2 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
4 * Copyright 1998-2011 The OpenLDAP Foundation.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted only as authorized by the OpenLDAP
11 * A copy of this license is available in file LICENSE in the
12 * top-level directory of the distribution or, alternatively, at
13 * <http://www.OpenLDAP.org/license.html>.
20 #include <ac/signal.h>
21 #include <ac/stdarg.h>
22 #include <ac/stdlib.h>
23 #include <ac/string.h>
28 #include "ldap_pvt_thread.h" /* Get the thread interface */
29 #include "ldap_queue.h"
30 #define LDAP_THREAD_POOL_IMPLEMENTATION
31 #include "ldap_thr_debug.h" /* May rename symbols defined below */
33 #ifndef LDAP_THREAD_HAVE_TPOOL
35 /* Thread-specific key with data and optional free function */
36 typedef struct ldap_int_tpool_key_s {
39 ldap_pvt_thread_pool_keyfree_t *ltk_free;
40 } ldap_int_tpool_key_t;
42 /* Max number of thread-specific keys we store per thread.
43 * We don't expect to use many...
47 /* Max number of threads */
48 #define LDAP_MAXTHR 1024 /* must be a power of 2 */
50 /* (Theoretical) max number of pending requests */
51 #define MAX_PENDING (INT_MAX/2) /* INT_MAX - (room to avoid overflow) */
53 /* Context: thread ID and thread-specific key/data pairs */
54 typedef struct ldap_int_thread_userctx_s {
55 ldap_pvt_thread_t ltu_id;
56 ldap_int_tpool_key_t ltu_key[MAXKEYS];
57 } ldap_int_thread_userctx_t;
60 /* Simple {thread ID -> context} hash table; key=ctx->ltu_id.
61 * Protected by ldap_pvt_thread_pool_mutex except during pauses,
62 * when it is read-only (used by pool_purgekey and pool_context).
63 * Protected by tpool->ltp_mutex during pauses.
66 ldap_int_thread_userctx_t *ctx;
67 /* ctx is valid when not NULL or DELETED_THREAD_CTX */
68 # define DELETED_THREAD_CTX (&ldap_int_main_thrctx + 1) /* dummy addr */
69 } thread_keys[LDAP_MAXTHR];
71 #define TID_HASH(tid, hash) do { \
72 unsigned const char *ptr_ = (unsigned const char *)&(tid); \
74 for (i_ = 0, (hash) = ptr_[0]; ++i_ < sizeof(tid);) \
75 (hash) += ((hash) << 5) ^ ptr_[i_]; \
79 /* Task for a thread to perform */
80 typedef struct ldap_int_thread_task_s {
82 LDAP_STAILQ_ENTRY(ldap_int_thread_task_s) q;
83 LDAP_SLIST_ENTRY(ldap_int_thread_task_s) l;
85 ldap_pvt_thread_start_t *ltt_start_routine;
87 } ldap_int_thread_task_t;
89 typedef LDAP_STAILQ_HEAD(tcq, ldap_int_thread_task_s) ldap_int_tpool_plist_t;
91 struct ldap_int_thread_pool_s {
92 LDAP_STAILQ_ENTRY(ldap_int_thread_pool_s) ltp_next;
94 /* protect members below, and protect thread_keys[] during pauses */
95 ldap_pvt_thread_mutex_t ltp_mutex;
97 /* not paused and something to do for pool_<wrapper/pause/destroy>() */
98 ldap_pvt_thread_cond_t ltp_cond;
100 /* ltp_active_count <= 1 && ltp_pause */
101 ldap_pvt_thread_cond_t ltp_pcond;
103 /* ltp_pause == 0 ? <p_pending_list : &empty_pending_list,
104 * maintaned to reduce work for pool_wrapper()
106 ldap_int_tpool_plist_t *ltp_work_list;
108 /* pending tasks, and unused task objects */
109 ldap_int_tpool_plist_t ltp_pending_list;
110 LDAP_SLIST_HEAD(tcl, ldap_int_thread_task_s) ltp_free_list;
112 /* The pool is finishing, waiting for its threads to close.
