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https://git.openldap.org/openldap/openldap.git
synced 2024-12-21 03:10:25 +08:00
ee73fca523
Replace ltp_state with ltp_finishing. Drop state LDAP_INT_THREAD_POOL_STOPPING, flush pending list instead. ltp_max_pending = default value instead of 0, and negative when finishing.
891 lines
23 KiB
C
891 lines
23 KiB
C
/* $OpenLDAP$ */
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/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
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*
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* Copyright 1998-2008 The OpenLDAP Foundation.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted only as authorized by the OpenLDAP
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* Public License.
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*
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* A copy of this license is available in file LICENSE in the
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* top-level directory of the distribution or, alternatively, at
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* <http://www.OpenLDAP.org/license.html>.
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*/
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#include "portable.h"
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#include <stdio.h>
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#include <ac/signal.h>
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#include <ac/stdarg.h>
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#include <ac/stdlib.h>
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#include <ac/string.h>
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#include <ac/time.h>
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#include <ac/errno.h>
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#include "ldap-int.h"
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#include "ldap_pvt_thread.h" /* Get the thread interface */
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#include "ldap_queue.h"
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#define LDAP_THREAD_POOL_IMPLEMENTATION
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#include "ldap_thr_debug.h" /* May rename symbols defined below */
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#ifndef LDAP_THREAD_HAVE_TPOOL
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/* Thread-specific key with data and optional free function */
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typedef struct ldap_int_tpool_key_s {
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void *ltk_key;
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void *ltk_data;
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ldap_pvt_thread_pool_keyfree_t *ltk_free;
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} ldap_int_tpool_key_t;
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/* Max number of thread-specific keys we store per thread.
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* We don't expect to use many...
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*/
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#define MAXKEYS 32
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/* Max number of threads */
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#define LDAP_MAXTHR 1024 /* must be a power of 2 */
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/* (Theoretical) max number of pending requests */
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#define MAX_PENDING (INT_MAX/2) /* INT_MAX - (room to avoid overflow) */
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/* Context: thread ID and thread-specific key/data pairs */
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typedef struct ldap_int_thread_userctx_s {
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ldap_pvt_thread_t ltu_id;
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ldap_int_tpool_key_t ltu_key[MAXKEYS];
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} ldap_int_thread_userctx_t;
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/* Simple {thread ID -> context} hash table; key=ctx->ltu_id.
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* Protected by ldap_pvt_thread_pool_mutex except during pauses,
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* when it is read-only (used by pool_purgekey and pool_context).
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* Protected by tpool->ltp_mutex during pauses.
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*/
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static struct {
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ldap_int_thread_userctx_t *ctx;
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/* ctx is valid when not NULL or DELETED_THREAD_CTX */
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# define DELETED_THREAD_CTX (&ldap_int_main_thrctx + 1) /* dummy addr */
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} thread_keys[LDAP_MAXTHR];
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#define TID_HASH(tid, hash) do { \
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unsigned const char *ptr_ = (unsigned const char *)&(tid); \
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unsigned i_; \
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for (i_ = 0, (hash) = ptr_[0]; ++i_ < sizeof(tid);) \
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(hash) += ((hash) << 5) ^ ptr_[i_]; \
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} while(0)
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/* Task for a thread to perform */
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typedef struct ldap_int_thread_task_s {
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union {
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LDAP_STAILQ_ENTRY(ldap_int_thread_task_s) q;
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LDAP_SLIST_ENTRY(ldap_int_thread_task_s) l;
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} ltt_next;
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ldap_pvt_thread_start_t *ltt_start_routine;
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void *ltt_arg;
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} ldap_int_thread_task_t;
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struct ldap_int_thread_pool_s {
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LDAP_STAILQ_ENTRY(ldap_int_thread_pool_s) ltp_next;
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/* protect members below, and protect thread_keys[] during pauses */
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ldap_pvt_thread_mutex_t ltp_mutex;
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/* not paused and something to do for pool_<wrapper/pause/destroy>() */
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ldap_pvt_thread_cond_t ltp_cond;
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/* ltp_active_count <= 1 && ltp_pause */
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ldap_pvt_thread_cond_t ltp_pcond;
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/* pending tasks, and unused task objects */
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LDAP_STAILQ_HEAD(tcq, ldap_int_thread_task_s) ltp_pending_list;
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LDAP_SLIST_HEAD(tcl, ldap_int_thread_task_s) ltp_free_list;
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/* The pool is finishing, waiting for its threads to close.
