUSED); 550 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 551 552 for (i=0; i<pool->ltp_numqs; i++) { 553 pq = pool->ltp_wqs[i]; 554 LDAP_STAILQ_FOREACH(task, &pq->ltp_pending_list, ltt_next.q) { 555 if ( task->ltt_start_routine == start ) { 556 if ( cb( task->ltt_start_routine, task->ltt_arg, arg ) ) { 557 /* retract */ 558 task->ltt_start_routine = no_task; 559 task->ltt_arg = NULL; 560 } 561 } 562 } 563 } 564 return 0; 565} 566 567/* Set number of work queues in this pool. Should not be 568 * more than the number of CPUs. */ 569int 570ldap_pvt_thread_pool_queues( 571 ldap_pvt_thread_pool_t *tpool, 572 int numqs ) 573{ 574 struct ldap_int_thread_pool_s *pool; 575 struct ldap_int_thread_poolq_s *pq; 576 int i, rc, rem_thr, rem_pend; 577 578 if (numqs < 1 || tpool == NULL) 579 return(-1); 580 581 pool = *tpool; 582 583 if (pool == NULL) 584 return(-1); 585 586 if (numqs < pool->ltp_numqs) { 587 for (i=numqs; i<pool->ltp_numqs; i++) 588 pool->ltp_wqs[i]->ltp_max_count = 0; 589 } else if (numqs > pool->ltp_numqs) { 590 struct ldap_int_thread_poolq_s **wqs; 591 wqs = LDAP_REALLOC(pool->ltp_wqs, numqs * sizeof(struct ldap_int_thread_poolq_s *)); 592 if (wqs == NULL) 593 return(-1); 594 pool->ltp_wqs = wqs; 595 for (i=pool->ltp_numqs; i<numqs; i++) { 596 char *ptr = LDAP_CALLOC(1, sizeof(struct ldap_int_thread_poolq_s) + CACHELINE-1); 597 if (ptr == NULL) { 598 for (; i<numqs; i++) 599 pool->ltp_wqs[i] = NULL; 600 return(-1); 601 } 602 pq = (struct ldap_int_thread_poolq_s *)(((size_t)ptr + CACHELINE-1) & ~(CACHELINE-1)); 603 pq->ltp_free = ptr; 604 pool->ltp_wqs[i] = pq; 605 pq->ltp_pool = pool; 606 rc = ldap_pvt_thread_mutex_init(&pq->ltp_mutex); 607 if (rc != 0) 608 return(rc); 609 rc = ldap_pvt_thread_cond_init(&pq->ltp_cond); 610 if (rc != 0) 611 return(rc); 612 LDAP_STAILQ_INIT(&pq->ltp_pending_list); 613 pq->ltp_work_list = &pq->ltp_pending_list; 614 LDAP_SLIST_INIT(&pq->ltp_free_list); 615 } 616 } 617 rem_thr = pool->ltp_max_count % numqs; 618 rem_pend = pool->ltp_max_pending % numqs; 619 for ( i=0; i<numqs; i++ ) { 620 pq = pool->ltp_wqs[i]; 621 pq->ltp_max_count = pool->ltp_max_count / numqs; 622 if ( rem_thr ) { 623 pq->ltp_max_count++; 624 rem_thr--; 625 } 626 pq->ltp_max_pending = pool->ltp_max_pending / numqs; 627 if ( rem_pend ) { 628 pq->ltp_max_pending++; 629 rem_pend--; 630 } 631 } 632 pool->ltp_numqs = numqs; 633 return 0; 634} 635 636/* Set max #threads. value <= 0 means max supported #threads (LDAP_MAXTHR) */ 637int 638ldap_pvt_thread_pool_maxthreads( 639 ldap_pvt_thread_pool_t *tpool, 640 int max_threads ) 641{ 642 struct ldap_int_thread_pool_s *pool; 643 struct ldap_int_thread_poolq_s *pq; 644 int remthr, i; 645 646 if (! (0 <= max_threads && max_threads <= LDAP_MAXTHR)) 647 max_threads = 0; 648 649 if (tpool == NULL) 650 return(-1); 651 652 pool = *tpool; 653 654 if (pool == NULL) 655 return(-1); 656 657 pool->ltp_conf_max_count = max_threads; 658 if ( !max_threads ) 659 max_threads = LDAP_MAXTHR; 660 pool->ltp_max_count = max_threads; 661 662 remthr = max_threads % pool->ltp_numqs; 663 max_threads /= pool->ltp_numqs; 664 665 for (i=0; i<pool->ltp_numqs; i++) { 666 pq = pool->ltp_wqs[i]; 667 pq->ltp_max_count = max_threads; 668 if (remthr) { 669 pq->ltp_max_count++; 670 remthr--; 