113 * They close when ltp_pending_list is done. pool_submit()
114 * rejects new tasks. ltp_max_pending = -(its old value).
118 /* Some active task needs to be the sole active task.
119 * Atomic variable so ldap_pvt_thread_pool_pausing() can read it.
120 * Note: Pauses adjust ltp_<open_count/vary_open_count/work_list>,
121 * so pool_<submit/wrapper>() mostly can avoid testing ltp_pause.
123 volatile sig_atomic_t ltp_pause;
125 /* Max number of threads in pool, or 0 for default (LDAP_MAXTHR) */
128 /* Max number of pending + paused requests, negated when ltp_finishing */
131 int ltp_pending_count; /* Pending or paused requests */
132 int ltp_active_count; /* Active, not paused requests */
133 int ltp_open_count; /* Number of threads, negated when ltp_pause */
134 int ltp_starting; /* Currenlty starting threads */
136 /* >0 if paused or we may open a thread, <0 if we should close a thread.
137 * Updated when ltp_<finishing/pause/max_count/open_count> change.
138 * Maintained to reduce the time ltp_mutex must be locked in
139 * ldap_pvt_thread_pool_<submit/wrapper>().
141 int ltp_vary_open_count;
142 # define SET_VARY_OPEN_COUNT(pool) \
143 ((pool)->ltp_vary_open_count = \
144 (pool)->ltp_pause ? 1 : \
145 (pool)->ltp_finishing ? -1 : \
146 ((pool)->ltp_max_count ? (pool)->ltp_max_count : LDAP_MAXTHR) \
147 - (pool)->ltp_open_count)
150 static ldap_int_tpool_plist_t empty_pending_list =
151 LDAP_STAILQ_HEAD_INITIALIZER(empty_pending_list);
153 static int ldap_int_has_thread_pool = 0;
154 static LDAP_STAILQ_HEAD(tpq, ldap_int_thread_pool_s)
155 ldap_int_thread_pool_list =
156 LDAP_STAILQ_HEAD_INITIALIZER(ldap_int_thread_pool_list);
158 static ldap_pvt_thread_mutex_t ldap_pvt_thread_pool_mutex;
160 static void *ldap_int_thread_pool_wrapper( void *pool );
162 static ldap_pvt_thread_key_t ldap_tpool_key;
164 /* Context of the main thread */
165 static ldap_int_thread_userctx_t ldap_int_main_thrctx;
168 ldap_int_thread_pool_startup ( void )
170 ldap_int_main_thrctx.ltu_id = ldap_pvt_thread_self();
171 ldap_pvt_thread_key_create( &ldap_tpool_key );
172 return ldap_pvt_thread_mutex_init(&ldap_pvt_thread_pool_mutex);
176 ldap_int_thread_pool_shutdown ( void )
178 struct ldap_int_thread_pool_s *pool;
180 while ((pool = LDAP_STAILQ_FIRST(&ldap_int_thread_pool_list)) != NULL) {
181 (ldap_pvt_thread_pool_destroy)(&pool, 0); /* ignore thr_debug macro */
183 ldap_pvt_thread_mutex_destroy(&ldap_pvt_thread_pool_mutex);
184 ldap_pvt_thread_key_destroy( ldap_tpool_key );
189 /* Create a thread pool */
191 ldap_pvt_thread_pool_init (
192 ldap_pvt_thread_pool_t *tpool,
196 ldap_pvt_thread_pool_t pool;
199 /* multiple pools are currently not supported (ITS#4943) */
200 assert(!ldap_int_has_thread_pool);
202 if (! (0 <= max_threads && max_threads <= LDAP_MAXTHR))
204 if (! (1 <= max_pending && max_pending <= MAX_PENDING))
205 max_pending = MAX_PENDING;
208 pool = (ldap_pvt_thread_pool_t) LDAP_CALLOC(1,
209 sizeof(struct ldap_int_thread_pool_s));
211 if (pool == NULL) return(-1);
213 rc = ldap_pvt_thread_mutex_init(&pool->ltp_mutex);
216 rc = ldap_pvt_thread_cond_init(&pool->ltp_cond);
219 rc = ldap_pvt_thread_cond_init(&pool->ltp_pcond);
223 ldap_int_has_thread_pool = 1;
225 pool->ltp_max_count = max_threads;
226 SET_VARY_OPEN_COUNT(pool);
227 pool->ltp_max_pending = max_pending;
229 LDAP_STAILQ_INIT(&pool->ltp_pending_list);
230 pool->ltp_work_list = &pool->ltp_pending_list;
231 LDAP_SLIST_INIT(&pool->ltp_free_list);
233 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
234 LDAP_STAILQ_INSERT_TAIL(&ldap_int_thread_pool_list, pool, ltp_next);
235 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
237 /* Start no threads just yet. That can break if the process forks
238 * later, as slapd does in order to daemonize. On at least POSIX,
239 * only the forking thread would survive in the child. Yet fork()
240 * can't unlock/clean up other threads' locks and data structures,
241 * unless pthread_atfork() handlers have been set up to do so.