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* They close when ltp_pending_list is done. pool_submit()
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* rejects new tasks. ltp_max_pending = -(its old value).
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*/
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int ltp_finishing;
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/* Some active task needs to be the sole active task.
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* Atomic variable so ldap_pvt_thread_pool_pausing() can read it.
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*/
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volatile sig_atomic_t ltp_pause;
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/* Max number of threads in pool, or 0 for default (LDAP_MAXTHR) */
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int ltp_max_count;
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/* Max number of pending + paused requests, negated when ltp_finishing */
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int ltp_max_pending;
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int ltp_pending_count; /* Pending or paused requests */
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int ltp_active_count; /* Active, not paused requests */
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int ltp_open_count; /* Number of threads */
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int ltp_starting; /* Currenlty starting threads */
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};
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static int ldap_int_has_thread_pool = 0;
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static LDAP_STAILQ_HEAD(tpq, ldap_int_thread_pool_s)
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ldap_int_thread_pool_list =
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LDAP_STAILQ_HEAD_INITIALIZER(ldap_int_thread_pool_list);
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static ldap_pvt_thread_mutex_t ldap_pvt_thread_pool_mutex;
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static void *ldap_int_thread_pool_wrapper( void *pool );
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static ldap_pvt_thread_key_t ldap_tpool_key;
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/* Context of the main thread */
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static ldap_int_thread_userctx_t ldap_int_main_thrctx;
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int
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ldap_int_thread_pool_startup ( void )
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{
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ldap_int_main_thrctx.ltu_id = ldap_pvt_thread_self();
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ldap_pvt_thread_key_create( &ldap_tpool_key );
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return ldap_pvt_thread_mutex_init(&ldap_pvt_thread_pool_mutex);
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}
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int
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ldap_int_thread_pool_shutdown ( void )
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{
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struct ldap_int_thread_pool_s *pool;
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while ((pool = LDAP_STAILQ_FIRST(&ldap_int_thread_pool_list)) != NULL) {
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(ldap_pvt_thread_pool_destroy)(&pool, 0); /* ignore thr_debug macro */
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}
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ldap_pvt_thread_mutex_destroy(&ldap_pvt_thread_pool_mutex);
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ldap_pvt_thread_key_destroy( ldap_tpool_key );
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return(0);
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}
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/* Create a thread pool */
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int
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ldap_pvt_thread_pool_init (
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ldap_pvt_thread_pool_t *tpool,
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int max_threads,
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int max_pending )
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{
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ldap_pvt_thread_pool_t pool;
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int rc;
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/* multiple pools are currently not supported (ITS#4943) */
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assert(!ldap_int_has_thread_pool);
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if (! (0 <= max_threads && max_threads <= LDAP_MAXTHR))
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max_threads = 0;
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if (! (1 <= max_pending && max_pending <= MAX_PENDING))
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max_pending = MAX_PENDING;
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*tpool = NULL;
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pool = (ldap_pvt_thread_pool_t) LDAP_CALLOC(1,
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sizeof(struct ldap_int_thread_pool_s));
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if (pool == NULL) return(-1);
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rc = ldap_pvt_thread_mutex_init(&pool->ltp_mutex);
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if (rc != 0)
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return(rc);
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rc = ldap_pvt_thread_cond_init(&pool->ltp_cond);
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if (rc != 0)
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return(rc);
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rc = ldap_pvt_thread_cond_init(&pool->ltp_pcond);
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if (rc != 0)
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return(rc);
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ldap_int_has_thread_pool = 1;
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pool->ltp_max_count = max_threads;
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pool->ltp_max_pending = max_pending;
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LDAP_STAILQ_INIT(&pool->ltp_pending_list);
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LDAP_SLIST_INIT(&pool->ltp_free_list);
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ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
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LDAP_STAILQ_INSERT_TAIL(&ldap_int_thread_pool_list, pool, ltp_next);
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ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
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#if 0
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/* THIS WILL NOT WORK on some systems. If the process
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* forks after starting a thread, there is no guarantee
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* that the thread will survive the fork. For example,
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* slapd forks in order to daemonize, and does so after
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* calling ldap_pvt_thread_pool_init. On some systems,
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* this initial thread does not run in the child process,
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* but ltp_open_count == 1, so two things happen:
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* 1) the first client connection fails, and 2) when
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* slapd is kill'ed, it never terminates since it waits
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* for all worker threads to exit. */
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/* start up one thread, just so there is one. no need to
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* lock the mutex right now, since no threads are running.