671 } 672 } 673 return(0); 674} 675 676/* Inspect the pool */ 677int 678ldap_pvt_thread_pool_query( 679 ldap_pvt_thread_pool_t *tpool, 680 ldap_pvt_thread_pool_param_t param, 681 void *value ) 682{ 683 struct ldap_int_thread_pool_s *pool; 684 int count = -1; 685 686 if ( tpool == NULL || value == NULL ) { 687 return -1; 688 } 689 690 pool = *tpool; 691 692 if ( pool == NULL ) { 693 return 0; 694 } 695 696 switch ( param ) { 697 case LDAP_PVT_THREAD_POOL_PARAM_MAX: 698 count = pool->ltp_conf_max_count; 699 break; 700 701 case LDAP_PVT_THREAD_POOL_PARAM_MAX_PENDING: 702 count = pool->ltp_max_pending; 703 if (count < 0) 704 count = -count; 705 if (count == MAX_PENDING) 706 count = 0; 707 break; 708 709 case LDAP_PVT_THREAD_POOL_PARAM_PAUSING: 710 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 711 count = (pool->ltp_pause != 0); 712 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 713 break; 714 715 case LDAP_PVT_THREAD_POOL_PARAM_OPEN: 716 case LDAP_PVT_THREAD_POOL_PARAM_STARTING: 717 case LDAP_PVT_THREAD_POOL_PARAM_ACTIVE: 718 case LDAP_PVT_THREAD_POOL_PARAM_PENDING: 719 case LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD: 720 { 721 int i; 722 count = 0; 723 for (i=0; i<pool->ltp_numqs; i++) { 724 struct ldap_int_thread_poolq_s *pq = pool->ltp_wqs[i]; 725 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 726 switch(param) { 727 case LDAP_PVT_THREAD_POOL_PARAM_OPEN: 728 count += pq->ltp_open_count; 729 break; 730 case LDAP_PVT_THREAD_POOL_PARAM_STARTING: 731 count += pq->ltp_starting; 732 break; 733 case LDAP_PVT_THREAD_POOL_PARAM_ACTIVE: 734 count += pq->ltp_active_count; 735 break; 736 case LDAP_PVT_THREAD_POOL_PARAM_PENDING: 737 count += pq->ltp_pending_count; 738 break; 739 case LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD: 740 count += pq->ltp_pending_count + pq->ltp_active_count; 741 break; 742 default: 743 break; 744 } 745 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 746 } 747 if (count < 0) 748 count = -count; 749 } 750 break; 751 752 case LDAP_PVT_THREAD_POOL_PARAM_ACTIVE_MAX: 753 break; 754 755 case LDAP_PVT_THREAD_POOL_PARAM_PENDING_MAX: 756 break; 757 758 case LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD_MAX: 759 break; 760 761 case LDAP_PVT_THREAD_POOL_PARAM_STATE: 762 if (pool->ltp_pause) 763 *((char **)value) = "pausing"; 764 else if (!pool->ltp_finishing) 765 *((char **)value) = "running"; 766 else { 767 int i; 768 for (i=0; i<pool->ltp_numqs; i++) 769 if (pool->ltp_wqs[i]->ltp_pending_count) break; 770 if (i<pool->ltp_numqs) 771 *((char **)value) = "finishing"; 772 else 773 *((char **)value) = "stopping"; 774 } 775 break; 776 777 case LDAP_PVT_THREAD_POOL_PARAM_UNKNOWN: 778 break; 779 } 780 781 if ( count > -1 ) { 782 *((int *)value) = count; 783 } 784 785 return ( count == -1 ? -1 : 0 ); 786} 787 788/* 789 * true if pool is pausing; does not lock any mutex to check. 