249 /* Submit a task to be performed by the thread pool */
251 ldap_pvt_thread_pool_submit (
252 ldap_pvt_thread_pool_t *tpool,
253 ldap_pvt_thread_start_t *start_routine, void *arg )
255 struct ldap_int_thread_pool_s *pool;
256 ldap_int_thread_task_t *task;
257 ldap_pvt_thread_t thr;
267 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
269 if (pool->ltp_pending_count >= pool->ltp_max_pending)
272 task = LDAP_SLIST_FIRST(&pool->ltp_free_list);
274 LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltt_next.l);
276 task = (ldap_int_thread_task_t *) LDAP_MALLOC(sizeof(*task));
281 task->ltt_start_routine = start_routine;
284 pool->ltp_pending_count++;
285 LDAP_STAILQ_INSERT_TAIL(&pool->ltp_pending_list, task, ltt_next.q);
287 /* true if ltp_pause != 0 or we should open (create) a thread */
288 if (pool->ltp_vary_open_count > 0 &&
289 pool->ltp_open_count < pool->ltp_active_count+pool->ltp_pending_count)
294 pool->ltp_starting++;
295 pool->ltp_open_count++;
296 SET_VARY_OPEN_COUNT(pool);
298 if (0 != ldap_pvt_thread_create(
299 &thr, 1, ldap_int_thread_pool_wrapper, pool))
301 /* couldn't create thread. back out of
302 * ltp_open_count and check for even worse things.
304 pool->ltp_starting--;
305 pool->ltp_open_count--;
306 SET_VARY_OPEN_COUNT(pool);
308 if (pool->ltp_open_count == 0) {
309 /* no open threads at all?!?
311 ldap_int_thread_task_t *ptr;
313 /* let pool_destroy know there are no more threads */
314 ldap_pvt_thread_cond_signal(&pool->ltp_cond);
316 LDAP_STAILQ_FOREACH(ptr, &pool->ltp_pending_list, ltt_next.q)
317 if (ptr == task) break;
319 /* no open threads, task not handled, so
320 * back out of ltp_pending_count, free the task,
323 pool->ltp_pending_count--;
324 LDAP_STAILQ_REMOVE(&pool->ltp_pending_list, task,
325 ldap_int_thread_task_s, ltt_next.q);
326 LDAP_SLIST_INSERT_HEAD(&pool->ltp_free_list, task,
331 /* there is another open thread, so this
332 * task will be handled eventually.
336 ldap_pvt_thread_cond_signal(&pool->ltp_cond);
339 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
343 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
348 no_task( void *ctx, void *arg )
353 /* Cancel a pending task that was previously submitted.
354 * Return 1 if the task was successfully cancelled, 0 if
355 * not found, -1 for invalid parameters
358 ldap_pvt_thread_pool_retract (
359 ldap_pvt_thread_pool_t *tpool,
360 ldap_pvt_thread_start_t *start_routine, void *arg )
362 struct ldap_int_thread_pool_s *pool;
363 ldap_int_thread_task_t *task;
373 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
374 LDAP_STAILQ_FOREACH(task, &pool->ltp_pending_list, ltt_next.q)
375 if (task->ltt_start_routine == start_routine &&
376 task->ltt_arg == arg) {
377 /* Could LDAP_STAILQ_REMOVE the task, but that
378 * walks ltp_pending_list again to find it.