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*/
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pool->ltp_open_count++;
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ldap_pvt_thread_t thr;
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rc = ldap_pvt_thread_create( &thr, 1, ldap_int_thread_pool_wrapper, pool );
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if( rc != 0) {
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/* couldn't start one? then don't start any */
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ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
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LDAP_STAILQ_REMOVE(ldap_int_thread_pool_list, pool,
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ldap_int_thread_pool_s, ltp_next);
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ldap_int_has_thread_pool = 0;
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ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
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ldap_pvt_thread_cond_destroy(&pool->ltp_pcond);
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ldap_pvt_thread_cond_destroy(&pool->ltp_cond);
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ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex);
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LDAP_FREE(pool);
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return(-1);
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}
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#endif
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*tpool = pool;
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return(0);
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}
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/* Submit a task to be performed by the thread pool */
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int
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ldap_pvt_thread_pool_submit (
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ldap_pvt_thread_pool_t *tpool,
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ldap_pvt_thread_start_t *start_routine, void *arg )
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{
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struct ldap_int_thread_pool_s *pool;
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ldap_int_thread_task_t *task;
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ldap_pvt_thread_t thr;
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if (tpool == NULL)
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return(-1);
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pool = *tpool;
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if (pool == NULL)
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return(-1);
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ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
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if (pool->ltp_pending_count >= pool->ltp_max_pending)
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goto failed;
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task = LDAP_SLIST_FIRST(&pool->ltp_free_list);
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if (task) {
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LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltt_next.l);
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} else {
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task = (ldap_int_thread_task_t *) LDAP_MALLOC(sizeof(*task));
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if (task == NULL)
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goto failed;
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}
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task->ltt_start_routine = start_routine;
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task->ltt_arg = arg;
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pool->ltp_pending_count++;
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LDAP_STAILQ_INSERT_TAIL(&pool->ltp_pending_list, task, ltt_next.q);
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if (pool->ltp_pause) {
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ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
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return(0);
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}
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ldap_pvt_thread_cond_signal(&pool->ltp_cond);
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if (pool->ltp_open_count < pool->ltp_active_count + pool->ltp_pending_count
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&& (pool->ltp_open_count <
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(pool->ltp_max_count ? pool->ltp_max_count : LDAP_MAXTHR)))
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{
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pool->ltp_open_count++;
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pool->ltp_starting++;
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if (0 != ldap_pvt_thread_create(
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&thr, 1, ldap_int_thread_pool_wrapper, pool))
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{
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/* couldn't create thread. back out of
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* ltp_open_count and check for even worse things.
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*/
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pool->ltp_starting--;
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pool->ltp_open_count--;
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if (pool->ltp_open_count == 0) {
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/* no open threads at all?!?
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*/
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ldap_int_thread_task_t *ptr;
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/* let pool_destroy know there are no more threads */
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ldap_pvt_thread_cond_signal(&pool->ltp_cond);
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LDAP_STAILQ_FOREACH(ptr, &pool->ltp_pending_list, ltt_next.q)
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if (ptr == task) break;
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if (ptr == task) {
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/* no open threads, task not handled, so
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* back out of ltp_pending_count, free the task,
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* report the error.
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*/
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pool->ltp_pending_count--;
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LDAP_STAILQ_REMOVE(&pool->ltp_pending_list, task,
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ldap_int_thread_task_s, ltt_next.q);
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LDAP_SLIST_INSERT_HEAD(&pool->ltp_free_list, task,
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ltt_next.l);
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goto failed;
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}
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}
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/* there is another open thread, so this
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* task will be handled eventually.
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* continue on, we have signalled that
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* the task is waiting.