790 * 0 if not pause, 1 if pause, -1 if error or no pool. 791 */ 792int 793ldap_pvt_thread_pool_pausing( ldap_pvt_thread_pool_t *tpool ) 794{ 795 int rc = -1; 796 struct ldap_int_thread_pool_s *pool; 797 798 if ( tpool != NULL && (pool = *tpool) != NULL ) { 799 rc = (pool->ltp_pause != 0); 800 } 801 802 return rc; 803} 804 805/* 806 * wrapper for ldap_pvt_thread_pool_query(), left around 807 * for backwards compatibility 808 */ 809int 810ldap_pvt_thread_pool_backload ( ldap_pvt_thread_pool_t *tpool ) 811{ 812 int rc, count; 813 814 rc = ldap_pvt_thread_pool_query( tpool, 815 LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD, (void *)&count ); 816 817 if ( rc == 0 ) { 818 return count; 819 } 820 821 return rc; 822} 823 824 825/* 826 * wrapper for ldap_pvt_thread_pool_close+free(), left around 827 * for backwards compatibility 828 */ 829int 830ldap_pvt_thread_pool_destroy ( ldap_pvt_thread_pool_t *tpool, int run_pending ) 831{ 832 int rc; 833 834 if ( (rc = ldap_pvt_thread_pool_close( tpool, run_pending )) ) { 835 return rc; 836 } 837 838 return ldap_pvt_thread_pool_free( tpool ); 839} 840 841/* Shut down the pool making its threads finish */ 842int 843ldap_pvt_thread_pool_close ( ldap_pvt_thread_pool_t *tpool, int run_pending ) 844{ 845 struct ldap_int_thread_pool_s *pool, *pptr; 846 struct ldap_int_thread_poolq_s *pq; 847 ldap_int_thread_task_t *task; 848 int i; 849 850 if (tpool == NULL) 851 return(-1); 852 853 pool = *tpool; 854 855 if (pool == NULL) return(-1); 856 857 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex); 858 LDAP_STAILQ_FOREACH(pptr, &ldap_int_thread_pool_list, ltp_next) 859 if (pptr == pool) break; 860 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex); 861 862 if (pool != pptr) return(-1); 863 864 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 865 866 pool->ltp_finishing = 1; 867 if (pool->ltp_max_pending > 0) 868 pool->ltp_max_pending = -pool->ltp_max_pending; 869 870 ldap_pvt_thread_cond_broadcast(&pool->ltp_cond); 871 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 872 873 for (i=0; i<pool->ltp_numqs; i++) { 874 pq = pool->ltp_wqs[i]; 875 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 876 if (pq->ltp_max_pending > 0) 877 pq->ltp_max_pending = -pq->ltp_max_pending; 878 if (!run_pending) { 879 while ((task = LDAP_STAILQ_FIRST(&pq->ltp_pending_list)) != NULL) { 880 LDAP_STAILQ_REMOVE_HEAD(&pq->ltp_pending_list, ltt_next.q); 881 LDAP_FREE(task); 882 } 883 pq->ltp_pending_count = 0; 884 } 885 886 while (pq->ltp_open_count) { 887 ldap_pvt_thread_cond_broadcast(&pq->ltp_cond); 888 ldap_pvt_thread_cond_wait(&pq->ltp_cond, &pq->ltp_mutex); 889 } 890 891 while ((task = LDAP_SLIST_FIRST(&pq->ltp_free_list)) != NULL) 892 { 893 LDAP_SLIST_REMOVE_HEAD(&pq->ltp_free_list, ltt_next.l); 894 LDAP_FREE(task); 895 } 896 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 897 } 898 899 return(0); 900} 901 902/* Destroy the pool, everything must have already shut down */ 903int 904ldap_pvt_thread_pool_free ( ldap_pvt_thread_pool_t *tpool ) 905{ 906 struct ldap_int_thread_pool_s *pool, *pptr; 907 struct ldap_int_thread_poolq_s *pq; 908 int i; 909 910 if (tpool == NULL) 911 return(-1); 912 913 pool = *tpool; 914 915 if (pool == NULL) return(-1); 916 917 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex); 918 LDAP_STAILQ_FOREACH(pptr, &ldap_int_thread_pool_list, ltp_next) 919 if (pptr == pool) break; 920 if (pptr == pool) 921 LDAP_STAILQ_REMOVE(&ldap_int_thread_pool_list, pool, 922 ldap_int_thread_pool_s, ltp_next); 923 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex); 924 925 if (pool != pptr) return(-1); 926 