380 task->ltt_start_routine = no_task;
381 task->ltt_arg = NULL;
384 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
388 /* Set max #threads. value <= 0 means max supported #threads (LDAP_MAXTHR) */
390 ldap_pvt_thread_pool_maxthreads(
391 ldap_pvt_thread_pool_t *tpool,
394 struct ldap_int_thread_pool_s *pool;
396 if (! (0 <= max_threads && max_threads <= LDAP_MAXTHR))
407 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
409 pool->ltp_max_count = max_threads;
410 SET_VARY_OPEN_COUNT(pool);
412 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
416 /* Inspect the pool */
418 ldap_pvt_thread_pool_query(
419 ldap_pvt_thread_pool_t *tpool,
420 ldap_pvt_thread_pool_param_t param,
423 struct ldap_int_thread_pool_s *pool;
426 if ( tpool == NULL || value == NULL ) {
432 if ( pool == NULL ) {
436 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
438 case LDAP_PVT_THREAD_POOL_PARAM_MAX:
439 count = pool->ltp_max_count;
442 case LDAP_PVT_THREAD_POOL_PARAM_MAX_PENDING:
443 count = pool->ltp_max_pending;
446 if (count == MAX_PENDING)
450 case LDAP_PVT_THREAD_POOL_PARAM_OPEN:
451 count = pool->ltp_open_count;
456 case LDAP_PVT_THREAD_POOL_PARAM_STARTING:
457 count = pool->ltp_starting;
460 case LDAP_PVT_THREAD_POOL_PARAM_ACTIVE:
461 count = pool->ltp_active_count;
464 case LDAP_PVT_THREAD_POOL_PARAM_PAUSING:
465 count = pool->ltp_pause;
468 case LDAP_PVT_THREAD_POOL_PARAM_PENDING:
469 count = pool->ltp_pending_count;
472 case LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD:
473 count = pool->ltp_pending_count + pool->ltp_active_count;
476 case LDAP_PVT_THREAD_POOL_PARAM_ACTIVE_MAX:
479 case LDAP_PVT_THREAD_POOL_PARAM_PENDING_MAX:
482 case LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD_MAX:
485 case LDAP_PVT_THREAD_POOL_PARAM_STATE:
487 pool->ltp_pause ? "pausing" :
488 !pool->ltp_finishing ? "running" :
489 pool->ltp_pending_count ? "finishing" : "stopping";
492 case LDAP_PVT_THREAD_POOL_PARAM_UNKNOWN:
495 ldap_pvt_thread_mutex_unlock( &pool->ltp_mutex );
498 *((int *)value) = count;
501 return ( count == -1 ? -1 : 0 );
505 * true if pool is pausing; does not lock any mutex to check.
506 * 0 if not pause, 1 if pause, -1 if error or no pool.
509 ldap_pvt_thread_pool_pausing( ldap_pvt_thread_pool_t *tpool )
512 struct ldap_int_thread_pool_s *pool;
514 if ( tpool != NULL && (pool = *tpool) != NULL ) {
515 rc = pool->ltp_pause;
522 * wrapper for ldap_pvt_thread_pool_query(), left around
523 * for backwards compatibility
526 ldap_pvt_thread_pool_backload ( ldap_pvt_thread_pool_t *tpool )
530 rc = ldap_pvt_thread_pool_query( tpool,
531 LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD, (void *)&count );
540 /* Destroy the pool after making its threads finish */
542 ldap_pvt_thread_pool_destroy ( ldap_pvt_thread_pool_t *tpool, int run_pending )
544 struct ldap_int_thread_pool_s *pool, *pptr;
545 ldap_int_thread_task_t *task;
552 if (pool == NULL) return(-1);
554 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
555 LDAP_STAILQ_FOREACH(pptr, &ldap_int_thread_pool_list, ltp_next)
556 if (pptr == pool) break;