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*/
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}
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}
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ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
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return(0);
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failed:
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ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
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return(-1);
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}
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/* Set max #threads. value <= 0 means max supported #threads (LDAP_MAXTHR) */
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int
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ldap_pvt_thread_pool_maxthreads(
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ldap_pvt_thread_pool_t *tpool,
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int max_threads )
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{
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struct ldap_int_thread_pool_s *pool;
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if (! (0 <= max_threads && max_threads <= LDAP_MAXTHR))
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max_threads = 0;
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if (tpool == NULL)
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return(-1);
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pool = *tpool;
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if (pool == NULL)
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return(-1);
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ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
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pool->ltp_max_count = max_threads;
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ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
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return(0);
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}
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/* Inspect the pool */
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int
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ldap_pvt_thread_pool_query(
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ldap_pvt_thread_pool_t *tpool,
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ldap_pvt_thread_pool_param_t param,
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void *value )
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{
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struct ldap_int_thread_pool_s *pool;
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int count = -1;
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if ( tpool == NULL || value == NULL ) {
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return -1;
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}
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pool = *tpool;
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if ( pool == NULL ) {
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return 0;
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}
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ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
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switch ( param ) {
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case LDAP_PVT_THREAD_POOL_PARAM_MAX:
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count = pool->ltp_max_count;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_MAX_PENDING:
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count = pool->ltp_max_pending;
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if (count < 0)
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count = -count;
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if (count == MAX_PENDING)
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count = 0;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_OPEN:
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count = pool->ltp_open_count;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_STARTING:
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count = pool->ltp_starting;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_ACTIVE:
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count = pool->ltp_active_count;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_PAUSING:
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count = pool->ltp_pause;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_PENDING:
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count = pool->ltp_pending_count;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD:
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count = pool->ltp_pending_count + pool->ltp_active_count;
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_ACTIVE_MAX:
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_PENDING_MAX:
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD_MAX:
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_STATE:
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*((char **)value) =
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pool->ltp_pause ? "pausing" :
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!pool->ltp_finishing ? "running" :
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pool->ltp_pending_count ? "finishing" : "stopping";
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break;
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case LDAP_PVT_THREAD_POOL_PARAM_UNKNOWN:
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break;
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}
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ldap_pvt_thread_mutex_unlock( &pool->ltp_mutex );
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if ( count > -1 ) {
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*((int *)value) = count;
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}
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return ( count == -1 ? -1 : 0 );
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}