927 ldap_pvt_thread_cond_destroy(&pool->ltp_pcond); 928 ldap_pvt_thread_cond_destroy(&pool->ltp_cond); 929 ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex); 930 for (i=0; i<pool->ltp_numqs; i++) { 931 pq = pool->ltp_wqs[i]; 932 933 assert( !pq->ltp_open_count ); 934 assert( LDAP_SLIST_EMPTY(&pq->ltp_free_list) ); 935 ldap_pvt_thread_cond_destroy(&pq->ltp_cond); 936 ldap_pvt_thread_mutex_destroy(&pq->ltp_mutex); 937 if (pq->ltp_free) { 938 LDAP_FREE(pq->ltp_free); 939 } 940 } 941 LDAP_FREE(pool->ltp_wqs); 942 LDAP_FREE(pool); 943 *tpool = NULL; 944 ldap_int_has_thread_pool = 0; 945 return(0); 946} 947 948/* Thread loop. Accept and handle submitted tasks. */ 949static void * 950ldap_int_thread_pool_wrapper ( 951 void *xpool ) 952{ 953 struct ldap_int_thread_poolq_s *pq = xpool; 954 struct ldap_int_thread_pool_s *pool = pq->ltp_pool; 955 ldap_int_thread_task_t *task; 956 ldap_int_tpool_plist_t *work_list; 957 ldap_int_thread_userctx_t ctx, *kctx; 958 unsigned i, keyslot, hash; 959 int pool_lock = 0, freeme = 0; 960 961 assert(pool != NULL); 962 963 for ( i=0; i<MAXKEYS; i++ ) { 964 ctx.ltu_key[i].ltk_key = NULL; 965 } 966 967 ctx.ltu_pq = pq; 968 ctx.ltu_id = ldap_pvt_thread_self(); 969 TID_HASH(ctx.ltu_id, hash); 970 971 ldap_pvt_thread_key_setdata( ldap_tpool_key, &ctx ); 972 973 if (pool->ltp_pause) { 974 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 975 /* thread_keys[] is read-only when paused */ 976 while (pool->ltp_pause) 977 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex); 978 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 979 } 980 981 /* find a key slot to give this thread ID and store a 982 * pointer to our keys there; start at the thread ID 983 * itself (mod LDAP_MAXTHR) and look for an empty slot. 984 */ 985 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex); 986 for (keyslot = hash & (LDAP_MAXTHR-1); 987 (kctx = thread_keys[keyslot].ctx) && kctx != DELETED_THREAD_CTX; 988 keyslot = (keyslot+1) & (LDAP_MAXTHR-1)); 989 thread_keys[keyslot].ctx = &ctx; 990 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex); 991 992 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 993 pq->ltp_starting--; 994 pq->ltp_active_count++; 995 996 for (;;) { 997 work_list = pq->ltp_work_list; /* help the compiler a bit */ 998 task = LDAP_STAILQ_FIRST(work_list); 999 if (task == NULL) { /* paused or no pending tasks */ 1000 if (--(pq->ltp_active_count) < 1) { 1001 if (pool->ltp_pause) { 1002 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 1003 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 1004 pool_lock = 1; 1005 if (--(pool->ltp_active_queues) < 1) { 1006 /* Notify pool_pause it is the sole active thread. */ 1007 ldap_pvt_thread_cond_signal(&pool->ltp_pcond); 1008 } 1009 } 1010 } 1011 1012 do { 1013 if (pool->ltp_finishing || pq->ltp_open_count > pq->ltp_max_count) { 1014 /* Not paused, and either finishing or too many 1015 * threads running (can happen if ltp_max_count 1016 * was reduced). Let this thread die. 1017 */ 1018 goto done; 1019 } 1020 1021 /* We could check an idle timer here, and let the 1022 * thread die if it has been inactive for a while. 1023 * Only die if there are other open threads (i.e., 1024 * always have at least one thread open). 