558 LDAP_STAILQ_REMOVE(&ldap_int_thread_pool_list, pool,
559 ldap_int_thread_pool_s, ltp_next);
560 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
562 if (pool != pptr) return(-1);
564 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
566 pool->ltp_finishing = 1;
567 SET_VARY_OPEN_COUNT(pool);
568 if (pool->ltp_max_pending > 0)
569 pool->ltp_max_pending = -pool->ltp_max_pending;
572 while ((task = LDAP_STAILQ_FIRST(&pool->ltp_pending_list)) != NULL) {
573 LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltt_next.q);
576 pool->ltp_pending_count = 0;
579 while (pool->ltp_open_count) {
580 if (!pool->ltp_pause)
581 ldap_pvt_thread_cond_broadcast(&pool->ltp_cond);
582 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
585 while ((task = LDAP_SLIST_FIRST(&pool->ltp_free_list)) != NULL)
587 LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltt_next.l);
591 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
592 ldap_pvt_thread_cond_destroy(&pool->ltp_pcond);
593 ldap_pvt_thread_cond_destroy(&pool->ltp_cond);
594 ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex);
597 ldap_int_has_thread_pool = 0;
601 /* Thread loop. Accept and handle submitted tasks. */
603 ldap_int_thread_pool_wrapper (
606 struct ldap_int_thread_pool_s *pool = xpool;
607 ldap_int_thread_task_t *task;
608 ldap_int_tpool_plist_t *work_list;
609 ldap_int_thread_userctx_t ctx, *kctx;
610 unsigned i, keyslot, hash;
612 assert(pool != NULL);
614 for ( i=0; i<MAXKEYS; i++ ) {
615 ctx.ltu_key[i].ltk_key = NULL;
618 ctx.ltu_id = ldap_pvt_thread_self();
619 TID_HASH(ctx.ltu_id, hash);
621 ldap_pvt_thread_key_setdata( ldap_tpool_key, &ctx );
623 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
625 /* thread_keys[] is read-only when paused */
626 while (pool->ltp_pause)
627 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
629 /* find a key slot to give this thread ID and store a
630 * pointer to our keys there; start at the thread ID
631 * itself (mod LDAP_MAXTHR) and look for an empty slot.
633 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
634 for (keyslot = hash & (LDAP_MAXTHR-1);
635 (kctx = thread_keys[keyslot].ctx) && kctx != DELETED_THREAD_CTX;
636 keyslot = (keyslot+1) & (LDAP_MAXTHR-1));
637 thread_keys[keyslot].ctx = &ctx;
638 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
640 pool->ltp_starting--;
641 pool->ltp_active_count++;
644 work_list = pool->ltp_work_list; /* help the compiler a bit */
645 task = LDAP_STAILQ_FIRST(work_list);
646 if (task == NULL) { /* paused or no pending tasks */
647 if (--(pool->ltp_active_count) < 2) {
648 /* Notify pool_pause it is the sole active thread. */
649 ldap_pvt_thread_cond_signal(&pool->ltp_pcond);
653 if (pool->ltp_vary_open_count < 0) {
654 /* Not paused, and either finishing or too many
655 * threads running (can happen if ltp_max_count
656 * was reduced). Let this thread die.
661 /* We could check an idle timer here, and let the
662 * thread die if it has been inactive for a while.
663 * Only die if there are other open threads (i.e.,
664 * always have at least one thread open).