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/*
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* true if pool is pausing; does not lock any mutex to check.
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* 0 if not pause, 1 if pause, -1 if error or no pool.
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*/
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int
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ldap_pvt_thread_pool_pausing( ldap_pvt_thread_pool_t *tpool )
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{
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int rc = -1;
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struct ldap_int_thread_pool_s *pool;
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if ( tpool != NULL && (pool = *tpool) != NULL ) {
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rc = pool->ltp_pause;
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}
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return rc;
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}
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/*
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* wrapper for ldap_pvt_thread_pool_query(), left around
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* for backwards compatibility
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*/
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int
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ldap_pvt_thread_pool_backload ( ldap_pvt_thread_pool_t *tpool )
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{
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int rc, count;
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rc = ldap_pvt_thread_pool_query( tpool,
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LDAP_PVT_THREAD_POOL_PARAM_BACKLOAD, (void *)&count );
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if ( rc == 0 ) {
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return count;
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}
|
|
|
|
return rc;
|
|
}
|
|
|
|
static void
|
|
flush_pending_list( struct ldap_int_thread_pool_s *pool )
|
|
{
|
|
ldap_int_thread_task_t *task;
|
|
|
|
while ((task = LDAP_STAILQ_FIRST(&pool->ltp_pending_list)) != NULL) {
|
|
LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltt_next.q);
|
|
LDAP_FREE(task);
|
|
}
|
|
}
|
|
|
|
/* Destroy the pool after making its threads finish */
|
|
int
|
|
ldap_pvt_thread_pool_destroy ( ldap_pvt_thread_pool_t *tpool, int run_pending )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool, *pptr;
|
|
ldap_int_thread_task_t *task;
|
|
|
|
if (tpool == NULL)
|
|
return(-1);
|
|
|
|
pool = *tpool;
|
|
|
|
if (pool == NULL) return(-1);
|
|
|
|
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
|
|
LDAP_STAILQ_FOREACH(pptr, &ldap_int_thread_pool_list, ltp_next)
|
|
if (pptr == pool) break;
|
|
if (pptr == pool)
|
|
LDAP_STAILQ_REMOVE(&ldap_int_thread_pool_list, pool,
|
|
ldap_int_thread_pool_s, ltp_next);
|
|
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
|
|
|
|
if (pool != pptr) return(-1);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
|
|
pool->ltp_finishing = 1;
|
|
if (pool->ltp_max_pending > 0)
|
|
pool->ltp_max_pending = -pool->ltp_max_pending;
|
|
if (!run_pending)
|
|
flush_pending_list(pool);
|
|
|
|
while (pool->ltp_open_count) {
|
|
if (!pool->ltp_pause)
|
|
ldap_pvt_thread_cond_broadcast(&pool->ltp_cond);
|
|
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
|
|
}
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
flush_pending_list(pool);
|
|
|
|
while ((task = LDAP_SLIST_FIRST(&pool->ltp_free_list)) != NULL)
|
|
{
|
|
LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltt_next.l);
|
|
LDAP_FREE(task);
|
|
}
|
|
|
|
ldap_pvt_thread_cond_destroy(&pool->ltp_pcond);
|
|
ldap_pvt_thread_cond_destroy(&pool->ltp_cond);
|
|
ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex);
|
|
LDAP_FREE(pool);
|
|
*tpool = NULL;
|
|
ldap_int_has_thread_pool = 0;
|
|
return(0);
|
|
}
|
|
|
|
/* Thread loop. Accept and handle submitted tasks. */
|
|
static void *
|
|
ldap_int_thread_pool_wrapper (
|
|
void *xpool )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool = xpool;
|
|
ldap_int_thread_task_t *task;
|
|
ldap_int_thread_userctx_t ctx, *kctx;
|
|
unsigned i, keyslot, hash;
|
|
|
|
assert(pool != NULL);
|
|
|
|
for ( i=0; i<MAXKEYS; i++ ) {
|
|
ctx.ltu_key[i].ltk_key = NULL;
|
|
}
|
|
|
|
ctx.ltu_id = ldap_pvt_thread_self();
|
|
TID_HASH(ctx.ltu_id, hash);
|
|
|
|
ldap_pvt_thread_key_setdata( ldap_tpool_key, &ctx );
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
|
|
/* thread_keys[] is read-only when paused */
|
|
while (pool->ltp_pause)
|
|
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
|
|
|
|
/* find a key slot to give this thread ID and store a
|
|
* pointer to our keys there; start at the thread ID
|
|
* itself (mod LDAP_MAXTHR) and look for an empty slot.
|
|
*/
|
|
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
|
|
for (keyslot = hash & (LDAP_MAXTHR-1);
|
|
(kctx = thread_keys[keyslot].ctx) && kctx != DELETED_THREAD_CTX;
|
|
keyslot = (keyslot+1) & (LDAP_MAXTHR-1));
|
|
thread_keys[keyslot].ctx = &ctx;
|
|
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
|
|
|
|
pool->ltp_starting--;
|
|
|
|
for (;;) {
|
|
while (pool->ltp_pause)
|
|
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
|
|
|
|
task = LDAP_STAILQ_FIRST(&pool->ltp_pending_list);
|
|
if (task == NULL) {
|
|
if (pool->ltp_finishing)
|
|
break;
|
|
|
|
if (pool->ltp_open_count >
|
|
(pool->ltp_max_count ? pool->ltp_max_count : LDAP_MAXTHR))
|
|
{
|
|
/* too many threads running (can happen if the
|
|
* maximum threads value is set during ongoing
|
|
* operation using ldap_pvt_thread_pool_maxthreads)
|
|
* so let this thread die.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/* we could check an idle timer here, and let the
|
|
* thread die if it has been inactive for a while.
|
|
* only die if there are other open threads (i.e.,
|
|
* always have at least one thread open). the check
|
|
* should be like this:
|
|
* if (pool->ltp_open_count > 1 && pool->ltp_starting == 0)
|
|
* check timer, wait if ltp_pause, leave thread (break;)
|
|
*
|
|
* Just use pthread_cond_timedwait if we want to
|
|
* check idle time.