1025 * The check should be like this: 1026 * if (pool->ltp_open_count>1 && pool->ltp_starting==0) 1027 * check timer, wait if ltp_pause, leave thread; 1028 * 1029 * Just use pthread_cond_timedwait() if we want to 1030 * check idle time. 1031 */ 1032 if (pool_lock) { 1033 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex); 1034 if (!pool->ltp_pause) { 1035 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 1036 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 1037 pool_lock = 0; 1038 } 1039 } else 1040 ldap_pvt_thread_cond_wait(&pq->ltp_cond, &pq->ltp_mutex); 1041 1042 work_list = pq->ltp_work_list; 1043 task = LDAP_STAILQ_FIRST(work_list); 1044 } while (task == NULL); 1045 1046 if (pool_lock) { 1047 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 1048 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 1049 pool_lock = 0; 1050 } 1051 pq->ltp_active_count++; 1052 } 1053 1054 LDAP_STAILQ_REMOVE_HEAD(work_list, ltt_next.q); 1055 pq->ltp_pending_count--; 1056 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 1057 1058 task->ltt_start_routine(&ctx, task->ltt_arg); 1059 1060 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 1061 LDAP_SLIST_INSERT_HEAD(&pq->ltp_free_list, task, ltt_next.l); 1062 } 1063 done: 1064 1065 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex); 1066 1067 /* The pool_mutex lock protects ctx->ltu_key from pool_purgekey() 1068 * during this call, since it prevents new pauses. */ 1069 ldap_pvt_thread_pool_context_reset(&ctx); 1070 1071 thread_keys[keyslot].ctx = DELETED_THREAD_CTX; 1072 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex); 1073 1074 pq->ltp_open_count--; 1075 if (pq->ltp_open_count == 0) { 1076 if (pool->ltp_finishing) 1077 /* let pool_destroy know we're all done */ 1078 ldap_pvt_thread_cond_signal(&pq->ltp_cond); 1079 else 1080 freeme = 1; 1081 } 1082 1083 if (pool_lock) 1084 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 1085 else 1086 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 1087 1088 if (freeme) { 1089 ldap_pvt_thread_cond_destroy(&pq->ltp_cond); 1090 ldap_pvt_thread_mutex_destroy(&pq->ltp_mutex); 1091 LDAP_FREE(pq->ltp_free); 1092 pq->ltp_free = NULL; 1093 } 1094 ldap_pvt_thread_exit(NULL); 1095 return(NULL); 1096} 1097 1098/* Arguments > ltp_pause to handle_pause(,PAUSE_ARG()). arg=PAUSE_ARG 1099 * ensures (arg-ltp_pause) sets GO_* at need and keeps DO_PAUSE/GO_*. 1100 */ 1101#define GO_IDLE 8 1102#define GO_UNIDLE 16 1103#define CHECK_PAUSE 32 /* if ltp_pause: GO_IDLE; wait; GO_UNIDLE */ 1104#define DO_PAUSE 64 /* CHECK_PAUSE; pause the pool */ 1105#define PAUSE_ARG(a) \ 1106 ((a) | ((a) & (GO_IDLE|GO_UNIDLE) ? GO_IDLE-1 : CHECK_PAUSE)) 1107 1108static int 1109handle_pause( ldap_pvt_thread_pool_t *tpool, int pause_type ) 1110{ 1111 struct ldap_int_thread_pool_s *pool; 1112 struct ldap_int_thread_poolq_s *pq; 1113 int ret = 0, pause, max_ltp_pause; 1114 1115 if (tpool == NULL) 1116 return(-1); 1117 1118 pool = *tpool; 1119 1120 if (pool == NULL) 1121 return(0); 1122 1123 if (pause_type == CHECK_PAUSE && !pool->ltp_pause) 1124 return(0); 1125 1126 { 1127 ldap_int_thread_userctx_t *ctx = ldap_pvt_thread_pool_context(); 1128 pq = ctx->ltu_pq; 1129 if ( !pq ) 1130 return(-1); 1131 } 1132 1133 /* Let pool_unidle() ignore