665 * The check should be like this:
666 * if (pool->ltp_open_count>1 && pool->ltp_starting==0)
667 * check timer, wait if ltp_pause, leave thread;
669 * Just use pthread_cond_timedwait() if we want to
672 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
674 work_list = pool->ltp_work_list;
675 task = LDAP_STAILQ_FIRST(work_list);
676 } while (task == NULL);
678 pool->ltp_active_count++;
681 LDAP_STAILQ_REMOVE_HEAD(work_list, ltt_next.q);
682 pool->ltp_pending_count--;
683 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
685 task->ltt_start_routine(&ctx, task->ltt_arg);
687 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
688 LDAP_SLIST_INSERT_HEAD(&pool->ltp_free_list, task, ltt_next.l);
692 assert(!pool->ltp_pause); /* thread_keys writable, ltp_open_count >= 0 */
694 /* The ltp_mutex lock protects ctx->ltu_key from pool_purgekey()
695 * during this call, since it prevents new pauses. */
696 ldap_pvt_thread_pool_context_reset(&ctx);
698 ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
699 thread_keys[keyslot].ctx = DELETED_THREAD_CTX;
700 ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
702 pool->ltp_open_count--;
703 SET_VARY_OPEN_COUNT(pool);
704 /* let pool_destroy know we're all done */
705 if (pool->ltp_open_count == 0)
706 ldap_pvt_thread_cond_signal(&pool->ltp_cond);
708 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
710 ldap_pvt_thread_exit(NULL);
715 #define CHECK_PAUSE 1
720 handle_pause( ldap_pvt_thread_pool_t *tpool, int pause_type )
722 struct ldap_int_thread_pool_s *pool;
733 if (pause_type == CHECK_PAUSE && !pool->ltp_pause)
736 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
738 switch( pause_type ) {
740 /* Wait for everyone else to pause or finish */
742 /* Let ldap_pvt_thread_pool_submit() through to its ltp_pause test,
743 * and do not finish threads in ldap_pvt_thread_pool_wrapper() */
744 pool->ltp_open_count = -pool->ltp_open_count;
745 SET_VARY_OPEN_COUNT(pool);
746 /* Hide pending tasks from ldap_pvt_thread_pool_wrapper() */
747 pool->ltp_work_list = &empty_pending_list;
749 while (pool->ltp_active_count > 1) {
750 ldap_pvt_thread_cond_wait(&pool->ltp_pcond, &pool->ltp_mutex);
754 pool->ltp_pending_count--;
755 pool->ltp_active_count++;
759 /* If someone else has already requested a pause, we have to wait */
760 if (pool->ltp_pause) {
761 pool->ltp_pending_count++;
762 pool->ltp_active_count--;
763 /* let the other pool_pause() know when it can proceed */
764 if (pool->ltp_active_count < 2)
765 ldap_pvt_thread_cond_signal(&pool->ltp_pcond);
767 ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
768 } while (pool->ltp_pause);
769 pool->ltp_pending_count--;
770 pool->ltp_active_count++;
773 if (pause_type != GO_IDLE)
775 pool->ltp_pending_count++;
776 pool->ltp_active_count--;
780 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
785 ldap_pvt_thread_pool_idle( ldap_pvt_thread_pool_t *tpool )
787 handle_pause( tpool, GO_IDLE );
791 ldap_pvt_thread_pool_unidle( ldap_pvt_thread_pool_t *tpool )
793 handle_pause( tpool, GO_UNIDLE );
797 * If a pause was requested, wait for it. If several threads
798 * are waiting to pause, let through one or more pauses.
799 * Return 1 if we waited, 0 if not, -1 at parameter error.
802 ldap_pvt_thread_pool_pausecheck( ldap_pvt_thread_pool_t *tpool )
804 return handle_pause( tpool, CHECK_PAUSE );
807 /* Pause the pool. Return when all other threads are paused. */
809 ldap_pvt_thread_pool_pause( ldap_pvt_thread_pool_t *tpool )
811 return handle_pause( tpool, DO_PAUSE );
816 ldap_pvt_thread_pool_resume (
817 ldap_pvt_thread_pool_t *tpool )
819 struct ldap_int_thread_pool_s *pool;
829 ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
831 assert(pool->ltp_pause);
833 if (pool->ltp_open_count <= 0) /* true when paused, but be paranoid */
834 pool->ltp_open_count = -pool->ltp_open_count;
835 SET_VARY_OPEN_COUNT(pool);
836 pool->ltp_work_list = &pool->ltp_pending_list;
838 ldap_pvt_thread_cond_broadcast(&pool->ltp_cond);
840 ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
845 * Get the key's data and optionally free function in the given context.