|
|
*/
|
|
|
|
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
|
|
continue;
|
|
}
|
|
|
|
LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltt_next.q);
|
|
pool->ltp_pending_count--;
|
|
pool->ltp_active_count++;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
task->ltt_start_routine(&ctx, task->ltt_arg);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
LDAP_SLIST_INSERT_HEAD(&pool->ltp_free_list, task, ltt_next.l);
|
|
pool->ltp_active_count--;
|
|
/* let pool_pause know when it is the sole active thread */
|
|
if (pool->ltp_active_count < 2)
|
|
ldap_pvt_thread_cond_signal(&pool->ltp_pcond);
|
|
}
|
|
|
|
/* The ltp_mutex lock protects ctx->ltu_key from pool_purgekey()
|
|
* during this call, since it prevents new pauses. */
|
|
ldap_pvt_thread_pool_context_reset(&ctx);
|
|
|
|
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
|
|
thread_keys[keyslot].ctx = DELETED_THREAD_CTX;
|
|
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
|
|
|
|
pool->ltp_open_count--;
|
|
/* let pool_destroy know we're all done */
|
|
if (pool->ltp_open_count < 1)
|
|
ldap_pvt_thread_cond_signal(&pool->ltp_cond);
|
|
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
ldap_pvt_thread_exit(NULL);
|
|
return(NULL);
|
|
}
|
|
|
|
/* Pause the pool. Return when all other threads are paused. */
|
|
int
|
|
ldap_pvt_thread_pool_pause (
|
|
ldap_pvt_thread_pool_t *tpool )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool;
|
|
|
|
if (tpool == NULL)
|
|
return(-1);
|
|
|
|
pool = *tpool;
|
|
|
|
if (pool == NULL)
|
|
return(0);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
|
|
/* If someone else has already requested a pause, we have to wait */
|
|
if (pool->ltp_pause) {
|
|
pool->ltp_pending_count++;
|
|
pool->ltp_active_count--;
|
|
/* let the other pool_pause() know when it can proceed */
|
|
if (pool->ltp_active_count < 2)
|
|
ldap_pvt_thread_cond_signal(&pool->ltp_pcond);
|
|
do {
|
|
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
|
|
} while (pool->ltp_pause);
|
|
pool->ltp_pending_count--;
|
|
pool->ltp_active_count++;
|
|
}
|
|
|
|
/* Wait for everyone else to pause or finish */
|
|
pool->ltp_pause = 1;
|
|
while (pool->ltp_active_count > 1) {
|
|
ldap_pvt_thread_cond_wait(&pool->ltp_pcond, &pool->ltp_mutex);
|
|
}
|
|
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
return(0);
|
|
}
|
|
|
|
/* End a pause */
|
|
int
|
|
ldap_pvt_thread_pool_resume (
|
|
ldap_pvt_thread_pool_t *tpool )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool;
|
|
|
|
if (tpool == NULL)
|
|
return(-1);
|
|
|
|
pool = *tpool;
|
|
|
|
if (pool == NULL)
|
|
return(0);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
pool->ltp_pause = 0;
|
|
if (!pool->ltp_finishing)
|
|
ldap_pvt_thread_cond_broadcast(&pool->ltp_cond);
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
return(0);
|
|
}
|
|
|
|
/*
|
|
* Get the key's data and optionally free function in the given context.
|
|
*/
|
|
int ldap_pvt_thread_pool_getkey(
|
|
void *xctx,
|
|
void *key,
|
|
void **data,
|
|
ldap_pvt_thread_pool_keyfree_t **kfree )
|
|
{
|
|
ldap_int_thread_userctx_t *ctx = xctx;
|
|
int i;
|
|
|
|
if ( !ctx || !key || !data ) return EINVAL;
|
|
|
|
for ( i=0; i<MAXKEYS && ctx->ltu_key[i].ltk_key; i++ ) {
|
|
if ( ctx->ltu_key[i].ltk_key == key ) {
|
|
*data = ctx->ltu_key[i].ltk_data;
|
|
if ( kfree ) *kfree = ctx->ltu_key[i].ltk_free;
|
|
return 0;
|
|
}
|
|
}
|
|
return ENOENT;
|
|
}
|
|
|
|
static void
|
|
clear_key_idx( ldap_int_thread_userctx_t *ctx, int i )
|
|
{
|
|
for ( ; i < MAXKEYS-1 && ctx->ltu_key[i+1].ltk_key; i++ )
|
|
ctx->ltu_key[i] = ctx->ltu_key[i+1];
|
|
ctx->ltu_key[i].ltk_key = NULL;
|
|
}
|
|
|
|
/*
|
|
* Set or remove data for the key in the given context.
|
|
* key can be any unique pointer.
|
|
* kfree() is an optional function to free the data (but not the key):
|
|
* pool_context_reset() and pool_purgekey() call kfree(key, data),
|
|
* but pool_setkey() does not. For pool_setkey() it is the caller's
|
|
* responsibility to free any existing data with the same key.
|
|
* kfree() must not call functions taking a tpool argument.