requests for new pauses */ 1134 max_ltp_pause = pause_type==PAUSE_ARG(GO_UNIDLE) ? WANT_PAUSE : NOT_PAUSED; 1135 1136 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 1137 1138 pause = pool->ltp_pause; /* NOT_PAUSED, WANT_PAUSE or PAUSED */ 1139 1140 /* If ltp_pause and not GO_IDLE|GO_UNIDLE: Set GO_IDLE,GO_UNIDLE */ 1141 pause_type -= pause; 1142 1143 if (pause_type & GO_IDLE) { 1144 int do_pool = 0; 1145 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 1146 pq->ltp_pending_count++; 1147 pq->ltp_active_count--; 1148 if (pause && pq->ltp_active_count < 1) { 1149 do_pool = 1; 1150 } 1151 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 1152 if (do_pool) { 1153 pool->ltp_active_queues--; 1154 if (pool->ltp_active_queues < 1) 1155 /* Tell the task waiting to DO_PAUSE it can proceed */ 1156 ldap_pvt_thread_cond_signal(&pool->ltp_pcond); 1157 } 1158 } 1159 1160 if (pause_type & GO_UNIDLE) { 1161 /* Wait out pause if any, then cancel GO_IDLE */ 1162 if (pause > max_ltp_pause) { 1163 ret = 1; 1164 do { 1165 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex); 1166 } while (pool->ltp_pause > max_ltp_pause); 1167 } 1168 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 1169 pq->ltp_pending_count--; 1170 pq->ltp_active_count++; 1171 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 1172 } 1173 1174 if (pause_type & DO_PAUSE) { 1175 int i, j; 1176 /* Tell everyone else to pause or finish, then await that */ 1177 ret = 0; 1178 assert(!pool->ltp_pause); 1179 pool->ltp_pause = WANT_PAUSE; 1180 pool->ltp_active_queues = 0; 1181 1182 for (i=0; i<pool->ltp_numqs; i++) 1183 if (pool->ltp_wqs[i] == pq) break; 1184 1185 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 1186 /* temporarily remove ourself from active count */ 1187 pq->ltp_active_count--; 1188 1189 j=i; 1190 do { 1191 pq = pool->ltp_wqs[j]; 1192 if (j != i) 1193 ldap_pvt_thread_mutex_lock(&pq->ltp_mutex); 1194 1195 /* Hide pending tasks from ldap_pvt_thread_pool_wrapper() */ 1196 pq->ltp_work_list = &empty_pending_list; 1197 1198 if (pq->ltp_active_count > 0) 1199 pool->ltp_active_queues++; 1200 1201 ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex); 1202 if (pool->ltp_numqs > 1) { 1203 j++; 1204 j %= pool->ltp_numqs; 1205 } 1206 } while (j != i); 1207 1208 /* Wait for this task to become the sole active task */ 1209 while (pool->ltp_active_queues > 0) 1210 ldap_pvt_thread_cond_wait(&pool->ltp_pcond, &pool->ltp_mutex); 1211 1212 /* restore us to active count */ 1213 pool->ltp_wqs[i]->ltp_active_count++; 1214 1215 assert(pool->ltp_pause == WANT_PAUSE); 1216 pool->ltp_pause = PAUSED; 1217 } 1218 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 1219 1220 return(ret); 1221} 1222 1223/* Consider this task idle: It will not block pool_pause() in other tasks. */ 1224void 1225ldap_pvt_thread_pool_idle( ldap_pvt_thread_pool_t *tpool ) 1226{ 1227 handle_pause(tpool, PAUSE_ARG(GO_IDLE)); 1228} 1229 1230/* Cancel pool_idle(). If the pool is paused, wait it out first. */ 1231void 1232ldap_pvt_thread_pool_unidle( ldap_pvt_thread_pool_t *tpool ) 1233{ 1234 handle_pause(tpool, PAUSE_ARG(GO_UNIDLE)); 1235} 1236 1237/* 1238 * If a pause was requested, wait for it. If several threads 1239 * are waiting to pause, let through one or more pauses. 