847 int ldap_pvt_thread_pool_getkey(
851 ldap_pvt_thread_pool_keyfree_t **kfree )
853 ldap_int_thread_userctx_t *ctx = xctx;
856 if ( !ctx || !key || !data ) return EINVAL;
858 for ( i=0; i<MAXKEYS && ctx->ltu_key[i].ltk_key; i++ ) {
859 if ( ctx->ltu_key[i].ltk_key == key ) {
860 *data = ctx->ltu_key[i].ltk_data;
861 if ( kfree ) *kfree = ctx->ltu_key[i].ltk_free;
869 clear_key_idx( ldap_int_thread_userctx_t *ctx, int i )
871 for ( ; i < MAXKEYS-1 && ctx->ltu_key[i+1].ltk_key; i++ )
872 ctx->ltu_key[i] = ctx->ltu_key[i+1];
873 ctx->ltu_key[i].ltk_key = NULL;
877 * Set or remove data for the key in the given context.
878 * key can be any unique pointer.
879 * kfree() is an optional function to free the data (but not the key):
880 * pool_context_reset() and pool_purgekey() call kfree(key, data),
881 * but pool_setkey() does not. For pool_setkey() it is the caller's
882 * responsibility to free any existing data with the same key.
883 * kfree() must not call functions taking a tpool argument.
885 int ldap_pvt_thread_pool_setkey(
889 ldap_pvt_thread_pool_keyfree_t *kfree,
891 ldap_pvt_thread_pool_keyfree_t **oldkfreep )
893 ldap_int_thread_userctx_t *ctx = xctx;
896 if ( !ctx || !key ) return EINVAL;
898 for ( i=found=0; i<MAXKEYS; i++ ) {
899 if ( ctx->ltu_key[i].ltk_key == key ) {
902 } else if ( !ctx->ltu_key[i].ltk_key ) {
909 *olddatap = ctx->ltu_key[i].ltk_data;
917 *oldkfreep = ctx->ltu_key[i].ltk_free;
923 if ( data || kfree ) {
926 ctx->ltu_key[i].ltk_key = key;
927 ctx->ltu_key[i].ltk_data = data;
928 ctx->ltu_key[i].ltk_free = kfree;
929 } else if ( found ) {
930 clear_key_idx( ctx, i );
936 /* Free all elements with this key, no matter which thread they're in.
937 * May only be called while the pool is paused.
939 void ldap_pvt_thread_pool_purgekey( void *key )
942 ldap_int_thread_userctx_t *ctx;
944 assert ( key != NULL );
946 for ( i=0; i<LDAP_MAXTHR; i++ ) {
947 ctx = thread_keys[i].ctx;
948 if ( ctx && ctx != DELETED_THREAD_CTX ) {
949 for ( j=0; j<MAXKEYS && ctx->ltu_key[j].ltk_key; j++ ) {
950 if ( ctx->ltu_key[j].ltk_key == key ) {
951 if (ctx->ltu_key[j].ltk_free)
952 ctx->ltu_key[j].ltk_free( ctx->ltu_key[j].ltk_key,
953 ctx->ltu_key[j].ltk_data );
954 clear_key_idx( ctx, j );
963 * Find the context of the current thread.
964 * This is necessary if the caller does not have access to the
965 * thread context handle (for example, a slapd plugin calling
966 * slapi_search_internal()). No doubt it is more efficient
967 * for the application to keep track of the thread context
970 void *ldap_pvt_thread_pool_context( )
974 ldap_pvt_thread_key_getdata( ldap_tpool_key, &ctx );
975 return ctx ? ctx : (void *) &ldap_int_main_thrctx;
979 * Free the context's keys.
980 * Must not call functions taking a tpool argument (because this
981 * thread already holds ltp_mutex when called from pool_wrapper()).
983 void ldap_pvt_thread_pool_context_reset( void *vctx )
985 ldap_int_thread_userctx_t *ctx = vctx;
988 for ( i=MAXKEYS-1; i>=0; i--) {
989 if ( !ctx->ltu_key[i].ltk_key )
991 if ( ctx->ltu_key[i].ltk_free )
992 ctx->ltu_key[i].ltk_free( ctx->ltu_key[i].ltk_key,
993 ctx->ltu_key[i].ltk_data );
994 ctx->ltu_key[i].ltk_key = NULL;
998 ldap_pvt_thread_t ldap_pvt_thread_pool_tid( void *vctx )
1000 ldap_int_thread_userctx_t *ctx = vctx;
1004 #endif /* LDAP_THREAD_HAVE_TPOOL */