|
|
*/
|
|
int ldap_pvt_thread_pool_setkey(
|
|
void *xctx,
|
|
void *key,
|
|
void *data,
|
|
ldap_pvt_thread_pool_keyfree_t *kfree,
|
|
void **olddatap,
|
|
ldap_pvt_thread_pool_keyfree_t **oldkfreep )
|
|
{
|
|
ldap_int_thread_userctx_t *ctx = xctx;
|
|
int i, found;
|
|
|
|
if ( !ctx || !key ) return EINVAL;
|
|
|
|
for ( i=found=0; i<MAXKEYS; i++ ) {
|
|
if ( ctx->ltu_key[i].ltk_key == key ) {
|
|
found = 1;
|
|
break;
|
|
} else if ( !ctx->ltu_key[i].ltk_key ) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
if ( olddatap ) {
|
|
if ( found ) {
|
|
*olddatap = ctx->ltu_key[i].ltk_data;
|
|
} else {
|
|
*olddatap = NULL;
|
|
}
|
|
}
|
|
|
|
if ( oldkfreep ) {
|
|
if ( found ) {
|
|
*oldkfreep = ctx->ltu_key[i].ltk_free;
|
|
} else {
|
|
*oldkfreep = 0;
|
|
}
|
|
}
|
|
|
|
if ( data || kfree ) {
|
|
if ( i>=MAXKEYS )
|
|
return ENOMEM;
|
|
ctx->ltu_key[i].ltk_key = key;
|
|
ctx->ltu_key[i].ltk_data = data;
|
|
ctx->ltu_key[i].ltk_free = kfree;
|
|
} else if ( found ) {
|
|
clear_key_idx( ctx, i );
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Free all elements with this key, no matter which thread they're in.
|
|
* May only be called while the pool is paused.
|
|
*/
|
|
void ldap_pvt_thread_pool_purgekey( void *key )
|
|
{
|
|
int i, j;
|
|
ldap_int_thread_userctx_t *ctx;
|
|
|
|
assert ( key != NULL );
|
|
|
|
for ( i=0; i<LDAP_MAXTHR; i++ ) {
|
|
ctx = thread_keys[i].ctx;
|
|
if ( ctx && ctx != DELETED_THREAD_CTX ) {
|
|
for ( j=0; j<MAXKEYS && ctx->ltu_key[j].ltk_key; j++ ) {
|
|
if ( ctx->ltu_key[j].ltk_key == key ) {
|
|
if (ctx->ltu_key[j].ltk_free)
|
|
ctx->ltu_key[j].ltk_free( ctx->ltu_key[j].ltk_key,
|
|
ctx->ltu_key[j].ltk_data );
|
|
clear_key_idx( ctx, j );
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Find the context of the current thread.
|
|
* This is necessary if the caller does not have access to the
|
|
* thread context handle (for example, a slapd plugin calling
|
|
* slapi_search_internal()). No doubt it is more efficient
|
|
* for the application to keep track of the thread context
|
|
* handles itself.
|
|
*/
|
|
void *ldap_pvt_thread_pool_context( )
|
|
{
|
|
void *ctx = NULL;
|
|
|
|
ldap_pvt_thread_key_getdata( ldap_tpool_key, &ctx );
|
|
return ctx ? ctx : &ldap_int_main_thrctx;
|
|
}
|
|
|
|
/*
|
|
* Free the context's keys.
|
|
* Must not call functions taking a tpool argument (because this
|
|
* thread already holds ltp_mutex when called from pool_wrapper()).
|
|
*/
|
|
void ldap_pvt_thread_pool_context_reset( void *vctx )
|
|
{
|
|
ldap_int_thread_userctx_t *ctx = vctx;
|
|
int i;
|
|
|
|
for ( i=MAXKEYS-1; i>=0; i--) {
|
|
if ( !ctx->ltu_key[i].ltk_key )
|
|
continue;
|
|
if ( ctx->ltu_key[i].ltk_free )
|
|
ctx->ltu_key[i].ltk_free( ctx->ltu_key[i].ltk_key,
|
|
ctx->ltu_key[i].ltk_data );
|
|
ctx->ltu_key[i].ltk_key = NULL;
|
|
}
|
|
}
|
|
|
|
ldap_pvt_thread_t ldap_pvt_thread_pool_tid( void *vctx )
|
|
{
|
|
ldap_int_thread_userctx_t *ctx = vctx;
|
|
|
|
return ctx->ltu_id;
|
|
}
|
|
#endif /* LDAP_THREAD_HAVE_TPOOL */
|