1240 * The calling task must be active, not idle. 1241 * Return 1 if we waited, 0 if not, -1 at parameter error. 1242 */ 1243int 1244ldap_pvt_thread_pool_pausecheck( ldap_pvt_thread_pool_t *tpool ) 1245{ 1246 return handle_pause(tpool, PAUSE_ARG(CHECK_PAUSE)); 1247} 1248 1249/* 1250 * Wait for a pause, from a non-pooled thread. 1251 */ 1252int 1253ldap_pvt_thread_pool_pausecheck_native( ldap_pvt_thread_pool_t *tpool ) 1254{ 1255 struct ldap_int_thread_pool_s *pool; 1256 1257 if (tpool == NULL) 1258 return(-1); 1259 1260 pool = *tpool; 1261 1262 if (pool == NULL) 1263 return(0); 1264 1265 if (!pool->ltp_pause) 1266 return(0); 1267 1268 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 1269 while (pool->ltp_pause) 1270 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex); 1271 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 1272 return 1; 1273} 1274 1275/* 1276 * Pause the pool. The calling task must be active, not idle. 1277 * Return when all other tasks are paused or idle. 1278 */ 1279int 1280ldap_pvt_thread_pool_pause( ldap_pvt_thread_pool_t *tpool ) 1281{ 1282 return handle_pause(tpool, PAUSE_ARG(DO_PAUSE)); 1283} 1284 1285/* End a pause */ 1286int 1287ldap_pvt_thread_pool_resume ( 1288 ldap_pvt_thread_pool_t *tpool ) 1289{ 1290 struct ldap_int_thread_pool_s *pool; 1291 struct ldap_int_thread_poolq_s *pq; 1292 int i; 1293 1294 if (tpool == NULL) 1295 return(-1); 1296 1297 pool = *tpool; 1298 1299 if (pool == NULL) 1300 return(0); 1301 1302 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex); 1303 assert(pool->ltp_pause == PAUSED); 1304 pool->ltp_pause = 0; 1305 for (i=0; i<pool->ltp_numqs; i++) { 1306 pq = pool->ltp_wqs[i]; 1307 pq->ltp_work_list = &pq->ltp_pending_list; 1308 ldap_pvt_thread_cond_broadcast(&pq->ltp_cond); 1309 } 1310 ldap_pvt_thread_cond_broadcast(&pool->ltp_cond); 1311 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex); 1312 return(0); 1313} 1314 1315/* 1316 * Get the key's data and optionally free function in the given context. 1317 */ 1318int ldap_pvt_thread_pool_getkey( 1319 void *xctx, 1320 void *key, 1321 void **data, 1322 ldap_pvt_thread_pool_keyfree_t **kfree ) 1323{ 1324 ldap_int_thread_userctx_t *ctx = xctx; 1325 int i; 1326 1327 if ( !ctx || !key || !data ) return EINVAL; 1328 1329 for ( i=0; i<MAXKEYS && ctx->ltu_key[i].ltk_key; i++ ) { 1330 if ( ctx->ltu_key[i].ltk_key == key ) { 1331 *data = ctx->ltu_key[i].ltk_data; 1332 if ( kfree ) *kfree = ctx->ltu_key[i].ltk_free; 1333 return 0; 1334 } 1335 } 1336 return ENOENT; 1337} 1338 1339static void 1340clear_key_idx( ldap_int_thread_userctx_t *ctx, int i ) 1341{ 1342 for ( ; i < MAXKEYS-1 && ctx->ltu_key[i+1].ltk_key; i++ ) 1343 ctx->ltu_key[i] = ctx->ltu_key[i+1]; 1344 ctx->ltu_key[i].ltk_key = NULL; 1345} 1346 1347/* 1348 * Set or remove data for the key in the given context. 1349 * key can be any unique pointer. 1350 * kfree() is an optional function to free the data (but not the key): 1351 * pool_context_reset() and pool_purgekey() call kfree(key, data), 1352 * but pool_setkey() does not. For pool_setkey() it is the caller's 1353 * responsibility to free any existing data with the same key. 1354 * kfree() must not call functions taking a tpool argument. 1355 */ 1356int ldap_pvt_thread_pool_setkey( 1357 void *xctx, 1358 void *key, 1359 void *data, 1360 ldap_pvt_thread_pool_keyfree_t *kfree, 1361 void **olddatap, 1362 ldap_pvt_thread_pool_keyfree_t **oldkfreep ) 1363{ 1364 ldap_int_thread_userctx_t *ctx = xctx; 1365 int i, found; 1366 1367 if ( !ctx || !key ) return EINVAL; 1368 1369 for ( i=found=0; i<MAXKEYS; i++ ) { 1370 if ( ctx->ltu_key[i].ltk_key == key ) { 1371 found = 1; 1372 break; 1373 } else if ( !ctx->ltu_key[i].ltk_key ) { 1374 break; 1375 } 1376 } 1377 1378 if ( olddatap ) { 1379 if ( found ) { 1380 *olddatap = ctx->ltu_key[i].ltk_data; 1381 } else { 1382 *olddatap = NULL; 1383 } 1384 } 1385 1386 if ( oldkfreep ) { 1387 if ( found ) { 1388 *oldkfreep = ctx->ltu_key[i].ltk_free; 1389 } else { 1390 *oldkfreep = 0; 1391 } 1392 } 1393 1394 if ( data || kfree ) { 1395 if ( i>=MAXKEYS ) 1396 return ENOMEM; 1397 ctx->ltu_key[i].ltk_key = key; 1398 ctx->ltu_key[i].ltk_data = data; 1399 ctx->ltu_key[i].ltk_free = kfree; 1400 } else if ( found ) { 1401 clear_key_idx( ctx, i ); 1402 } 1403 1404 return 0; 1405} 1406 1407/* Free all elements with this key, no matter which thread they're in. 1408 * May only be called while the pool is paused. 1409 */ 1410void ldap_pvt_thread_pool_purgekey( void *key ) 1411{ 1412 int i, j; 1413 ldap_int_thread_userctx_t *ctx; 1414 1415 assert ( key != NULL ); 1416 1417 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex); 1418 for ( i=0; i<LDAP_MAXTHR; i++ ) { 1419 ctx = thread_keys[i].ctx; 1420 if ( ctx && ctx != DELETED_THREAD_CTX ) { 1421 for ( j=0; j<MAXKEYS && ctx->ltu_key[j].ltk_key; j++ ) { 1422 if ( ctx->ltu_key[j].ltk_key == key ) { 1423 if (ctx->ltu_key[j].ltk_free) 1424 ctx->ltu_key[j].ltk_free( ctx->ltu_key[j].ltk_key, 1425 ctx->ltu_key[j].ltk_data ); 1426 clear_key_idx( ctx, j ); 1427 break; 1428 } 1429 } 1430 } 1431 } 1432 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex); 1433} 1434 1435/* 1436 * Find the context of the current thread. 1437 * This is necessary if the caller does not have access to the 1438 * thread context handle (for example, a slapd plugin calling 1439 * slapi_search_internal()). No doubt it is more efficient 1440 * for the application to keep track of the thread context 1441 * handles itself. 1442 */ 1443void *ldap_pvt_thread_pool_context( ) 1444{ 1445 void *ctx = NULL; 1446 1447 ldap_pvt_thread_key_getdata( ldap_tpool_key, &ctx ); 1448 return ctx ? ctx : (void *) &ldap_int_main_thrctx; 1449} 1450 1451/* 1452 * Free the context's keys. 1453 * Must not call functions taking a tpool argument (because this 1454 * thread already holds ltp_mutex when called from pool_wrapper()). 1455 */ 1456void ldap_pvt_thread_pool_context_reset( void *vctx ) 1457{ 1458 ldap_int_thread_userctx_t *ctx = vctx; 1459 int i; 1460 1461 for ( i=MAXKEYS-1; i>=0; i--) { 1462 if ( !ctx->ltu_key[i].ltk_key ) 1463 continue; 1464 if ( ctx->ltu_key[i].ltk_free ) 1465 ctx->ltu_key[i].ltk_free( ctx->ltu_key[i].ltk_key, 1466 ctx->ltu_key[i].ltk_data ); 1467 ctx->ltu_key[i].ltk_key = NULL; 1468 } 1469} 1470 1471ldap_pvt_thread_t ldap_pvt_thread_pool_tid( void *vctx ) 1472{ 1473 ldap_int_thread_userctx_t *ctx = vctx; 1474 1475 return ctx->ltu_id; 1476} 1477#endif /* LDAP_THREAD_HAVE_TPOOL */ 1478 1479#endif /* LDAP_R_COMPILE */ 1480